Search Results (51)

This article focuses on the fire safety risks associated with conventional glass–aluminum façades—with a particular focus on stick and unitized curtain walling systems—providing an overview of possible fire spread mechanisms, considering the role of the curtain wall in maintaining compartmentation at the spandrel zone. First, it analyzes some of the relevant requirements of different European building regulations. Then, it provides a test evidence-based critical analysis of the gaps and loopholes in the relevant fire resistance standard for partial curtain wall configurations (EN 1364-4), where the evaluation of the propagation within the façade system is not necessarily considered in the fire-resistant spandrel zone. Finally, it presents a proposal for addressing these gaps in the form of a theoretical concept for a new test configuration and additional assessment criteria. This is followed by an initial experimental analysis of the concept. The standard testing campaign showed that temperature rise in mullions can exceed 180 °C after 30 min if limiting measures are not considered in the façade design. However, this can be only detected if framing is in the non-exposed area of the sample, being part of the evaluation surface. Meanwhile, differences are detected between the results from standard and new assessment criteria in the new configuration proposed, including a more rapid temperature rise for framing elements (207 K in a second level mullion at minute 90) than for the common non-exposed assessment surface of the sample (172 K at the same time) in cases where cavities are not protected. Accordingly, the proposed configuration successfully detected vertical temperature transfer within mullions, which can remain undetected in standard EN 1364-4 tests, highlighting the potential for fire spread even in EI120-rated assemblies. Full article

Four new minor monosulfated triterpene penta- and hexaosides, cladolosides S (1), S₁ (2), T (3), and T₁ (4), were isolated from the Vietnamese sea cucumber Cladolabes schmeltzii (Sclerodactylidae, Dendrochirotida). The structures of the compounds were established based on extensive analysis of 1D and 2D NMR spectra as well as HR-ESI-MS data. Cladodosides S (1), S₁ (2) and T (3), T₁ (4) are two pairs of dehydrogenated/hydrogenated compounds that share identical carbohydrate chains. The oligosaccharide chain of cladolosides of the group S is new for the sea cucumber glycosides due to the presence of xylose residue attached to C-4 Xyl1 in combination with a sulfate group at C-6 MeGlc4. The oligosaccharide moiety of cladolosides of the group T is unique because of the position of the sulfate group at C-3 of the terminal sugar residue instead of the 3-O-Me group. This suggests that the enzymatic processes of sulfation and O-methylation that occur during the biosynthesis of glycosides can compete with each other. This can presumably occur due to the high level of expression or activity of the enzymes that biosynthesize glycosides. The mosaicism of glycoside biosynthesis (time shifting or dropping out of some biosynthetic stages) may indicate a lack of compartmentalization inside the cells of organism producers, leading to a certain degree of randomness in enzymatic reactions; however, this also offers the advantage of providing chemical diversity of the glycosides. Analysis of the hemolytic activity of a series of 26 glycosides from C. schmeltzii revealed some patterns of structure–activity relationships: the presence or absence of 3-O-methyl groups has no significant impact, hexaosides, which are the final products of biosynthesis and predominant compounds of the glycosidic fraction of C. schmeltzii, are more active than their precursors, pentaosides, and the minor tetraosides, cladolosides of the group A, are weak membranolytics and therefore are not synthesized in large quantities. Two glycosides from C. schmeltzii, cladolosides D (18) and H₁ (26), display selectivity of cytotoxic action toward triple-negative breast cancer cells MDA-MB-231, while remaining non-toxic in relation to normal mammary cells MCF-10A. Quantitative structure–activity relationships (QSAR) were calculated based on the correlational analysis of the physicochemical properties and structural features of the glycosides and their hemolytic and cytotoxic activities against healthy MCF-10A cells and cancer MCF-7 and MDA-MB-231 cell lines. QSAR highlighted the complexity of the relationships as the cumulative effect of many minor contributions from individual descriptors can have a significant impact. Furthermore, many structural elements were found to have different effects on the activity of the glycosides against different cell lines. The opposing effects were especially pronounced in relation to hormone-dependent breast cancer cells MCF-7 and triple-negative MDA-MB-231 cells. Full article

Silicon dioxide (SiO₂) foliar application offers a promising strategy for enhancing lettuce (Lactuca sativa L.) resilience under temperature extremes, salinity, and drought stress. This study investigated the effects of SiO₂ treatment on three lettuce cultivars exposed to varying temperature, salinity, and drought conditions in a controlled growth chamber environment. Silicon treatment (3.66 mM) significantly enhanced plant biomass under suboptimal (15 °C), optimal (20 °C), and salinity stress conditions. Notably, the SiO₂ effect was most positive under severe salinity stress (100 mM NaCl), where its application increased plant weight together with chlorophyll and anthocyanin content. When increasing SiO₂ concentrations from 0 to 29.30 mM were tested, optimal results to alleviate severe salinity stress were consistently observed at 3.66 mM, with peak performance in fresh weight, plant diameter, chlorophyll, and anthocyanin content. Higher SiO₂ concentrations progressively diminished these beneficial effects, with 29.30 mM treatment leading to reduced growth and increased leaf chlorosis. Comprehensive mineral composition analysis revealed complex interactions between silicon treatment and elemental profiles at 100 mM salinity stress. At 3.66 mM SiO₂, plants accumulated the highest levels of both K (20,406 mg/kg dry weight, DW) and Na (16,185 mg/kg DW) while maintaining the highest K/Na ratio (1.26). This suggests that Si enhances cellular ion compartmentalization rather than exclusion mechanisms, allowing plants to manage higher total ion content better while minimizing cytoplasmic damage. Drought stress conditions unexpectedly revealed negative impacts from 3.66 mM SiO₂ application, with decreased plant fresh weight at moderate (50% soil water content, SWC) and severe (30% SWC) water limitations, though results were statistically significant only under severe drought stress. The study highlights silicon’s potential as a stress mitigation agent, particularly under salinity stress, while emphasizing the need for concentration-specific and stress-specific approaches. These findings suggest that foliar SiO₂ application could be a valuable tool for enhancing lettuce crop productivity under both optimal and challenging environmental conditions, with future research warranting field validation and full market maturity assessments. Full article

Cadmium (Cd) accumulation in plants hinders their growth and development while posing significant risks to human health through food chain transmission. Glycyrrhiza uralensis Fisch. (G. uralensis) is a medicinal plant valued for its roots and plays a crucial role in harmonizing various herbs in traditional Chinese medicine prescriptions. However, widespread Cd contamination in soil limits safe cultivation and application. Selenium (Se), a beneficial element in plants, can regulate plant growth by enhancing carbon metabolism and reducing heavy metal uptake. This study aimed to elucidate the protective mechanisms of Se application in licorice plants exposed to 20 μM Cd. Experiments with 1 and 5 μM of Se revealed that 1 μM of Se provided the best protective effects. This concentration reduced the Cd²⁺ content in the roots of G. uralensis, while significantly increasing plant biomass, root length, SPAD value, and contents of K⁺, Ca²⁺, and S²⁻. Additionally, the treatment reduced the malondialdehyde (MDA) content by 30.71% and 58.91% at 12 h and 30 d, respectively. The transcriptome analysis results suggest that Se mitigated Cd toxicity by enhancing carbon metabolism, regulating the AsA-GSH cycle, reducing Cd absorption, promoting Cd transport and compartmentalization, and modulating Cd resistance-associated transcription factors. These findings clarify the mechanisms by which Se alleviates Cd toxicity in G. uralensis and offer a promising strategy for the safe cultivation and quality control of medicinal herbs in Cd-contaminated soils. Full article

Heavy metal toxicity leads to impaired crop growth and reduced crop yields and product quality by disrupting plant nutrient uptake, inhibiting development, inducing oxidative stress, and causing cellular toxicity. Arbuscular mycorrhizal fungi (AMF) can play a crucial role in crops’ adaptation to manganese (Mn) toxicity by regulating nutrient uptake and altering subcellular compartmentalization. The present study examines the influence of intact extraradical mycelia (ERMs) from native AMF on wheat (Triticum aestivum) grown in Mn-toxic soil, with a focus on the tissue-specific and subcellular Ca, Mg, P, and Mn distribution. Wheat cultivated in soil pre-colonized using an intact ERM associated with Lolium rigidum or Ornithopus compressus exhibited enhanced growth and improved P contents. During the first week of growth, the Mn concentrations increased in the wheat’s roots and shoots, but Mn was subsequently reduced and sequestered within the cell wall. In contrast, in the absence of an intact ERM, the Mn accumulation in wheat followed an apparent continuous time-course pattern. AMF-mediated cell wall sequestration seems to contribute to Mn detoxification by limiting excessive cytoplasmic accumulation. Furthermore, AMF-driven changes in the element distribution suggest a dynamic response, wherein an early-stage nutrient uptake transitions into a long-term protective mechanism. These findings highlight the potential of AMF in mitigating Mn stress in crops, providing insights for sustainable agriculture and soil remediation strategies. Full article

The detailed study of the morphology and morphometrics of the auditory ossicles in swine became a topic for investigation due to their resemblance to the human ear. The methods used in this study cover the typical macroscopical investigation of gross morphology: a detailed metrical and histological assessment through H&E standard protocol on auditory ossicles originating from eight pig fetuses originating from four distinctive sows. The ossicular assembly in the malleus, incus and stapes present in 66-day fetuses shows all the features generally described in swine. The malleus comprises two uneven laminae of mineralized hyaline cartilage and a medullary cavity. The areas of the head and neck show a high degree of vascularization. The incus has two similar cortical fascicles separated by a compartmentalized medullary cavity, with the highest degree of mineralization found at the distal part of the long process. Stapes show an early degree of mineralization at the level of the crura, lacking medullary cavities. The ossicular chain shows typical morphological elements, similar to adults, and from a dimensional perspective, our investigations point to an uneven degree of development of the ossicles, according to gestational age: the malleus and stapes reach almost 80% and the incus about 50–60% of their adult sizes. Full article

Salt is a potent abiotic stress that arrests plant growth by impairing their physio-biochemical and molecular processes. However, it is unknown how the ABA signaling system and vacuolar-type Na⁺/H⁺ antiporter proteins induce stress tolerance in wheat (Triticum aestivum L.) seedlings. The present study aimed to identify salt-responsive proteins and signaling pathways involved in the resistance of wheat to salt stress. We explored the proteome profile, 20 amino acids, 14 carbohydrates, 8 major phytohormones, ion content, and salt tolerance genes in wheat (Triticum aestivum L., cv.) under 200 mM NaCl with control plants for six days. The results showed that amino acids such as alanine, serine, proline, glutamine, and aspartic acid were highly expressed under salt stress compared with control plants, suggesting that amino acids are the main players in salinity tolerance. The ABA signaling system was activated in response to salinity stress through the modulation of protein phosphatase 2C (PP2C) and ABA-responsive element binding factor (ABF), resulting in an ABA-mediated downstream response. Additionally, the vacuolar-type Na⁺/H⁺ antiporter was identified as a key protein in salt stress tolerance via compartmentalizing Na⁺ in the vacuole. Furthermore, a significant increase in the abundance of the 14-3-3 protein was noticed in salt-fed plants, suggesting that this protein plays an important role in Na⁺ compartmentalization. Moreover, up-regulation of ascorbate peroxidase (APX), glutathione-S-transferase (GST), and thioredoxin-scavenged reactive oxygen species resulted in improved plant growth under salt stress. These data will help to identify salt-responsive proteins that can be used in future breeding programs to develop salt-tolerant varieties. Full article

Atopic dermatitis (AD) is a common inflammatory skin disease, in particular among infants, and is characterized, among other things, by a modification in fatty acid and ceramide composition of the skin’s stratum corneum. Palmitic acid and stearic acid, along with C₁₆-ceramide and 2-hydroxy C₁₆-ceramide, occur strikingly in AD. They coincide with a simultaneous decrease in very long-chain ceramides and ultra-long-chain ceramides, which form the outermost lipid barrier. Ceramides originate from cellular sphingolipid/ceramide metabolism, comprising a well-orchestrated network of enzymes involving various ELOVLs and CerSs in the de novo ceramide synthesis and neutral and acid CERase in degradation. Contrasting changes in long-chain ceramides and very long-chain ceramides in AD can be more clearly explained by the compartmentalization of ceramide synthesis. According to our hypothesis, the origin of increased C₁₆-ceramide and 2-hydroxy C₁₆-ceramide is located in the lysosome. Conversely, the decreased ultra-long-chain and very long-chain ceramides are the result of impaired ELOVL fatty acid elongation. The suggested model’s key elements include the lysosomal aCERase, which has pH-dependent long-chain C₁₆-ceramide synthase activity (revaCERase); the NADPH-activated step-in enzyme ELOVL6 for fatty acid elongation; and the coincidence of impaired ELOVL fatty acid elongation and an elevated lysosomal pH, which is considered to be the trigger for the altered ceramide biosynthesis in the lysosome. To maintain the ELOVL6 fatty acid elongation and the supply of NADPH and ATP to the cell, the polyunsaturated PPARG activator linoleic acid is considered to be one of the most suitable compounds. In the event that the increase in lysosomal pH is triggered by lysosomotropic compounds, compounds that disrupt the transmembrane proton gradient or force the breakdown of lysosomal proton pumps, non-HLA-classified AGEP may result. Full article

Copper (Cu) is an essential nutrient for plant growth and development. This metal serves as a constituent element or enzyme cofactor that participates in many biochemical pathways and plays a key role in photosynthesis, respiration, ethylene sensing, and antioxidant systems. The physiological significance of Cu uptake and compartmentalization in plants has been underestimated, despite the importance of Cu in cellular metabolic processes. As a micronutrient, Cu has low cellular requirements in plants. However, its bioavailability may be significantly reduced in alkaline or organic matter-rich soils. Cu deficiency is a severe and widespread nutritional disorder that affects plants. In contrast, excessive levels of available Cu in soil can inhibit plant photosynthesis and induce cellular oxidative stress. This can affect plant productivity and potentially pose serious health risks to humans via bioaccumulation in the food chain. Plants have evolved mechanisms to strictly regulate Cu uptake, transport, and cellular homeostasis during long-term environmental adaptation. This review provides a comprehensive overview of the diverse functions of Cu chelators, chaperones, and transporters involved in Cu homeostasis and their regulatory mechanisms in plant responses to varying Cu availability conditions. Finally, we identified that future research needs to enhance our understanding of the mechanisms regulating Cu deficiency or stress in plants. This will pave the way for improving the Cu utilization efficiency and/or Cu tolerance of crops grown in alkaline or Cu-contaminated soils. Full article

The traditional concept of compartmentation guaranteed by fire resistance is mainly concerned with the problem of destructive internal spread potential. External convective spread potential pertains to the loss of compartmentation associated with windows and facade systems. As such, it is assumed that internal fire spread occurs following mechanisms of excessive heat conduction and/or successive failure of the compartment boundaries, which can be, in most cases, conservatively characterised using traditional methods of performance assessment such as fire resistance. Nevertheless, external fire spread represents a potentially more effective route by which fire can spread through the convective advancement of flames and hot gases. This is particularly important in cases such as timber construction, where the presence of exposed timber can result in increased convective spread potential and where loss of compartmentation can result in disproportionate consequences. A simplified compartment fire model is proposed with the objective of quantifying the fuel contribution of exposed timber elements to the compartment fire and determining the impact of variable percentages of exposed timber on the convective spread potential. The overall results show that the convective fire spread potential increases with the increasing percentage of available timber. Full article

Disease modifiers, whether from cancer, sepsis, systemic inflammation, or microbial pathogens, all appear to induce epithelial barrier leak, with induced changes of the Tight Junctional (TJ) complex being pivotal to the process. This leak—and the ensuant breakdown of compartmentation—plays a central role in disease morbidity on many levels. Accumulation of lung water in the luminal compartment of airways was a major driver of morbidity and mortality in COVID-19 and is an excellent example of the phenomenon. Increasing awareness of the ability of micronutrients to improve basal barrier function and reduce barrier compromise in pathophysiology may prove to be a low-cost, safe, and easily administered prophylactic and/or therapeutic option amenable to large populations. The growing appreciation of the clinical utility of supplemental doses of Vitamin D in COVID-19 is but one example. This narrative review is intended to propose a general theory on how and why micronutrients—at levels above normal dietary intake—successfully remodel TJs and improve barrier function. It discusses the key difference between dietary/Recommended Daily Allowance (RDA) levels of micronutrients versus supplemental levels, and why the latter are needed in disease situations. It advances a hypothesis for why signal transduction regulation of barrier function may require these higher supplemental doses to achieve the TJ remodeling and other barrier element changes that are clinically beneficial. Full article

14-3-3 proteins are widely distributed in eukaryotic cells and play an important role in plant growth, development, and stress tolerance. This study revealed nine 14-3-3 genes from the genome of Nitraria sibirica Pall., a halophyte with strong salt tolerance. The physicochemical properties, multiple sequence alignment, gene structure and motif analysis, and chromosomal distributions were analyzed, and phylogenetic analysis, cis-regulatory elements analysis, and gene transcription and expression analysis of Ns14-3-3s were conducted. The results revealed that the Ns14-3-3 gene family consists of nine members, which are divided into two groups: ε (four members) and non-ε (five members). These members are acidic hydrophilic proteins. The genes are distributed randomly on chromosomes, and the number of introns varies widely among the two groups. However, all genes have similar conserved domains and three-dimensional protein structures. The main differences are found at the N-terminus and C-terminus. The promoter region of Ns14-3-3s contains multiple cis-acting elements related to light, plant hormones, and abiotic stress responses. Transcriptional profiling and gene expression pattern analysis revealed that Ns14-3-3s were expressed in all tissues, although with varying patterns. Under salt stress conditions, Ns14-3-3 1a, Ns14-3-3 1b, Ns14-3-3 5a, and Ns14-3-3 7a showed significant changes in gene expression. Ns14-3-3 1a expression decreased in all tissues, Ns14-3-3 7a expression decreased by 60% to 71% in roots, and Ns14-3-3 1b expression increased by 209% to 251% in stems. The most significant change was observed in Ns14-3-3 5a, with its expression in stems increasing by 213% to 681%. The yeast two-hybrid experiments demonstrated that Ns14-3-3 5a interacts with NsVP1 (vacuolar H⁺-pyrophosphatase). This result indicates that Ns14-3-3 5a may respond to salt stress by promoting ionic vacuole compartmentalization in stems and leaves through interactions with NsVP1. In addition, N. sibirica has a high number of stems, allowing it to compartmentalize more ions through its stem and leaf. This may be a contributing factor to its superior salt tolerance compared to other plants. Full article

Colletotrichum spp. are ascomycete fungi and cause anthracnose disease in numerous crops of economic significance. The genomes of these fungi are distributed among ten core chromosomes and two to three minichromosomes. While the core chromosomes regulate fungal growth, development and virulence, the extent to which the minichromosomes are involved in these processes is still uncertain. Here, we discuss the minichromosomes of three hemibiotrophic Colletotrichum pathogens, i.e., C. graminicola, C. higginsianum and C. lentis. These minichromosomes are typically less than one megabase in length, characterized by containing higher repetitive DNA elements, lower GC content, higher frequency of repeat-induced point mutations (RIPMs) and sparse gene distribution. Molecular genetics and functional analyses have revealed that these pathogens harbor one conditionally dispensable minichromosome, which is dispensable for fungal growth and development but indispensable for fungal virulence on hosts. They appear to be strain-specific innovations and are highly compartmentalized into AT-rich and GC-rich blocks, resulting from RIPMs, which may help protect the conditionally dispensable minichromosomes from erosion of already scarce genes, thereby helping the Colletotrichum pathogens maintain adaptability on hosts. Overall, understanding the mechanisms underlying the conditional dispensability of these minichromosomes could lead to new strategies for controlling anthracnose disease in crops. Full article

Rabeprazole is a proton pump inhibitor that inhibits gastric acid production and increases gastric pH; it is widely used clinically as a treatment option for gastritis and gastric ulcers. However, information on the inter-individual variability of rabeprazole pharmacometrics, which is a key element in establishing its scientific clinical use, is still lacking. Particularly, the differences in pharmacokinetics between genders and the degree of variation in pharmacodynamics have not been clearly identified. Thus, the main purpose of this study was to explore any differences in rabeprazole pharmacokinetics between genders and to quantitatively predict and compare the effects of any differences in pharmacokinetics between genders on known pharmacodynamics using population pharmacokinetic–pharmacodynamic modeling. To compare pharmacokinetics and modeling data between genders, bioequivalence results were used simultaneously on healthy Korean men and women using the physiological and biochemical parameters derived from each individual. Pharmacodynamic modeling was performed based on the data of previously reported gastric pH changes in response to rabeprazole plasma concentrations, which was co-linked to the central compartmental bioavailable concentration in the population pharmacokinetic model. There was no significant difference in the level of rabeprazole exposure and elimination of plasma between genders following oral administration of 10 mg enteric-coated rabeprazole tablets; however, there was a clear delay in absorption in women compared to men. Additionally, a comparison of pharmacokinetic parameters normalized to body weight between genders showed that the maximum plasma concentrations were significantly higher in women than in men, again suggesting gender differences in rabeprazole absorption. The population pharmacokinetic profiles for rabeprazole were described using a three-sequential multi-absorption with lag time (T_lag) two-compartment model, whereas body surface area and gender were explored as effective covariates for absorption rate constant and T_lag, respectively. The effect of increased gastric pH due to plasma exposure to rabeprazole was explained using the Sigmoid Emax model, with the baseline as a direct response. The significantly longer rabeprazole T_lag in females delayed the onset of an effect by an average of 1.58 times (2.02–3.20 h), yet the overall and maximum effects did not cause a significant difference within 15%. In the relative comparison of the overall efficacy of rabeprazole enteric-coated tablet administration between genders, it was predicted based on the model that males would have higher efficacy. This study will be very useful in broadening the perspective of interpreting drug diversity between individuals and narrowing the gap in knowledge related to scientific precision medicine by presenting new information on gender differences in rabeprazole pharmacometrics that had not been previously identified. Full article

Human malnourishment is a current problem of society, and agronomic biofortification is a procedure that wishes to tackle these mineral deficits in human diets by increasing a specific nutrient in the edible part of food crops. Calcium is an important mineral element that performs structural functions and thus can help prevent the development of pathologies such as osteoporosis. Thereby, this work aims to study the impact of calcium enrichment on fatty acid (FA) content in Rocha pears. Thus, an agronomic enrichment workflow with seven foliar sprays of CaCl₂ (with concentrations between 4–8 kg/ha) was performed in an orchard located in the western region of Portugal. Besides Ca enrichment assessment in fruits (with a portable X-ray fluorescence analyzer) at harvest, fatty acids quantification and FA profile (acquired with a gas–liquid chromatograph, coupled to a flame ionization detector (GC-FID)), double bond index (DBI), and lipoperoxidation values (with a spectrophotometer) were also attained. Increases of Ca in sprayed fruits reached 7.6% to 44.3%. For FA-related parameters, no significant differences were observed, suggesting that Ca sprays did not impact these parameters. Total fatty acids (TFA), DBI, and lipoperoxidation values varied between 0.72–0.74 g/100 g FW, 8.13–9.83 and 2.23–3.18 µM/g FW, respectively. The following FA profile was attained: C18:2 > C16:0 > C18:3 > C18:0 > C18:1 > <C16:0. No significant differences were observed. In summary, CaCl₂ can be used to increase Ca levels in fruits, allowing the production of fruits with prophylactic characteristics, while the concentrations from this study did not impact their FA content. Overall, this suggests that cell compartmentation and membranes’ regular functioning were maintained, suggesting the absence of lipid decay and avoiding a potential increase in storage losses. Full article