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This article represents a republication of an article originally published in STH in 2005. This republication is to help celebrate 50 years of publishing for STH. The original abstract follows. Platelets are specialized blood cells that play central roles in physiologic and pathologic processes of hemostasis, inflammation, tumor metastasis, wound healing, and host defense. Activation of platelets is crucial for platelet function that includes a complex interplay of adhesion and signaling molecules. This article gives an overview of the activation processes involved in primary and secondary hemostasis, for example, platelet adhesion, platelet secretion, platelet aggregation, microvesicle formation, and clot retraction/stabilization. In addition, activated platelets are predominantly involved in cross-talk to other blood and vascular cells. Stimulated "sticky" platelets enable recruitment of leukocytes at sites of vascular injury under high shear conditions. Platelet-derived microparticles as well as soluble adhesion molecules, sP-selectin and sCD40L, shed from the surface of activated platelets, are capable of activating, in turn, leukocytes and endothelial cells. This article focuses further on the new view of receptor-mediated thrombin generation of human platelets, necessary for the formation of a stable platelet–fibrin clot during secondary hemostasis. Finally, special emphasis is placed on important stimulatory and inhibitory signaling pathways that modulate platelet function. [ABSTRACT FROM AUTHOR]

Background: Seed aging, a natural and inevitable process occurring during storage. Oats, an annual herb belonging to the Gramineae family and pooideae. In addition to being a healthy food, oats serve as ecological pastures, combating soil salinization and desertification. They also play a role in promoting grassland agriculture and supplementing winter livestock feed. However, the high lipid and fat derivatives contents of oat seeds make them susceptible to deterioration, as fat derivatives are prone to rancidity, affecting oat seed production, storage, development, and germplasm resource utilization. Comparative studies on the effects of aging on physiology and cytological structure in covered and naked oat seeds are limited. Thus, our study aimed to determine the mechanism underlying seed deterioration in artificially aged 'LongYan No. 3' (A. sativa) and 'BaiYan No. 2' (A. nuda) seeds, providing a basis for the physiological evaluation of oat seed aging and serving as a reference for scientifically safe storage and efficient utilization of oats. Results: In both oat varieties, superoxide dismutase and catalase activities in seeds showed increasing and decreasing trends, respectively. Variance analysis revealed significant differences and interaction in all measured indicators of oat seeds between the two varieties at different aging times. 'LongYan No. 3' seeds, aged for 24–96 h, exhibited a germination rate of < 30%, Conductivity, malondialdehyde, soluble sugar, and soluble protein levels increased more significantly than the 'BaiYan No. 2'. With prolonged aging leading to cell membrane degradation, reactive oxygen species accumulation, disrupted antioxidant enzyme system, evident embryo cell swelling, and disordered cell arrangement, blocking the nutrient supply route. Simultaneously, severely concentrated chromatin in the nucleus, damaged mitochondrial structure, and impaired energy metabolism were noted, resulting in the loss of 'LongYan No. 3' seed vitality and value. Conversely, 'BaiYan No. 2' seeds showed a germination rate of 73.33% after 96 h of aging, consistently higher antioxidant enzyme activity during aging, normal embryonic cell shape, and existence of the endoplasmic reticulum. Conclusions: ROS accumulation and antioxidant enzyme system damage in aged oat seeds, nuclear chromatin condensation, mitochondrial structure damage, nucleic acid metabolism and respiration weakened, oat seed vigor decreased. 'LongYan No. 3' seeds were more severely damaged under artificial aging than 'BaiYan No. 2' seeds, highlighting their heightened susceptibility to aging effects. [ABSTRACT FROM AUTHOR]

The anaerobic capacity (AC[La]+EPOCfast) method is of interest as it can differentiate between the contributions of phosphocreatine (PCr) and glycolytic energy, assess the anaerobic metabolism during a single effort, and evaluate various exercise modalities. However, no previous studies have investigated whether the superiority of the PCr and glycolytic systems can be assessed in athletes with high anaerobic capacity. This study aimed to compare the AC[La]+EPOCfast method in seven sprinters (SP) and seven middle-distance runners (MD). The participants underwent a graded exercise test and constant-load exercise at 115% ˙VO2max until exhaustion using a bicycle ergometer. AC[La]+EPOCfast was calculated as the sum of oxygen equivalents from the phosphagen (EPCr) and glycolytic (ELa) pathways. This study reveals that there was no significant difference in AC[La]+EPOCfast or maximal accumulated oxygen deficit (MAOD) between the two groups. Although EPCr was not significantly different between groups, ELa was significantly higher in the SP group than in the MD group. In conclusion, the AC[La]+EPOCfast method can be used to evaluate high and low anaerobic capacities. However, further studies on athletes with high aerobic capacity are required. [ABSTRACT FROM AUTHOR]

This study investigated the interactive effects of drought stress with biochar on plant growth, the physiological and biochemical attributes of soybean seedlings. A pot trial tested the effect of amending a loamy sandy soil with biochar at three doses: 0%, 3% and 6% in the alleviation of drought stress, imposed by adjusting soil moisture content at three levels (in terms of soil field capacity, FC): 100% FC, 75% FC and 50% FC. Water deficit negatively influenced the growth of soybean seedlings and chlorophyll content of leaves, particularly in non-amended plants whereas biochar amendment boosted the growth and chlorophyll content, particularly under drought stress. Drought stress elevated malondialdehyde (MDA), hydrogen peroxide (H2O2), proline, sucrose and abscisic acid (ABA) contents as well as the antioxidant enzyme activity [peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD)] of soybean leaves but reduced the contents of indole acetic acid (IAA) and gibberellic acid (GA); biochar amendment counteracted the impact of drought. The findings of the study indicate that biochar amendment can enhance soybean growth by modulating the plant physiology and biochemistry under drought stress. [ABSTRACT FROM AUTHOR]

Legumes being a major source of protein have a wide range of economic importance. But the major constraints in growing legumes are poor germination, seedling emergence, non uniform stand establishment and crop mortality leading to lower pulse productivity. Thus, pre-sowing seed treatments are critical parameters which attribute to efficient plant growth and high yield. Uniform seed germination, seedling growth and uniform establishment are the critical stages during the growth of crops. Seed priming is a very promising presowing treatment employed to improve seed germination, better crop establishment, enhance the seed quality and induces tolerance against biotic and abiotic stresses in plants thereby providing a balanced healthy diet to the citizens. Priming is a cost effective and feasible strategy involving controlled hydration of seeds followed by drying to stimulate the pre-germinative metabolic activities to occur promoting rapid germination of seedlings, break dormancy and enhance crop yield. Enzymatic, metabolic and biochemical processes of the primed seeds attributes to rapid and uniform seedling emergence. Seed priming methods comprises of conventional methods including hydro priming, osmopriming, biopriming, chemical priming and the advanced methods including nano priming and priming with physical agents. In this review paper, the underlying physiological, biochemical and molecular aspects of priming in pulses were discussed. [ABSTRACT FROM AUTHOR]

Legumes have important nutritional and economic values, but their production faces continuous cropping obstacles that seriously affect their yield formation. In order to reduce the negative impact of the continuous cropping obstacles of legumes, it is necessary to understand the response mechanisms of legumes to continuous cropping, the causes of continuous cropping obstacles and the measures to alleviate continuous cropping obstacles. This review aimed to identify the current knowledge gap in the field of continuous cropping obstacles of legumes and provide direction and focus for future research. The continuous cropping obstacles of legumes start with soil degradation, leading to oxidative stress in the plants. This triggers the expression of plant-hormone- and signal-molecule-related genes, activating the defense system and causing continuous cropping obstacles. Although there has been progress in researching these challenges in legume crops, many questions remain. We believe that the exploration of molecular mechanisms of legume crops responding to continuous cropping, rhizosphere signal exchange and soil environment repair mechanisms after long-term continuous cropping of soybean, and the excavation of candidate genes and functional loci related to continuous cropping obstacles in legume crops are breakthroughs for proposing effective continuous cropping obstacle management strategies in the future. [ABSTRACT FROM AUTHOR]

The article discusses the historical significance and ongoing relevance of platelet physiology and biochemistry in the field of thrombosis and hemostasis. It highlights the early discoveries of platelets as distinct blood cells involved in clotting and describes the development of various methods to study platelet function. The article also emphasizes the recent understanding of platelets' role beyond thrombosis and hemostasis, including their involvement in immune responses, tumor promotion, and metastasis. The importance of incorporating new technologies, such as -omics approaches, for studying platelet biology is also mentioned. The article concludes by noting the continued interest in platelet physiology, as evidenced by the popularity of recent papers on the topic. [Extracted from the article]

The experiment was implemented to assess the influence of dietary supplementation of laying quails with creatine monohydrate (CrM), L-carnitine (CAR) and their mixture (CrMCAR) as antioxidants against oxidative stress (OS) induced by 2.5 ppm lead acetate (LA) in drinking water on productive, physiological and microbial aspects. In total, 400 laying quail females at 10 wk of age were divided into a randomized design with 5 groups and 4 replicates of 20 birds each. Birds were fed ad libitum with a balanced diet for 8 wk. The control group was kept under no-stress conditions and was given fresh water without any additives (G1). While birds in other groups were exposed to OS induced experimentally by 2.5 ppm LA in drinking water with no feed additive (G2) or supplemented with 500 mg/kg CrM (G3) or 500 mg/kg CAR (G4) or combination of 250 mg/kg each of CrM and CAR (CrMCAR, G5) to feed mixture. Compared to G2, G5 demonstrated the reduction (P ≤ 0.05) of feed conversion ratio, feed intake, mortality and ileal total coliform, as well as serum and egg malondialdehyde and serum lipid hydroperoxide, uric acid, glucose, cholesterol, enzymatic activities (alanine aminotransferase, aspartate transaminase, alkaline phosphatase, creatine phosphokinase, γ-glutamyl transferase), and heterophils/lymphocytes ratio. In the meanwhile, there was an increase (P ≤ 0.05) in egg production, egg mass, and weight with the improvement of egg quality, serum sex hormones level and ileal lactic acid bacteria for G5 followed by G4 and G3. Moreover, G5 enhanced (P ≤ 0.05), the total antioxidant capacity of egg and serum glutathione, superoxide dismutase, catalase, glutathione peroxidase, protein and calcium levels. Therefore, dietary CrMCAR, CAR and CrM have analogous influence to control by improving the antioxidant and physiological parameters which resulted in better productive performance and egg characteristics of stressed quails. These antioxidants, especially in their equal combination, are beneficial to alleviate oxidative stress incidence and can be recommended for poultry feeding under various aspects of environmental stresses. [ABSTRACT FROM AUTHOR]