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To study the influence of tip clearance on the working characteristics of high-altitude fans, this paper takes the MIX-140 high-altitude fan as the research object. Five different tip clearance (TC) models are selected. The CFD method is used to analyze the changes in the working characteristics of the fan under different flow rates and TCs in ground and high-altitude environments. The reliability of the numerical method is verified through a fan test bench. The results show that the tip leakage flow caused by the TC will continuously deteriorate the working characteristics of the fan. Under the rated flow rate in the ground environment, for every doubling of the blade's TC, the static pressure difference will decrease by 5%, the efficiency will decrease by 2%, and the power will decrease by 3%. In a high-altitude environment, the flow rate corresponding to the maximum shaft power point of the fan will continuously increase with an increase in the tip clearance, which will bring about additional energy consumption. For high-altitude fans, the deformation caused by the high-speed rotation of the impeller needs to be taken into account. Undoubtedly, it is advantageous to choose the smallest possible tip clearance value. The results of the analysis and test methods in this paper will provide a basis for designing the tip clearance of high-altitude fans. [ABSTRACT FROM AUTHOR]

To evaluate the efficacy of yellow light-emitting diode (LED) irradiation at 590 nm, alone or in combination with anti-inflammatory active substances against ultraviolet (UV)-induced inflammation in keratinocytes. HaCaT keratinocytes were pretreated with LED yellow light (590 nm) alone or in combination with an antiinflammatory active substance such as glycerophosphoinositol choline (GC), extract of grains of paradise (Aframomum melegueta Schum, AM), or a bisabolol and ginger root extract mixture (Bb-GE) before UVB irradiation. Following each treatment, we measured the levels of inflammatory mediators secreted by keratinocytes. HaCaT keratinocytes treated with UVB (300 mJ cm−²) and then cultured for 24 h exhibited significantly upregulated expression of proinflammatory factors, including interleukin (IL)-1α, prostaglandin E2 (PGE2), and IL-8. After pretreatment with 590 nm LED, UVB-induced inflammatory responses were significantly inhibited. Co-pretreatment with 590 nm LED irradiation and GC further inhibited the expression of IL-1α and IL-8. IL-8 expression was inhibited by co-pretreatment with 590 nm LED irradiation and AM, whereas PGE2 expression was inhibited by co-pretreatment with 590 nm LED irradiation and Bb-GE. Co-treatment with 590 nm LED irradiation and various active substances modulated UVB-induced inflammation in keratinocytes, suggesting the potential application of this approach to prevent damage caused by voluntary sun exposure in daily life. [ABSTRACT FROM AUTHOR]

Piezocatalysis offers a facile method for H2O2 production with the ability to obtain the desired product under clean and safe conditions. In this study, an efficient ternary n-n type van der Waals (vdW) heterojunction piezocatalyst Bi/Bi4Ti3O12/g-C3N4 (BBC) was fabricated by a facile hydrothermal method, leading to the in situ reduction of metallic Bi and the formation of a heterojunction. The piezocatalytic activity of the BBC nanocomposite for H2O2 production (10.5 mmol g–1 h–1) is significantly enhanced by the synergistic effect of metallic Bi and g-C3N4, exceeding that of pure BTO and g-C3N4 by factors of 2.19 and 1.98, respectively. The piezoelectric catalytic mechanism demonstrates that the boosted piezocatalytic performance of this novel nanocomposite BBC could be attributed to the unique structure and the strengthened internal electric fields formed by the vdW heterojunction that improved the charge separation efficiency. This work presents an effective strategy to fabricate efficient nanocomposites capable of converting mechanical energy into chemical energy. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (Li−S) have possessed gratifying development in the past decade due to their high theoretical energy density. However, the severe polysulfide shuttling provokes undesirable self‐discharge effect, leading to low energy efficiency in Li−S batteries. Herein, an interlayer composed of oxygen‐rich carbon nanosheets (OCN) derived from bagasse is elaborated to suppress the shuttle effect and reduce the resultant self‐discharge effect. The OCN interlayer is able to physically block the shuttling behavior of polysulfides and its oxygen‐rich functional groups can strongly interact with polysulfides via O−S bonds to chemically immobilize mobile polysulfides. The self‐discharge test for seven days further shows that the self‐discahrge rate is diminished by impressive 93 %. As a result, Li−S batteries with the OCN interlayer achieve an ultrahigh discharge specific capacity of 710 mAh g−1 at a high mass loading of 7.18 mg. The work provides a facile method for designing functional interlayers and opens a new avenue for realizing Li−S batteries with high energy efficiency. [ABSTRACT FROM AUTHOR]

Intelligent perception technology is an advanced bionic technology that simulates human sensory organs using sensor technology to capture various sensory attributes of samples. By combining intelligent recognition algorithms and signal processing, it enables the comprehensive anthropomorphic evaluation of sample quality. As a modern extension and supplement to traditional sensory evaluation techniques, intelligent perception technology offers technical characteristics such as fast detection speed, no sample pretreatment, easy operation, and real-time online analysis, etc. It serves as a powerful tool for in-depth perception of sensory quality in food. This paper provides an overview of several key intelligent perception technologies in food industry, including electronic tongue technology for simulating taste, electronic nose technology for simulating smell, texture analyzers for simulating touch, and electronic vision systems for simulating sight. Additionally, the article summarizes the application and research progress of intelligent perception technology in food quality evaluation, while also discussing the potential development possibilities of intelligent sensing technology in static sensory, dynamic sensory, and emotional perception representation. With rapid advancements in interdisciplinary fields such as biology, materials science, and computer science, intelligent perception technology is expected to evolve from distinguishing and identifying the overall sensory characteristics of samples to detecting and representing food preferences and emotions, thereby providing new impetus for the development of the food industry. [ABSTRACT FROM AUTHOR]

A fan is part of the core equipment of a super-pressure balloon altitude control system, and high-performance fans have a significant impact on the altitude control capability and flight safety of super-pressure balloons. This paper proposes a mixed-flow MIX-140 fan for use with super-pressure balloons. Changes in the fan's operating characteristics at various flight altitudes of a super-pressure balloon were investigated. First, the performance of the fan at ground level was obtained through numerical simulation and compared with measured data of the prototype to verify the accuracy of the simulation analysis. On this basis, the influences of changes in the atmospheric pressure, temperature, and fan speed on fan performance were investigated through numerical simulation. Furthermore, the MIX-140 fan was compared with an existing fan, and the variation of two parameters, namely, the ratio of inflation volume per unit time and the ratio of inflation volume per unit power, were investigated at different altitudes. Finally, the changes in the operating characteristics of the fan under different high-altitude environments were investigated through actual testing. The results reveal that changes in altitude can lead to significant changes in fan performance, and changes in the atmospheric pressure, temperature, and fan speed affect the fan's working characteristics. Compared with the existing fan, the MIX-140 fan achieves an average increase of 295.8% in the inflation volume per unit of time, and 14.6% in the inflation volume per unit of power at altitudes of 16–20 km. The performance variation characteristics and testing methods of this proposed super-pressure balloon fan can provide a foundation and reference for the design of a super-pressure balloon control system. [ABSTRACT FROM AUTHOR]

Almost all commercial bioprosthetic heart valves (BHVs) are crosslinked with glutaraldehyde (GLUT); however, issues such as immune responses, calcification, delayed endothelialization, and especially severe thrombosis threaten the service lifespan of BHVs. Surface modification is expected to impart GLUT-crosslinked BHVs with versatility to optimize service performance. Here, a postfunctionalization strategy was established for GLUT-crosslinked BHVs, which were firstly modified with metal-phenolic networks (MPNs) to shield the exposed calcification site, and then anticoagulant recombinant humanized type III collagen (rhCOLIII) was immobilized to endow them with long-term antithrombogenicity and enhanced endothelialization properties. The postfunctionalization coating exhibited promising mechanical properties and resistance to enzymatic degradation capability resembling that of GLUT-crosslinked porcine pericardium (GLUT-PP). With the introduction of meticulously tailored rhCOLIII, the anti-coagulation and re-endothelialization properties of TA/Fe-rhCOLIII were significantly improved. Furthermore, the mild inflammatory response and reduced calcification were evidenced in TA/Fe-rhCOLIII by subcutaneous implantation. In conclusion, the efficacy of the proposed strategy combining anti-inflammatory MPNs and multifunctional rhCOLIII to improve anticoagulation, reduce the inflammatory response, and ultimately achieve rapid reendothelialization was supported by both ex vivo and in vivo experiments. Altogether, the current findings may provide a simple strategy for enhancing the service function of BHVs after implantation and show great potential in clinical applications. [ABSTRACT FROM AUTHOR]

Hereditary spherocytosis (HS) is a common, hereditary hemolytic anemia (HHA) that is attributed to the disturbance of five erythrocyte membrane proteins. HS is also common in Guangxi, China. Target region capture high-throughput sequencing technology was used to analyze genetic mutations found in HS patients. Pedigree analysis was also performed, in some cases, to provide an optimized approach for the etiological diagnosis of complex, hereditary hemolytic anemia. Blood samples from the probands and their families were assessed by laboratory tests, target region capture high-throughput sequencing technology, and Sanger sequencing. We detected 79 HS patients from 37 unrelated families. The mutations observed in these patients were found mainly in four HS-related genes. These included SLC4A1, which was mutated in 31.65% of patients (25/79), SPTA1 (30.78% (24/79)), EPB42 (6.33% (5/79)), and SPTB (5.06% (4/79)). Composite genotype was observed in 26.58% (21/79) of patients and included mutations in two or more HS-related genes or mutations in HS-related genes combined with thalassemia or G6PD deficiency. No significant differences in clinical symptoms were found among patients of various genotypes except total bilirubin. Mean reticulocyte volume (MRV) and mean sphered cell volume (MSCV) of the composite genotype were significantly different from other groups. A total of 28 mutation types were found in HS-related genes. Using high-throughput sequencing technology, we also found some cases that had been misdiagnosed. MRV and MSCV are more significant in compound mutations as sensitive determinants of HS. High-throughput sequencing technology can be used to provide a more effective etiological diagnostic method for HS, with high efficiency and specificity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chlorogenic acid (CGA), as one of the most abundant naturally occurring phenolic acids, has been documented to be beneficial for intestinal health. However, the underlying mechanism is still not fully understood. The adult intestinal stem cell is the critical driver of epithelial homeostasis and regeneration. RESULTS: This study hypothesized that CGA exerted intestinal health effects by modulating intestinal stem‐cell functions. Lgr5‐EGFP mice were treated for 14 days, and intestinal organoids derived from these mice were treated for 3 days, using CGA solution. In comparison with the control group, CGA treatment increased intestinal villous height and crypt depth in mice and augmented the area expansion and the number of budding intestinal organoids. Quantitative polymerase chain reaction (qPCR) analysis revealed that CGA treatment significantly increased the expression of genes coding intestinal stem‐cell markers in intestinal tissue and organoids, and upregulated the expression of genes coding secretory cell lineages and enterocytes, although not statistically significantly. Fluorescence‐activated cell‐sorting analysis further confirmed that CGA augmented the number of stem cells. 5‐Ethynyl‐2'‐deoxyuridine (EdU) incorporation and Ki67 immunostaining results also demonstrated that CGA treatment enhanced intestinal stem‐cell proliferation. CONCLUSION: Altogether, our findings indicate that CGA could activate intestinal stem‐cell and epithelial regeneration, which could contribute to the improvement of intestinal morphology or organoid growth of mice. This highlights a promising mechanism for CGA as an excellent candidate for the formulation of dietary supplements and functional foods for intestinal protection. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies have demonstrated that, in contrast to the properties of food‐derived copper, water‐derived copper exerts neurotoxic effects and exhibits different speciation during digestion. The cellular uptake efficiencies of different speciation of copper are distinct. However, it is unclear whether these different speciation share the same transport pathway in intestinal epithelial cells. In the present study, the intracellular accumulation of copper derived from copper ion and copper complex solutions was investigated in Caco‐2 cells. RESULTS: The cellular accumulation of copper derived from copper ions was higher than that of copper derived from the copper complex. Treatment with carboplatin and Ag+, which are copper transporter receptor 1 (Ctr1, LC31A1) inhibitors, did not inhibit copper accumulation in Caco‐2 cells, but inhibited copper accumulation in HepG2 cells. Zinc ion significantly decreased the intracellular copper content from 114 ± 7 μg g−1 protein to 88 ± 4 μg g−1 protein in the copper ion‐treated Caco‐2 cells, but not in the copper complex‐treated Caco‐2 cells (84.6 ± 14 μg g−1 protein versus 87.7 ± 20 μg g−1 protein, P > 0.05). Additionally, copper accumulation in Caco‐2 and HepG2 cells significantly differed depending on different solvents (Hanks' balanced salt solution and NaNO3, P < 0.05). CONCLUSION: These results indicate that the intracellular accumulation of copper derived from copper ion and copper complex is mediated by distinct copper transport pathways. Copper speciation may be an important factor that affects copper absorption and toxicity. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The oral microbiome is second only to its intestinal counterpart in diversity and abundance, but its effects on taste cells remains largely unexplored. Using single-cell RNASeq, we found that mouse taste cells, in particular, sweet and umami receptor cells that express taste 1 receptor member 3 (Tas1r3), have a gene expression signature reminiscent of Microfold (M) cells, a central player in immune surveillance in the mucosa-associated lymphoid tissue (MALT) such as those in the Peyer's patch and tonsils. Administration of tumor necrosis factor ligand superfamily member 11 (TNFSF11; also known as RANKL), a growth factor required for differentiation of M cells, dramatically increased M cell proliferation and marker gene expression in the taste papillae and in cultured taste organoids from wild-type (WT) mice. Taste papillae and organoids from knockout mice lacking Spib (SpibKO), a RANKL-regulated transcription factor required for M cell development and regeneration on the other hand, failed to respond to RANKL. Taste papillae from SpibKO mice also showed reduced expression of NF-κB signaling pathway components and proinflammatory cytokines and attracted fewer immune cells. However, lipopolysaccharide-induced expression of cytokines was strongly up-regulated in SpibKO mice compared to their WT counterparts. Like M cells, taste cells from WT but not SpibKO mice readily took up fluorescently labeled microbeads, a proxy for microbial transcytosis. The proportion of taste cell subtypes are unaltered in SpibKO mice; however, they displayed increased attraction to sweet and umami taste stimuli. We propose that taste cells are involved in immune surveillance and may tune their taste responses to microbial signaling and infection. [ABSTRACT FROM AUTHOR]

Anti-inflammation and anti-coagulation are the primary requirements for cardiovascular stents and also the widely accepted trajectory for multi-functional modification. In this work, we proposed an extracellular matrix (ECM)-mimetic coating for cardiovascular stents with the amplified functionalization of recombinant humanized collagen type III (rhCOL III), where the biomimetics were driven by structure mimicry and component/function mimicry. Briefly, the structure-mimic was constructed by the formation of a nanofiber (NF) structure via the polymerization of polysiloxane with a further introduction of amine groups as the nanofibrous layer. The fiber network could function as a three-dimensional reservoir to support the amplified immobilization of rhCoL III. The rhCOL III was tailored for anti-coagulant, anti-inflammatory and endothelialization promotion properties, which endows the ECM-mimetic coating with desired surface functionalities. Stent implantation in the abdominal aorta of rabbits was conducted to validate the in vivo re-endothelialization of the ECM-mimetic coating. The mild inflammatory responses, anti-thrombotic property, promotion of endothelialization and suppression of excessive neointimal hyperplasia confirmed that the ECM-mimetic coating provided a promising approach for the modification of vascular implants. [ABSTRACT FROM AUTHOR]

Circadian pace is modulated by light intensity, known as the Aschoff's rule, with largely unrevealed mechanisms. Here we report that photoreceptor CRY2 mediates blue light input to the circadian clock by directly interacting with clock core component PRR9 in blue light dependent manner. This physical interaction dually blocks the accessibility of PRR9 protein to its co-repressor TPL/TPRs and the resulting kinase PPKs. Notably, phosphorylation of PRR9 by PPKs is critical for its DNA binding and repressive activity, hence to ensure proper circadian speed. Given the labile nature of CRY2 in strong blue light, our findings provide a mechanistic explanation for Aschoff's rule in plants, i.e., blue light triggers CRY2 turnover in proportional to its intensity, which accordingly releasing PRR9 to fine tune circadian speed. Our findings not only reveal a network mediating light input into the circadian clock, but also unmask a mechanism by which the Arabidopsis circadian clock senses light intensity. Circadian pace is modulated by light intensity. Here the authors show that CRY2 interacts with PRR9 to mediate blue light input to the circadian clock and is degraded at higher light intensity offering a mechanistic explanation as to how intensity can modify clock place. [ABSTRACT FROM AUTHOR]

The clarity of taste sensation interaction is a key basis for promoting the food sensory science research and its application to the beverage and food additive industries. This study explored the synergy and antagonism effect of sucrose-citric acid mixture and established an optimized method to determine the human sweetness and sourness interactive response. Sucrose-citric acid mixtures were evaluated by the "close type" question. According to the sensory difference strength curves and Weber–Fechner law, citric acid increased the sucrose's absolute threshold (0.424–0.624%) and weber fraction (20.5–33.0%). Meanwhile, sucrose increased citric acid's absolute threshold (0.0057–0.0082%) and decreased its weber fraction (17.96–9.53%). By fitting absolute threshold and weber fraction variation equations, the sweet–sour taste sensory strength variation models (SSTVM) were derived, which could be used to explain the synergy and antagonism effect of sweet–sour taste. According to the SSTVM, the interactive response to sweet–sour taste could be quantitatively calculated. The high coincidence between SSTVM and human evaluation (1.02% of relative error) indicated that it could be applied in the food industry, health management, and intelligent sensory science. [ABSTRACT FROM AUTHOR]

Intestinal tract is the major organ for digestion and absorption of food nutrients. The establishment of an effective intestinal ex vivo model is helpful to promote the development of a novel evaluation system for absorption and efficacy of food nutrients and functional active substances. Based on the intestinal crypt containing intestinal stem cells, we created an integrated set of organoid culture of different intestinal segments (including duodenum, jejunum and ileum) of mouse through optimizing the isolation method of intestinal crypt from different intestinal segment and the composition of culture medium. In addition, RT-PCR and immunofluorescence results demonstrated that the organoids derived from different segment recapitulate the structural characteristics and cell composition of corresponding intestinal tissues. These characters had high stability during in vitro repeated passage. In short, the establishment of orgnaoid culture of different intestinal segment may provide a promising ex vivo model for the evaluation of absorption and function of food nutrients in the food research field. [ABSTRACT FROM AUTHOR]

Taste perception, initiated by activation of taste receptors in taste bud cells, is crucial for regulating nutrient intake. Genetic polymorphisms in taste receptor genes cannot fully explain the wide individual variations of taste sensitivity. Alternative splicing (AS) is a ubiquitous posttranscriptional mode of gene regulation that enriches the functional diversity of proteins. Here, we report the identification of a novel splicing variant of sweet taste receptor gene Tas1r2 (Tas1r2_∆e4) in mouse taste buds and the mechanism by which it diminishes sweet taste responses in vitro and in vivo. Skipping of Tas1r2 exon 4 in Tas1r2_∆e4 led to loss of amino acids in the extracellular Venus flytrap domain, and the truncated isoform reduced the response of sweet taste receptors (STRs) to all sweet compounds tested by generating nonfunctional T1R2/T1R3 STR heterodimers. The splicing factor PTBP1 (polypyrimidine tract-binding protein 1) promoted Tas1r2_∆e4 generation through binding to a polypyrimidine-rich splicing silencer in Tas1r2 exon 4, thus decreasing STR function and sweet taste perception in mice. Taken together, these data reveal the existence of a regulated AS event in Tas1r2 expression and its effect on sweet taste perception, providing a novel mechanism for modulating taste sensitivity at the posttranscriptional level. [ABSTRACT FROM AUTHOR]

4‐(2‐Chlorobenzyl)‐1‐(furan‐2‐yl)‐[1,2,4]triazolo[4,3‐a]quinazolin‐5(4H)‐one is a triazoloquinazolinone compound with broad‐spectrum biological activity. In this study, the four‐step method was used to synthesize the title compound, and its structure was confirmed by Fourier‐transform infrared spectroscopy (FT‐IR), proton nuclear magnetic resonance (1H NMR), 13‐carbon nuclear magnetic resonance (13C NMR) spectroscopy, and mass spectroscopy (MS). Further, its single crystal was characterized by X‐ray diffraction. The density functional theory was used to calculate the optimal structure of the molecule. The results demonstrated that the analyzed structure was consistent with the crystal structure determined by single‐crystal diffraction. In addition, discrete Fourier transform was used to study the molecular electrostatic potential and Frontier molecular orbital of the title compound, revealing a few of the compound's physicochemical properties. [ABSTRACT FROM AUTHOR]

A novel series of triazoloquinazolinone derivatives were designed, synthesised, and evaluated for their in vitro biological activities against the SHP2 protein. Moreover, some compounds were evaluated against A375 cells. The results revealed that target compounds possessed moderate to excellent inhibitory activity against SHP2 protein, whereas compounds 12f, 12l, 12j, 17e, and 17f have strong antiproliferative activity on A375 cells. The compound 12l showed remarkable cytotoxicity against A375 cells and a strong inhibitory effect against SHP2 protein when compared with SHP244. The structure-activity relationships (SARs) indicated that electron-donating groups (EDGs) on phenyl rings are beneficial for improving the antitumor activity; compounds with a hydroxyl substituent at the 2-position of phenyl ring exhibited superior activities than compounds with a substituent at the 4-position. In addition, compound 12l displayed improved physicochemical properties as well as metabolic stability compared to SHP244. Our efforts identified 12l as a promising SHP2 protein inhibitor, warranting its further investigation. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of chronic administration of caffeine on the anatomical characteristics of taste buds, the expression level of taste receptor protein in mice, and preference for a palatable solution. We found that following a 21-day administration of caffeine, mice showed increased behavioural responses to sweet stimuli (acesulfame-K solution). Mirroring this behavioural change, chronic caffeine treatment evidently decreased the maximal cross-sectional area and height of the longitudinal axis of fungiform taste buds, the number of taste cells per fungiform taste bud, and the expression of G protein α-gustducin, while the expression of the sweet taste receptors T1R2 and T1R3 was reversed. Our findings demonstrate that chronic administration of caffeine has an impact on taste sensitivity and changes in taste bud features, which may contribute to the alteration of taste behaviour. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sour taste perception builds on both chemical and physiological foundations, and plays an important role in food flavor, including that of fruit, beer, wine, and other beverages. A uniform sourness standard and sourness conversion method for researchers and food enterprises is necessary to obtain uniform conclusions. RESULTS: This study established an optimized organic acid sensory sourness analysis and sourness conversion method. It is based on sour sensory difference strength curves, which consist of an absolute threshold value and sensory difference threshold values. Defining the absolute threshold value of citric acid sourness as 1, sourness could be calculated according to the curve. With a logarithmic curve form, the acid sourness indexes (AI) were calculated as 1, 0.74, 0.77, 1.31, and 1.21 for citric, malic, fumaric, lactic, and tartaric acid samples, respectively. Consequently, each acid's sourness and concentration could be obtained and converted. Single acid and mixed acid sourness comparison evaluation's result implied that the novel method was more accurate (91.7–100%) than the hydrogen ion concentration method. CONCLUSION: The novel sourness determination and conversion equation would provide more accurate sourness standard and calculation method in food sensory areas. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Speciation can provide knowledge about absorption, reactivity to binding sites, bioavailability, toxicity, and excretion of elements. In this study, the speciation of copper in different model solutions under the influence of gastrointestinal (GI) pH was studied by ion selective electrode (ISE) and inductively coupled plasma optical emission spectrometry (ICP OES). It was found that the electrode response (mV) against Cu2+ decreased with the increase in pH and dropped to the lowest point at pH 7.5 in all model solutions. When amino acids and organic acids were present, the ratio of filtered copper (0.45 μm, pH 7.5) was more than 90%. When casein was present, whey protein, pancreatin, and starch were added, and the ratio of filtered copper was 85.6 ± 0.3, 56.7 ± 8.8, 38.5 ± 5.1, and 1.0 ± 0.3%, respectively. When there is not enough organic ligand, excessive copper will form copper hydroxide precipitation with the increase in pH, but it got the highest electrode response (mV) against Cu2+. From this study, it can be concluded that the speciation of copper in GI tract is strongly influenced by the pH and the composition of food. When there are few ligands coexisting in the GI tract, the concentration of copper ion may be relatively high. [ABSTRACT FROM AUTHOR]

Sunset yellow (SY), an azo dye, is commonly used in the food industry. The scientific literature contains little information regarding the effects of SY on small intestinal epithelial cells (IECs). In this study, a small intestinal organoid model was used in in vitro toxicological studies of SY, and intestinal inflammatory responses in vivo to SY were investigated with the dextran sulfate sodium (DSS)‐induced intestinal inflammation model in C57BL/6 mice. The intestinal organoids were cultured with 2 μg/ml SY for two generations, the growth rates were analyzed, and the expressions of cell lineages were assayed. For inflammatory responses, mice were fed with a diet containing 40 mg/kg diet SY and treated with 2.5% DSS for 7 days. The results showed that SY inhibited the growth of the organoids by inhibiting the proliferation and disturbing the differentiation of IECs. Furthermore, endoplasmic reticulum (ER) stress and oxidative stress levels were elevated in SY‐treated organoids. In DSS‐treated mice, the disease activity index and expression levels of interleukin‐1β and tumor necrosis factor‐α were enhanced in the SY group, concluding that SY exacerbated DSS‐induced intestinal inflammation. Taken together, these findings revealed that SY could disturb the homeostasis of the small intestinal epithelium by generating high levels of ER stress and oxidative stress, with long‐term continuous consumption of SY potentially increasing the risk of intestinal inflammation. Little is known about the toxicological effects of sunset yellow (SY) on small intestine. The present study investigated the impacts of SY on growth of intestinal cells in small intestinal organoids and DSS‐induced intestinal inflammation model. The results revealed that SY disturbed the homeostasis of small intestinal epithelium via inhibiting the proliferation and altering the differentiation of small intestinal cells, which might result from the elevated ER stress and oxidative stress. Long‐term continuous consumption of SY could increase the risk of intestinal inflammation. [ABSTRACT FROM AUTHOR]

Aging is an important factor affecting function of smell, leading to the degeneration of mature olfactory sensory neurons and inducing the occurrence of smell loss. The mammalian olfactory epithelium (OE) can regenerate when subjected to chemical assaults. However, this capacity is not limitless. Inactivation of globose basal cells and failure to generate sensory neurons are the main obstacles to prevent the OE regeneration. Here, we found the significant attenuation in mature sensory neuronal generation and apparent transcriptional alternation in the OE from aged mice compared with young ones. The recruitment of leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5)-positive cells in injured OE was weakened in aged mice, and more Lgr5+ cells remained quiescence in aged OE postinjury. Lineage-traced progenies from Lgr5+ cells were significantly fewer in the OE with aging. Moreover, Notch activation enhanced the neuronal regeneration in aged OE, making the regenerative capacity of aged OE comparable with that of young animals after injury. The growth and morphology of three-dimensional (3D)-cultured organoids from the OE of young and aged mice varied and was modulated by small molecules regulating the Notch signaling pathway. Thus, we concluded that activation of Lgr5+ cells in injured OE was age dependent and Notch activation could enhance the capacity of neuronal generation from Lgr5+ cells in aged OE after injury. [ABSTRACT FROM AUTHOR]

Mouse taste receptor cells survive from 3–24 days, necessitating their regeneration throughout adulthood. In anterior tongue, sonic hedgehog (SHH), released by a subpopulation of basal taste cells, regulates transcription factors Gli2 and Gli3 in stem cells to control taste cell regeneration. Using single-cell RNA-Seq we found that Gli3 is highly expressed in Tas1r3-expressing taste receptor cells and Lgr5+ taste stem cells in posterior tongue. By PCR and immunohistochemistry we found that Gli3 was expressed in taste buds in all taste fields. Conditional knockout mice lacking Gli3 in the posterior tongue (Gli3CKO) had larger taste buds containing more taste cells than did control wild-type (Gli3WT) mice. In comparison to wild-type mice, Gli3CKO mice had more Lgr5+ and Tas1r3+ cells, but fewer type III cells. Similar changes were observed ex vivo in Gli3CKO taste organoids cultured from Lgr5+ taste stem cells. Further, the expression of several taste marker and Gli3 target genes was altered in Gli3CKO mice and/or organoids. Mirroring these changes, Gli3CKO mice had increased lick responses to sweet and umami stimuli, decreased lick responses to bitter and sour taste stimuli, and increased glossopharyngeal taste nerve responses to sweet and bitter compounds. Our results indicate that Gli3 is a suppressor of stem cell proliferation that affects the number and function of mature taste cells, especially Tas1r3+ cells, in adult posterior tongue. Our findings shed light on the role of the Shh pathway in adult taste cell regeneration and may help devise strategies for treating taste distortions from chemotherapy and aging. [ABSTRACT FROM AUTHOR]

The cascade Förster resonance energy transfer (FRET) is a multiple step nonradiative process that occurs between more than one pair of energy donor and acceptor molecules on the scale less than 10 nm, and it has played an important role in developing fluorescence sensors because of its simplicity and sensitivity. Here, blue-emitting neutral poly(vinyl carbazole), green-emitting tris-(8-hydroxy-quinoline) aluminum, tris[2-(4,6-difluorophenyl) pyridinato-C2,N] iridium (III), and orange-emitting 4-(dicyano-methylene)-2-methyl-6-(4-dimethylamino-styryl)-4H-pyran (DCM) are coassembled with layered double hydroxide nanosheets using a layer-by-layer method to form inorganic/organic composite luminescence ultrathin films (UTFs). The UV-vis absorption, scanning electron microscopy, and small-angle X-ray diffraction results demonstrate that the fabricated ultrathin films are ordered, linear growth, and homogeneous. The photoluminescence spectroscopy demonstrates that the 2D cascade FRET process is realized and a significant enhancement of light emission and extended lifetime of DCM dye is obtained in the UTF. Furthermore, these composite UTFs show fast, sensitive, and selective fluorescence signal patterns toward common volatile organic compounds (VOCs) based on interfering the 2D cascade FRET process, implying its potential application in the VOC selective sensing field. [ABSTRACT FROM AUTHOR]

In this work, neutral dye 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) incorporated by a block copolymer micelle (BCM), poly(styrene)-b-acrylic acid (PS-b-PAA), was assembled with layered double hydroxide (LDH) nanosheets to fabricate luminous ultrathin films by the layer-by-layer method. The UV-vis absorption spectra, SEM and AFM characterization results confirmed that composite ultrathin films (UTFs) were homogenous with long-range ordered stacking vertical to the quartz substrate. The UTFs maintained the photoluminescence (PL) properties of DCM with well-defined orange fluorescence, which originate from the locally excited state of DCM without molecule aggregation. Meanwhile, these ultrathin films demonstrated a typical solvatochromism fluorescence feature of DCM molecules, with the PL peak strongly dependent on solvent polarity. The fluorescence of the UTFs can be adjusted from orange to red upon exposure to different volatile organic compound (VOC) vapours, based on the DCM twisted intramolecular charge transfer character excited state. These DCM-loaded UTFs showed fast, sensitive and reversible fluorescence solvatochromism in response to common VOCs. This work opens up the avenue for potential applications of DCM in the VOC polarity sensors. [ABSTRACT FROM AUTHOR]

Fluorescence sensing of nucleotides is an important topic for biosensor and fluorescence materials. In this paper, a cheap UV light absorber, 2-phenylbenzimidazole-5-sulfonate (PBS) was immobilized into the interlayers of Zn2Al layered double hydroxides (LDHs) by co-intercalating with 1-decane sulfonate (DES) anions. The dependence of fluorescence on the molar concentration (x%) of PBS was investigated, and the PBS(15%)–DES/LDH composite exhibited optimal violet luminescence at 402 nm, compared with that of the PBS solution with luminescence at 342 nm. The PBS(15%)–DES/LDH composite thin films were fabricated by solvent evaporation method on quartz substrate. Moreover, the composite thin film exhibited remarkable PBS luminescence transformation (violet to UV light) for nucleotide triphosphates (ATP, GTP, CTP and UTP), compared with their diphosphate and monophosphate counterparts (ADP, AMP and etc.), which makes it a prospective sensor for the nucleotide molecules at the simulated physiological conditions. The origin of the luminescence enhancement was investigated and attributed to the extensive hydrogen bonding interaction between the intercalated PBS and nucleotides. [ABSTRACT FROM AUTHOR]

Neutral poly(vinyl carbazole) (PVK) and tetraphenylethylene (TPE) molecules were assembled within the interlayers of layered double hydroxide (LDH) nanosheets to form (TPE@PVK/LDH)n ultrathin films (UTFs) by the hydrogen-bonding layer by layer assembly method. These UTFs exhibit well defined blue luminescence of TPE, which implies that the intercalation anchoring of aggregation induced emission (AIE)-type chromophores to the rigid LDH matrix can serve as an alternative mechanism for restricting the rotation of the phenyl rings of TPE. The concentration–fluorescence relationship study implied that the AIE effect of intercalated TPE can be regarded as the 2D restriction-induced photoemission (RIE) effect within the interlayers. Moreover, the 2D Förster/fluorescence resonance energy transfer (FRET) process between PVK and TPE was realized within these UTFs, by which the UTFs exhibit reversible two-state switching of fluorescence emission (violet vs. blue) with the free/restriction states of TPE triggered by the external stimuli (e.g. volatile organic compound (VOC) vapors). Therefore, this 2D assembly of UTFs worked not only as the 2D RIE environment for TPE molecules, but also as a FRET 2D protocol for fluorescence sensing applications. [ABSTRACT FROM AUTHOR]

On page 6752, J. Lu and co‐workers present a sensor that is selective for volatile organic compounds (VOCs). Based on an inorganic/organic composite ultrathin film, the sensor applies 2D cascade Förster resonance energy transfer (FRET) as readout. PVK@Ir(F2ppy)3@ 4‐(dicyanomethylene)‐2‐methyl‐6‐(4‐dimethylaminostyryl)‐4H‐pyran (DCM) and layered double hydroxide (LDH)nanosheets are assembled by the layer‐by‐layer method. These films show sensitive and selective fluorescence signal patterns for four VOC vapors by modulating the respective FRET process. [ABSTRACT FROM AUTHOR]

In this paper, the inexpensive 4,4-diaminostilbene-2,2-disulfonate (DAS) and 4,4-dinitro-stilbene-2,2- disulfonate (DNS) anions with arbitrary molar ratios were successfully co-intercalated into Zn2Al-layered double hydroxides (LDHs). The DAS(50%)-DNS/LDHs composite exhibited the broad UV-visible light absorption and fluorescence quenching, which was a direct indication of photo-induced electron transfer (PET) process between the intercalated DAS (donor) and DNS (acceptor) anions. This was confirmed by the matched HOMO/LUMO energy levels alignment of the intercalated DAS and DNS anions, which was also compatible for water splitting. The DAS(50%)-DNS/LDHs composite was fabricated as the photoanode and Pt as the cathode. Under the UV-visible light illumination, the enhanced photo-generated current (4.67 mA/cm2 at 0.8 V vs. SCE) was generated in the external circuit, and the photoelectrochemical water split was realized. Furthermore, this photoelectrochemical water splitting performance had excellent crystalline, electrochemical and optical stability. Therefore, this novel inorganic/organic hybrid photoanode exhibited potential application prospect in photoelectrochemical water splitting. [ABSTRACT FROM AUTHOR]