Search Results (11,398)

This study investigates the molecular mechanisms underlying fruit cracking in Akebia trifoliata, a phenomenon that significantly impacts fruit quality and marketability. Through comprehensive physiological, biochemical, and transcriptomic analyses, we identified key changes in cell wall components and enzymatic activities during fruit ripening. Our results revealed that ventral suture tissues exhibit significantly elevated activities of polygalacturonase (PG) and β-galactosidase compared to dorsoventral line tissues, indicating their crucial roles in cell wall degradation and structural weakening. The cellulose content in VS tissues peaked early and declined during ripening, while DL tissues maintained relatively stable cellulose levels, highlighting the importance of cellulose dynamics in fruit cracking susceptibility. Transcriptomic analysis revealed differentially expressed genes (DEGs) associated with pectin biosynthesis and catabolism, cell wall organization, and oxidoreductase activities, indicating significant transcriptional regulation. Key genes like AKT032945 (pectinesterase) and AKT045678 (polygalacturonase) were identified as crucial for cell wall loosening and pericarp dehiscence. Additionally, expansin-related genes AKT017642, AKT017643, and AKT021517 were expressed during critical stages, promoting cell wall loosening. Genes involved in auxin-activated signaling and oxidoreductase activities, such as AKT022903 (auxin response factor) and AKT054321 (peroxidase), were also differentially expressed, suggesting roles in regulating cell wall rigidity. Moreover, weighted gene co-expression network analysis (WGCNA) identified key gene modules correlated with traits like pectin lyase activity and soluble pectin content, pinpointing potential targets for genetic manipulation. Our findings offer valuable insights into the molecular basis of fruit cracking in A. trifoliata, laying a foundation for breeding programs aimed at developing crack-resistant varieties to enhance fruit quality and commercial viability. Full article

Salinity poses a significant environmental challenge, limiting plant growth and development. To cultivate salt-tolerant plants, it is crucial to understand the physiological, biochemical, and molecular responses and adaptations to salt stress, as well as to explore natural genetic resources linked to salt tolerance. In this review, we provide a detailed overview of the mechanisms behind morphological and physiological responses triggered by salt stress, including salt damage to plants, the disturbance of cell osmotic potentials and ion homeostasis, lipid peroxidation, and the suppression of photosynthesis and growth. We also describe the physiological mechanisms that confer salt tolerance in plants, such as osmotic adjustments, reactive oxygen species (ROS) scavenging, photosynthetic responses, phytohormone regulation, and ion regulation. Additionally, we summarize the salt-stress sensing and signaling pathways, gene regulatory networks, as well as salt-tolerance mechanisms in plants. The key pathways involved in salt-stress signal perception and transduction, including Ca²⁺-dependent protein kinase (CDPK) cascades, the salt overly sensitive (SOS) pathway, and the abscisic acid (ABA) pathway, are discussed, along with relevant salt-stress-responsive genes and transcription factors. In the end, the important issues and challenges related to salt tolerance for future research are addressed. Overall, this review aims to provide essential insights for the future cultivation and breeding of crops and fruits. Full article

Understanding the intricate relationship between drought stress and corn yield is crucial for ensuring food security and sustainable agriculture in the face of climate change. This study investigates the subtle effects of drought stress on corn physiological, morphological, and spectral characteristics at different growth stages, in order to construct a new drought index to characterize drought characteristics, so as to provide valuable insights for maize recovery mechanism and yield prediction. Specific conclusions are as follows. Firstly, the impact of drought stress on corn growth and development shows a gradient effect, with the most significant effects observed during the elongation stage and tasseling stage. Notably, Soil and Plant Analyzer Development (SPAD) and Leaf Area Index (LAI) are significantly affected during the silking stage, while plant height and stem width remain relatively unaffected. Secondly, spectral feature analysis reveals that, from the elongation stage to the silking stage, canopy reflectance exhibits peak–valley variations. Drought severity correlates positively with reflectance in the visible and shortwave infrared bands and negatively with reflectance in the near-infrared band. Canopy spectra during the silking stage are more affected by moderate and severe drought stress. Thirdly, LAI shows a significant positive correlation with yield, indicating its reliability in explaining yield variations. Finally, the yield-related drought index (YI) constructed based on Convolutional Neural Network (CNN), Random Forest (RF) and Multiple Linear Regression (MLR) methods has a good effect on revealing drought characteristics (R = 0.9332, p < 0.001). This study underscores the importance of understanding corn responses to drought stress at various growth stages for effective yield prediction and agricultural management strategies. Full article

With the intensification of global climate change and environmental stress, research on abiotic and biotic stress resistance in maize is particularly important. High temperatures and drought, low temperatures, heavy metals, salinization, and diseases are widespread stress factors that can reduce maize yields and are a focus of maize-breeding research. Molecular biology provides new opportunities for the study of maize and other plants. This article reviews the physiological and biochemical responses of maize to high temperatures and drought, low temperatures, heavy metals, salinization, and diseases, as well as the molecular mechanisms associated with them. Special attention is given to key transcription factors in signal transduction pathways and their roles in regulating maize stress adaptability. In addition, the application of transcriptomics, genome-wide association studies (GWAS), and QTL technology provides new strategies for the identification of molecular markers and genes for maize-stress-resistance traits. Crop genetic improvements through gene editing technologies such as the CRISPR/Cas system provide a new avenue for the development of new stress-resistant varieties. These studies not only help to understand the molecular basis of maize stress responses but also provide important scientific evidence for improving crop tolerance through molecular biological methods. Full article

Carnosine is a natural dipeptide made up of L-histidine and β-alanine which is rich in muscle tissues and has multiple physiological functions. The current research aimed to investigate the effects of varied carnosine concentrations in low-fishmeal feed on the growth, muscle antioxidant capacity and flesh quality of orange-spotted grouper. Carnosine was supplemented at doses of 0, 10, 20, 40, 80, 160, and 320 mg/kg in low-fishmeal feed. Seven groups with three tanks of fish (11.4 ± 0.1 g/fish) were allotted one of the diets during the 8-week feeding trial. The growth rate, body protein content, muscle activities of superoxide dismutase and catalase, and muscle adhesiveness showed positive linear response and/or an open upward parabola with increasing carnosine concentrations, with a peak at 160 mg/kg of carnosine. Feed utilization, serum total protein content, gut trypsin activity, muscle glutathione peroxidase, total antioxidant capacity, muscle hardness, gumminess, chewiness and resilience followed the same pattern as the growth rate, reaching a peak at 320 mg/kg of carnosine; while the opposite trend was observed, reaching a minimum at 320 mg/kg for muscle malondialdehyde and 160 mg/kg for muscle liquid and water loss. The results indicated that appropriate carnosine addition could improve growth performance, muscle antioxidant capacity and flesh quality of grouper. The suitable inclusion concentration was estimated to be 195.14 mg/kg to achieve the best specific growth rate. Full article

Background/Objectives: The escalating challenge of antimicrobial resistance (AMR) necessitates the development of targeted antibiotic delivery platforms, minimising systemic administration. Polymer-based drug delivery emerges as a promising solution, ensuring sustained release and prolonged efficacy of bioactive compounds, ensuring long-term efficacy. Methods: This study focuses on encapsulating rifampicin (RIF), a key antibiotic for orthopaedic and wound-related infections, within Poly(d,l-lactide-co-glycolide) (PLGA), a biodegradable polymer, through solvent casting, to formulate a PLGA-RIF composite membrane. Comprehensive characterisation, employing Fourier-transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermal analysis and X-ray Diffraction (XRD), confirmed the integrity of both the starting and produced materials. UV-Vis spectroscopy revealed a controlled drug release profile over 21 days in various media, with the chosen media influencing the drug release, notably the tryptic soya broth (TSB) caused the highest release. The quantitative assessment of the antimicrobial efficacy of the developed PLGA-RIF composite was conducted by measuring the size of the inhibition zones against both Gram-negative and Gram-positive bacteria. Results: The results confirmed the composite’s potential as a robust antibacterial biomaterial, demonstrating a rapid and effective antibacterial response. Cytocompatibility tests incorporated human fibroblast and osteoblast-like cell lines and demonstrated that the RIF:PLGA (1:8) formulation maintained eukaryotic cell viability, indicating the composite’s potential for targeted medical applications in combating bacterial infections with minimal systemic impact. Conclusions: This study presents the significance of investigating drug release within appropriate and relevant physiological media. A key novelty of this work therefore lies in the exploration of drug release dynamics across different media, allowing for a comprehensive understanding of how varying physiological conditions may influence drug release and its effect on biological responses. Full article

Larch is a cold-temperate tree species native to the northern hemisphere and tolerant to low temperatures. It is one of the most significant timber species in Northeast China. This study examined growth changes in hybrid larch seedlings from five lines to explore the physiological responses of these seedlings to low-temperature stress. Using 8-month-old hybrids of larch seedlings, we subjected the plants to cold stress at 4 °C and freezing stress at −20 °C over three periods of 6, 12, and 24 h, and treatment at 25 °C was used as a control. Results showed that significant correlations were found among the growth indicators, with larch line 1306 having the lowest incremental growth indicators, the largest root-to-crown ratio, and better cold tolerance than the other larch lines. The levels of soluble sugars (SSs), soluble proteins (SPs), malondialdehyde (MDA), and relative electrolyte leakage (REC) increased significantly in all lines under low-temperature stress. The activities of superoxide dismutase (SOD) and catalase (CAT) showed variation over time. Significant correlations were found between MDA and REL, SS, SR, Pro, CAT, and SOD in most of the lines; no significant correlation was found between MDA and the other indices in lines 1301 and 1309; and significant correlations were found between most of the physiological indices in line 1306. Full article

The central nervous system (CNS) relies on precise regulation of potassium ion (K⁺) concentrations to maintain physiology. This regulation involves complex cellular and molecular mechanisms that work in concert to regulate both intracellular and extracellular K⁺ levels. Inflammation, a key physiological response, encompasses a series of cell-specific events leading to inflammasome activation. Perturbations in K⁺-sensitive processes can result in either chronic or uncontrolled inflammation, highlighting the intricate relationship between K⁺ homeostasis and inflammatory signalling. This review explores molecular targets that influence K⁺ homeostasis and have been implicated in inflammatory cascades, offering potential therapeutic avenues for managing inflammation. We examine both cell-specific and common molecular targets across different cell types, providing a comprehensive overview of the interplay between K⁺ regulation and inflammation in the CNS. By elucidating these mechanisms, we identify leads for drug discovery programmes aimed at modulating inflammatory responses. Additionally, we highlight potential consequences of targeting individual molecular entities for therapeutic purposes, emphasizing the need for a nuanced approach in developing anti-inflammatory strategies. This review considers current knowledge on K⁺-sensitive inflammatory processes within the CNS, offering critical insights into the molecular underpinnings of inflammation and potential therapeutic interventions. Our findings underscore the importance of considering K⁺ homeostasis in the development of targeted therapies for inflammatory conditions within the CNS. Full article

Increasingly, humans are exposed to different activities at work, at home, and in general in their daily lives that generate episodes of stress. In many cases, these episodes could produce disorders in their health and reduce their quality of life. For this reason, it is crucial to implement mechanisms that can detect stress in individuals and develop applications that provide feedback through various activities to help reduce stress levels. Physiological parameters, such as galvanic skin response (GSR) and heart rate (HR) are indicative of stress-related changes. There exist methodologies that use wearable sensors to measure these stress levels. In this study, a sensor of blood volume pulse (BVP) and an electrocardiography (ECG) sensor were utilized to obtain metrics like heart rate variability (HRV) and pulse arrival time (PAT). Their features were extracted, processed, and analyzed for anxiety detection. The classification performance was evaluated using decision trees, a support vector machine (SVM), and meta-classifiers to accurately distinguish between “stressed” and “non-stressed” states. We obtained the best results with the SVM classifier using all the features. Additionally, we found that the ECG AD8232 sensor provided more reliable data compared to the photoplethysmography (PPG) signal obtained from the MAX30100 sensor. Therefore, the ECG is a more accurate tool for assessing emotional states related to stress and anxiety. Full article

Recent findings indicate that human microbiota can excrete trace amines, dopamine, and serotonin. These neurotransmitters (NTs) can either affect classical neurotransmitter signaling or directly trigger trace amine-associated receptors (TAARs), with still unclear consequences for host physiology. Compared to gut microbiota, less information is available on the role of skin microbiota in NT production. To explore this, 1909 skin isolates, mainly from the genera Staphylococcus, Bacillus, and Corynebacterium, were tested for NT production. Only 6.7% of the isolates were capable of producing NTs, all of which belonged to the Staphylococcus genus. Based on substrate specificity, we identified two distinct profiles among the NT producers. One group primarily produced tryptamine (TRY) and phenylethylamine (PEA), while the other mainly produced tyramine (TYM) and dopamine (Dopa). These differing production profiles could be attributed to the activity of two distinct aromatic amino acid decarboxylase enzymes, SadA and TDC, responsible for generating the TRY/PEA and TYM/Dopa product spectra, respectively. SadA and TDC orthologues differ in structure and size; SadA has approximately 475 amino acids, whereas the TDC type consists of about 620 amino acids. The genomic localization of the respective genes also varies: tdc genes are typically found in small, conserved gene clusters, while sadA genes are not. The heterologous expression of sadA and tdc in Escherichia coli yielded the same product spectrum as the parent strains. The possible effects of skin microbiota-derived NTs on neuroreceptor signaling in the human host remain to be investigated. Full article

Smart sensors represent a significant advancement in modern sports science, and their effective use enhances the ability to monitor and analyze athlete performance in real time. The integration of these sensors has enhanced the accuracy of data collection related to physical activity, biomechanics, and physiological responses, thus providing valuable insights for performance optimization, injury prevention, and rehabilitation. This paper provides an overview of the research progress in the application of smart sensors in the field of sports science; highlights the current advances, challenges, and future directions in the deployment of smart sensor technologies; and anticipates their transformative impact on sports science and athlete development. Full article

The classical function of the mineralocorticoid receptor (MR) is to maintain electrolytic homeostasis and control extracellular volume and blood pressure. The MR is expressed in the central nervous system (CNS) and is involved in the regulation of the hypothalamic–pituitary–adrenal (HPA) axis as well as sleep physiology, playing a role in the non-rapid eye movement (NREM) phase of sleep. Some patients with psychiatric disorders have very poor sleep quality, and a relationship between MR dysregulation and this disorder has been found in them. In addition, the MR is involved in the regulation of the renal peripheral clock. One of the most common comorbidities observed in patients with chronic kidney disease (CKD) is poor sleep quality. Patients with CKD experience sleep disturbances, including reduced sleep duration, sleep fragmentation, and insomnia. To date, no studies have specifically investigated the relationship between MR activation and CKD-associated sleep disturbances. However, in this review, we analyzed the environment that occurs in CKD and proposed two MR-related mechanisms that may be responsible for these sleep disturbances: the circadian clock disruption and the high levels of MR agonist observed in CKD. Full article

Pigeon pea (Cajanus cajan (L.) Millsp.), a potential legume as an economic source of protein, is commonly cultivated in tropical and subtropical regions of the world. It possesses medicinal properties and acts as a cash crop, benefiting low-income farmers economically. The identification of pigeon peas exhibiting drought tolerance has become crucial in addressing water scarcity issues in the agriculture sector. In addition, exploring the genetic diversity among genotypes is important for conservation, management of genetic resources, and breeding programs. The aim of this study was to evaluate the morpho-physiological and biochemical responses of selected pigeon pea genotypes under pot-induced water stress conditions through different field capacities as well as the genetic diversity using start codon targeted (SCoT) markers. A significant variation was observed for the physiological traits studied. The accumulation of fresh weight (FW) and dry weight (DW) was significantly reduced in moderate and severe drought stress conditions. The lowest % DW decrease was found in LM (35.39%), KAT (39.43%), and SM (46.98%) than other genotypes at severe drought stress. Analyses of physiological responses including the photosynthetic efficiency (Phi2), the chlorophyll content (SPAD), and the relative water content (RWC) revealed positive and negative correlations with various parameters, reflecting the impact of drought stress on the chlorophyll content. The results revealed that biochemical traits including the total phenolic content, soluble sugars, proline, total protein, total amino acids, and free amino acids were variably and significantly increased under water stress. Antioxidant enzyme activity levels, specifically ascorbate peroxidase (APX) and catalase, varied among the genotypes and in response to severe water stress, offering further insights into adaptive responses. The eight genotypes analysed by use of 20 SCoT markers revealed 206 alleles and an average of 10.3 alleles per locus. Genetic similarity ranged from 0.336 to 0.676, clustering the pigeon pea genotypes into two major groups by the unweighted pair group method of arithmetic averages (UPGMA) cluster analysis. Principal coordinate analysis (PCoA) explained 43.11% of genetic variation and based on analysis of molecular variance, a high genetic variation (80%) within populations was observed, emphasizing the potential for genetic improvement. Among the eight genotypes studied, LM and KAT were drought tolerant and genetically diverse and therefore could be used as parents for developing drought tolerance in pigeon pea. Full article

Indoleamine 2,3-dioxygenase 1 (IDO1) and IDO2 originated from gene duplication before vertebrate divergence. While IDO1 has a well-defined role in immune regulation, the biological role of IDO2 remains unclear. Discovered in 2007, IDO2 is located near the IDO1 gene. Because of their high sequence similarity, IDO2 was initially thought to be a tryptophan (Trp)-degrading enzyme like IDO1. Differently from what expected, IDO2 displays extremely low catalytic activity toward Trp. Nevertheless, many studies, often contradictory, have tried to demonstrate that IDO2 modulates immune responses by catabolizing Trp into kynurenine, an unconvincing hypothesis linked to an incomplete understanding of IDO2’s activity. In this study, we review IDO2’s functional role beyond Trp metabolism. IDO2’s evolutionary persistence across species, despite being almost inactive as an enzyme, suggests it has some relevant biological importance. IDO2 expression in human normal cells is poor, but significant in various cancers, with two prevalent SNPs. Overall, the comparison of IDO2 to IDO1 as a Trp-degrading enzyme may have led to misunderstandings about IDO2’s true physiological and pathological roles. New insights suggest that IDO2 might function more as a signaling molecule, particularly in cancer contexts, and further studies could reveal its potential as a target for cancer therapy. Full article

Biostimulants include a wide array of microorganisms and substances that can exert beneficial effects on plant development and growth, often enhancing nutrient uptake and improving tolerance against abiotic and biotic stress. Depending on their composition and time of application, these products can influence plant physiology directly as growth regulators or indirectly through environmental condition changes in the rhizosphere, such as nutrient and water availability. This review evaluated 48 case studies from 39 papers to summarize the effects of biostimulant application on fruit and tuber yields and on the quality of processing tomato and potato in open field conditions. For potato, PGPR bacteria were the main studied biostimulant, whereas the low number of studies on processing tomato did not permit us to delineate a trend. The yield and quality were greatly influenced by cultivars and biostimulant composition, application method, period, and dose. For processing tomato, a positive effect of the biostimulant application on the marketable yield was reported in 79% of the case studies, whereas for potato, the effect was reported in only 47%. Few studies, on processing tomato and potato, also reported data for quality parameters with contrasting results. The variability of crop response to biostimulant application in open field conditions highlights the need for more comprehensive studies. Such studies should focus on diverse cultivars, deeply understand the interaction of biostimulant application with agronomic management (e.g., irrigation and fertilization), and evaluate yield and quality parameters. This approach is crucial to fully understand the potential and limitations of biostimulant applications in agriculture, particularly regarding their role in sustainable crop production. Full article