Search Results (1,644)

Saline–alkaline soils are becoming prevalent across the globe, decreasing the availability of forage for animals and threatening sustainable animal production. This study evaluated the effects of a NaCl-supplemented alfalfa-based total mixed ration, simulating saline–alkaline soil conditions, on intake, the utilization of nutrients, antioxidant levels, and rumen fermentation. A 60-day feeding trial with 24 AOHU lambs (Australian White × Hu) compared a control diet (0.43% NaCl) with the NaCl-supplemented group (1.71% NaCl). Digestibility trials were conducted in metabolic cages for the collection of total feces and urine. Blood samples were taken at 0, 30, and 60 days for serum analysis, and slaughter samples (liver, kidney, rumen tissue, and rumen fluid) were taken for physiological, biochemical, and histological evaluation. The NaCl alfalfa-based TMR markedly increased liver and kidney weights. The rumen muscle layer thickened in the NaCl group. The ruminal ammonia nitrogen (NH₃-N), ruminal microbial crude protein (MCP) synthesis, and glucogenic/branched-chain VFAs increased, indicating enhanced proteolysis, microbial protein synthesis, and energetically efficient fermentation. Serum total protein and albumin also rose over time in the NaCl group, reflecting increased nitrogen retention, while superoxide dismutase and glutathione peroxidase activity rose considerably by day 60, reflecting increased antioxidant defense. Furthermore, nitrogen intake, digestibility, and retention were improved in the NaCl group along with augmented digestible and metabolizable energy (28.47 vs. 13.93 MJ/d and 24.68 vs. 11.58 MJ/d, respectively) and gross energy digestibility (78.13% vs. 67.10%). Although NaCl-based alfalfa TMR cannot fully emulate naturally salt-stressed forages, these results indicate that the NaCl alfalfa-based diets improved rumen fermentation, energy yields, and antioxidant enzyme activity without impairing electrolyte balance. These findings suggest that NaCl-supplemented alfalfa-based TMRs, with a salt content comparable to that of alfalfa hay grown under saline–alkaline conditions, could support environmentally sustainable meat production in salt-stressed regions. Full article

The unimolecular alkene elimination reaction class of fatty acid alkyl esters (FAAEs) is a crucial component in the low-temperature combustion mechanism for biodiesel fuels. However, thermo-kinetic parameters for this reaction class are scarce, particularly for the large-size molecules over four carbon atoms and intricate branched-chain configurations. Thermo-kinetic parameters are essential for constructing a reaction mechanism, which can be used to clarify the chemical nature of combustion for biodiesel fuels. In this paper, the B3LYP method, in conjunction with the 6-311G(d,p) basis set, is used to carry out geometry optimization of the species participating in the reactions. Frequency calculations are further executed at the same level of theory. Additionally, coupled with the 6-311G(d,p) basis set, the B3LYP method acts as the low-level ab initio approach, while the Gaussian-4 (G4) composite method serves as the high-level ab initio approach within the isodesmic reaction correction scheme. The CCSD(T) approach is employed to verify the consistency of the electronic energy ascertained through the G4 method. The isodesmic reaction method (IRM) is used to obtain the energy barriers and reaction enthalpies for unimolecular alkene elimination reaction class of FAAEs. Based on the reaction class transition state theory (RC-TST), high-pressure-limit rate coefficients were computed, with asymmetric Eckart tunneling corrections applied across 500~2000 K temperature range. Rate rules at the high-pressure-limit are obtained through the averaging of rate coefficients from a representative collection of reactions, which incorporate substituent groups and carbon chains with different sizes and lengths. Ultimately, the energy barriers, reaction enthalpies, and rate rules at the high-pressure-limit and kinetic parameters expressed as (A, n, E) are supplied for developing the low-temperature combustion mechanism of biodiesel fuels. Full article

UV-C radiation has emerged as a germicidal agent against pathogens, particularly following the COVID-19 pandemic. While UV-C effectively reduces cross-contamination in hospitals, it induces photodegradation in polymer devices, potentially damaging and posing risks to patient safety. Therefore, it is crucial to detect the effects of UV-C photodegradation on early stages, as well as the effects of prolonged UV-C exposure. In this study, we investigated the UV-C photodegradation (254 nm, 471 kJ/mol) of isotactic polypropylene homopolymer (PP), commonly used in medication packaging. The impact of UV-C on PP was evaluated through rheology and infrared spectroscopy. Surface energy was measured by the contact angles formed by drops of water and diiodomethane. The effects of photodegradation on the polymer’s morphology were examined using scanning electron microscopy, and the melting temperature and crystallinity by differential scanning calorimetry. Lastly, the effect of UV-C on molecular mobility was studied using ¹H Time Domain Nuclear Magnetic Resonance (¹H TD-NMR). These techniques proved to be valuable tools for identifying the early stages of UV-C photodegradation, and ¹H TD-NMR was a sensitive method to identify the chain branching as a photodegradation product. This study highlights the impact of UV-C on PP photodegradation and hence the importance of understanding UV-C-induced degradation. Full article

Nitrogen metabolism in the human body is in a strictly balanced state, which is disturbed in pathologies, including breast cancer. The state of nitrogen balance can be judged by the content of urea and the amount of branched-chain amino acids (BCAAs) (Val, Leu, and Ile), glutamine (Gln), and glutamate (Glu). The study involved 1438 people, including patients with breast cancer (n = 543), fibroadenomas (n = 597), and healthy controls (n = 298). Saliva samples were collected from all patients before treatment, and urea levels were determined in all 1438 samples. Salivary levels of BCAAs, Gln, and Glu were determined in 116 patients with breast cancer, 24 with fibroadenomas, and 25 healthy volunteers. An increase in the concentration of urea in saliva was shown in breast cancer, most pronounced in luminal molecular biological subtypes: luminal A 10.46 [7.69; 12.62] mmol/L (p < 0.0001), luminal B HER2-negative 9.52 [6.72; 12.52] mmol/L (p = 0.0198), and luminal B HER2-positive 8.26 [5.27; 12.07] mmol/L. The Gln/Glu ratio increased in the saliva of the control group (5.43 [3.30; 10.5]) compared with breast cancer (2.22 [0.84; 5.40], p = 0.0094) and fibroadenomas (1.94 [0.89; 6.05], p = 0.0184). For luminal B HER2-positive and TNBC, the Gln/Glu ratio increased sharply to 8.23 [3.24; 10.9] (p = 0.0327) and 11.2 [4.28; 15.2] (p < 0.0001) compared with healthy controls. Thus, an increased Gln/Glu ratio in saliva may characterize a more aggressive subtype of breast cancer. Full article

Background/Objectives: The interplay between host metabolism and gut microbiota is central to the pathophysiology of metabolic diseases, including metabolic dysfunction-associated steatotic liver disease (MASLD). In this study, we investigated the underexplored fecal host–microbiota co-metabolism profile of male and female Wistar rats after 21 weeks of high-fat diet (HFD), a model previously validated for early MASLD. Methods: Using ¹H-NMR spectroscopy, we detected and quantified metabolites in fecal samples associated with hepatic metabolism beyond short-chain fatty acids (SCFAs), such as energy-related metabolites, amino acid turnover, branched-chain amino acid (BCAA) catabolism, and microbial fermentation. Results: Distinct metabolic signatures were identified according to diet and sex, and statistical analysis was performed. Notably, alterations were observed in bile acids (BAs) such as cholate and glycocholate, suggesting disruptions in enterohepatic circulation. The presence of fucose, a sugar linked to liver pathology, was also elevated. Energy-related metabolites indicated a shift from lactate production to increased acetoacetate and malonate levels, implying redirection of pyruvate metabolism and inhibition of the TCA cycle. BCAA derivatives such as 3-methyl-2-oxovalerate and 3-aminoisobutyrate were altered, supporting earlier findings on disrupted amino acid metabolism under HFD conditions. Furthermore, microbial metabolites including methanol and ethanol showed group-specific differences, suggesting shifts in microbial activity. Conclusions: These findings complement previous longitudinal data and provide a functional interpretation of newly identified metabolites. These metabolites, previously unreported, are now functionally contextualized and linked to hepatic and microbial dysregulation, offering novel biological insights into early MASLD mechanisms. Full article

Acetolactate synthase (ALS) is an important enzyme in plant branched-chain amino acid biosynthesis and the target of several major herbicide classes. Despite its agronomic importance, the role of ALS genes in stress adaptation in the invasive weed Amaranthus palmeri remains unstudied. In this study, four ApALS genes with high motif conservation were identified and analyzed in A. palmeri. Phylogenetic analysis classified ApALS and other plant ALS proteins into two distinct clades, and the ApALS proteins were predicted to localize to the chloroplast. Gene expression analysis demonstrated that ApALS genes are responsive to multiple stresses, including salt, heat, osmotic stress, glufosinate ammonium, and the ALS-inhibiting herbicide imazethapyr, suggesting roles in both early and late stress responses. Herbicide response analysis using an Arabidopsis thaliana ALS mutant (AT3G48560) revealed enhanced imazethapyr resistance, associated with higher chlorophyll retention. Furthermore, high sequence homology between AT3G48560 and ApALS1 suggests a conserved role in protecting photosynthetic function during herbicide stress. This study provides the first comprehensive analysis of the ALS gene family in A. palmeri and offers important insights into its contribution to stress resilience. These findings establish a vital foundation for developing novel strategies to control this pervasive agricultural weed and present potential genetic targets for engineering herbicide tolerance in crops. Full article

Background: Maple syrup urine disease (MSUD) is a genetic disorder caused by mutations in the branched-chain α-ketoacid dehydrogenase (BCKDH) complex, leading to toxic buildup of branched-chain amino acids (BCAAs) and their ketoacid derivatives. While newborn screening (NBS) and molecular testing are standard diagnostic tools, they face challenges such as delayed results and false positives. Untargeted metabolomics has emerged as a complementary approach, offering comprehensive metabolic profiling and potential for novel biomarker discovery. We previously applied untargeted metabolomics to neonates with MSUD, identifying distinct metabolic signatures. Objective: This follow-up study investigates metabolic changes and biomarkers in pediatric MSUD patients and explores shared dysregulated metabolites between neonatal and pediatric MSUD. Methods: Dried blood spot (DBS) samples from pediatric MSUD patients (n = 14) and matched healthy controls (n = 14) were analyzed using LC/MS-based untargeted metabolomics. Results: In pediatric MSUD, 3716 metabolites were upregulated and 4038 downregulated relative to controls. Among 1080 dysregulated endogenous metabolites, notable biomarkers included uric acid, hypoxanthine, and bilirubin diglucuronide. Affected pathways included sphingolipid, glycerophospholipid, purine, pyrimidine, nicotinate, and nicotinamide metabolism, and steroid hormone biosynthesis. Seventy-two metabolites overlapped with neonatal MSUD cases, some exhibiting inverse trends between age groups. Conclusion: Untargeted metabolomics reveals that the metabolic profiling of MCUD pediatric patients different from that of their controls. Also, there are valuable age-specific and shared metabolic alterations in MSUD, enhancing the understanding of disease progression in MSUD patients. This supports its utility in improving diagnostic precision and developing personalized treatment strategies across developmental stages. Full article

Background/Objectives: Aging and metabolic disorders are associated with a decline in muscle function, referred to as age-related sarcopenia. The underlying mechanisms of sarcopenia include cellular senescence, imbalanced protein homeostasis, accumulation of oxidative and inflammatory stressors, and mitochondrial dysfunction. Probiotic supplementation improves the gut microbiome and enhances muscle function via the gut–muscle axis. However, details of molecular mechanisms and the development of an appropriate treatment are under active investigation. Methods: We have examined the effects of Lactiplantibacillus plantarum LM1001, a probiotic that reportedly improves the digestibility of branched-chain amino acids in myocyte cultures, but exactly how it contributes to muscle structure and function remains unclear. Results: We show that aged mice (male C57BL6/J) fed a high-fat diet (HFD) exhibit weak muscle strength, as reflected by a reduction in grip strength. LM1001 supplementation increases muscle strength and restores myofibril size, which has been altered by HFD in aged mice. Expression of myogenic proteins is increased, while protein markers for muscle atrophy are downregulated by LM1001 treatment via the IGF-1/Akt/FoxO3a pathway. LM1001 improves gut microbiota that are altered in aged HFD-fed mice, by increasing their abundance in beneficial bacteria, and efficiently maintains the epithelial lining integrity of the large intestine. Conclusions: We conclude that LM1001 supplementation serves a beneficial role in patients suffering from sarcopenia and metabolic disorders, improving their muscle function, gut microbiota, and intestinal integrity. Full article

In this paper, we propose a formulation of the permutation flow and job shop scheduling problems using special recursive functions and show its equivalence to the existing classical formulation. Equivalence is understood in the sense that both ways of defining the problem describe the same set of feasible schedules for each pair of jobs and machine numbers. In this paper, the apparatus of recursive functions is used to describe and solve three problems: permutation flow shop; permutation flow shop with the addition of the ‘and’ predicate extending the machine chain to an acyclic graph; and permutation job shop. The predicate ‘and’ allows the description of the flow shop with assembly operation tasks. Recursive functions have a common domain and range. To calculate an optimal schedule for each of these three problems, a branch and bound method is considered based on a recursive function that implements a job swapping algorithm. The complexity of the optimization algorithm does not increase compared to the non-recursive description of the PFSP. This article presents some results for the calculation of optimal schedules on several test instances. It is expected that the new method, based on the description of recursive functions and their superposition, will be productive for formulating and solving some extensions of scheduling problems that have practical significance. Full article

The curing of silicone networks from dimethylsilanediol and methylsilanetriol chainbuilder–crosslinker precursor mixtures is investigated from combined quantum/molecular mechanics simulations. Upon screening different crosslinker content from 5 to 15%, we provide a series of atomic-resolution bulk models all featuring 98–99% curing degree, albeit at rather different arrangement of the chains and nodes, respectively. To elucidate the nm scale alignment of the polymer networks, we bridge scales from atomic simulation cells to graph theory and demonstrate the analyses of 3-dimensional percolation of -O-Si-O- bonds, polydimethylsiloxane branching characteristics and the interpenetration of loops. Our findings are discussed in the context of the available experimental data to relate heat of formation, curing degree and elastic properties to the molecular scale structural details—thus promoting the in-depth understanding of silicone resins. Full article

The human gut microbiota constitutes the microbial ecosystem within the human gut. It consists of trillions of mostly prokaryotic microorganisms living in the gut lumen, which have an active metabolic role in the regulation of many host functions, including vitamin synthesis and energy extraction from indigestible fiber. Host diet is the main driver of gut microbial composition and metabolic output. Athletes and athletic individuals often supplement their diet with legal nutritional supplements to enhance performance, especially at the elite level. This review summarizes and critically comments on key evidence of the effects of the most common athletic nutritional supplements on the human gut microbiota, based on the most recent literature. We cover suggested changes in bacterial diversity or the relative abundance of specific bacterial taxa and effects of nutritional supplementation on bacterial metabolism. We focus on the molecular pathways involved, we discuss contrasting results and inconsistencies, and we note limitations and challenges in the field. We conclude with a summary of evidence, proposals, and future directions. Full article

Polysaccharides derived from green algae have garnered significant attention owing to their distinctive structural characteristics and biological activities. In particular, sulfated polysaccharides from these algae represent a promising frontier in the discovery of novel therapeutic agents. In this present study, a sulfated galactan from Caulerpa taxifolia, designated SGC, was obtained by dilute alkali extraction and chromatographic purification. On the basis of chemical and spectroscopic analyses, the backbone of SGC was constituted by a backbone of →3)-β-d-Galp-(1→ with sulfate substitution at the C-2 and a branch on C-6. The side chains contained →6)-β-d-Galp(2SO₄)-(1→, →6)-β-d-Galp(3OMe)-(1→ and →3)-β-d-Galp(4,6-Pyr)-(1→ units. SGC possessed strong hypoglycemic activity in vitro, as evaluated by an assay of α-amylase inhibition. The anti-diabetic activity of SGC in vivo was further investigated using T2DM mice induced by high-fat diet combined with streptozotocin. The results indicated that SGC markedly restored body weight, reduced fasting blood glucose and possessed a significant glucose-regulating effect. Furthermore, SGC effectively increased insulin sensitivity and mitigated insulin resistance. Additionally, SGC effectively regulated lipid metabolism and alleviated oxidative stress. Notably, SGC ameliorated liver and pancreas damage induced by high-fat diet combined with streptozotocin. The investigation demonstrates that SGC is a unique sulfated galactan and has potential as a novel anti-diabetic agent. Full article

The current work is driven by applying circular principles, and it investigated the potential recyclability of polybutylene succinate (PBS) containing brewer’s spent grain filler (BSGF, 30 wt%) in comparison to the recyclability of pure PBS. PBS is much more stable than the PBS/BSGF composite during processing cycles. Typically, thermomechanical degradation induces radical formation and branching of the macromolecular chain in PBS. Furthermore, PBS becomes less hydrophilic (by 53%, reaching 84°, approaching the 90° threshold), and its surface roughness increases by about 38% after five processing cycles. BSGF increases the viscosity of the melt, especially at low frequencies, and stabilizes the melt in the PBS/BSGF, which has lower torque variations during processing compared to pure PBS. Furthermore, BSGF in r-PBS/BSGF increases both hydrophilicity (by about 15%, from 75° to 64°) and surface roughness (by about 17%) after five processing cycles of the solid bio-composite and limits the formation of carboxylic groups during thermomechanical degradation. PBS is recyclable five times because it maintains its properties unchanged during extrusion cycles. At least two reprocessing steps are required for PBS/BSGF to obtain an optimal dispersion of BSGF, which can be re-extruded approximately three times. PBS/BSGF after four and five extrusion steps shows increased rigidity (E_t PBS/BSGF > E_t PBS) and reduced ductility (ε_b PBS/BSGF < ε_bt PBS), which could limit the recyclability of the PBS-based composite. Full article

Although hydrocarbon-degrading bacteria utilize a wide range of alkanes, the global metabolic features and regulatory mechanisms governing their growth on alkanes with different chain lengths remain incompletely elucidated. In this study, we analyzed the comparative transcriptomics of a salt-tolerant bacterium, Dietzia sp. CN-3, to investigate molecular adaptations and metabolic processes when grown on n-hexadecane (C₁₆), branched alkane (pristane), and glucose. A total of 1766 differentially expressed genes (DEGs) were identified in the C₁₆ group compared to the glucose control, with 1024 (58.0%) being upregulated and 742 (42.0%) being downregulated. Notably, the pristane group exhibited 1542 DEGs, of which 488 (31.6%) were upregulated and 1054 (68.4%) were downregulated. Our results demonstrate that C₁₆ and pristane induced common genes of alkane hydroxylation in the core alkane degradation pathway, while eliciting distinct transcriptional patterns of genes involved in lipid metabolism, energy metabolism, metal ion transportation, cell surface composition biosynthesis, and transcription regulation. The findings reveal that CN-3 employs diverse metabolic strategies to adapt to alkanes with different chain lengths, displaying considerable metabolic plasticity. This study significantly enhances our understanding of molecular adaptation of bacteria to hydrocarbon-containing environments and may provide valuable information for further studies of petroleum hydrocarbon bioremediation. Full article

Brown adipose tissue (BAT) has shifted from being considered a transient thermogenic organ of infancy to a metabolically dynamic and multifunctional tissue throughout life. Histologically and developmentally distinct from white and beige adipocytes, BAT originates from a myogenic lineage and is characterised by a high mitochondrial density, multilocular lipid droplets, and abundant sympathetic innervation. Its defining function, non-shivering thermogenesis, is mediated by uncoupling protein 1 (UCP1) and complemented by alternative mechanisms such as futile creatine and calcium cycling. Beyond heat production, thermogenic fat is crucial in regulating whole-body metabolism. It contributes to glucose, lipid, and branched-chain amino acid homeostasis, and engages in endocrine and paracrine signalling through a rich secretome of batokines, lipid mediators, and extracellular vesicle-bound microRNAs. These signals orchestrate crosstalk with the liver, skeletal muscle, pancreas, and immune system, enhancing insulin sensitivity, vascularisation, and anti-inflammatory responses. Brown/Beige fat also exhibits notable anti-fibrotic properties and supports adipose tissue remodelling, maintaining structural and functional plasticity under metabolic stress. This review offers a comprehensive synthesis of thermogenic adipose tissue biology, integrating its structural, developmental, and molecular features with its expanding physiological functions, highlighting its pivotal role in energy balance as well as its emerging therapeutic potential in obesity, type 2 diabetes, and related metabolic disorders. Full article