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Clusterin gene transcription is activated by caudal-related homeobox genes in intestinal epithelium. Am J Physiol Gastrointest Liver Physiol 280: G149-G156, 2001.--Caudal-related homeobox (Cdx) proteins play an important role in development and differentiation of the intestinal epithelium. Using cDNA differential display, we identified clusterin as a prominently induced gene in a Cdx2-regulated cellular model of intestinal differentiation. Transfection experiments and DNA-protein interaction assays showed that clusterin is an immediate downstream target gene for Cdx proteins. The distribution of clusterin protein in the intestine was assessed during development and in the adult epithelium using immunohistochemistry. In the adult mouse epithelium, clusterin protein was localized in both crypt and villus compartments but not in interstitial cells of the intestinal mucosa. Together, these data suggest that clusterin is a direct target gene for Cdx homeobox proteins, and the pattern of clusterin protein expression suggests that it is associated with the differentiated state in the intestinal epithelium. Cdx2; differential display; differentiation; transactivation; Caco-2

Estrogen receptors (ER), namely ERα and ERβ, are hormone- activated transcription factors with an important role in carcinogenesis. In the present study, we aimed at elucidating the implication of ERα in skin cancer, using chemically-induced mouse skin turnouts, as well as cell lines representing distinct stages of mouse skin oncogenesis. First, using immunohistochemical staining we showed that ERα is markedly increased in aggressive mouse skin tumours in vivo as compared to the papilloma tumours, whereas ERβ levels are low and become even lower in the aggressive spindle tumours of carcinogen-treated mice. Then, using the multistage mouse skin carcinogenesis model, we showed that ERα gradually increases during promotion and progression stages of mouse skin carcinogenesis, peaking at the most aggressive stage, whereas ERβ levels only slightly change throughout skin carcinogenesis. Stable transfection of the aggressive, spindle CarB cells with a dominant negative form of ERα (dnERα) resulted in reduced ERα levels and reduced binding to estrogen responsive elements (ERE)- containing sequences. We characterized two highly conserved EREs on the mouse ERα promoter through which dnERα decreased endogenous ERα levels. The dnERα-transfected CarB cells presented altered protein levels of cytoskeletal and cell adhesion molecules, slower growth rate and impaired anchorage-independent growth in vitro, whereas they gave smaller turnouts with extended latency period of turnout onset in vivo. Our findings suggest an implication of ERα in the aggressiveness of spindle mouse skin cancer cells, possibly through regulation of genes affecting cell shape and adhesion, and they also provide hints for the effective targeting of spindle cancer cells by dnERα. [ABSTRACT FROM AUTHOR]

In this study, 1 M sodium perchlorate (NaClO 4) containing binary electrolytes based on propylene carbonate and X (X = dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dipropyl carbonate, ethylene carbonate, 1,2-butylene carbonate, monoglyme, diglyme, tetraglyme, sulfolane) are studied due to their electrochemical and physicochemical properties as well as compatibility with sodium metal. The reactivity towards sodium is compared between mixtures with and without NaClO 4 and degradation products are analyzed by gas chromatography. It is shown that NaClO 4 plays a crucial role in electrolyte decomposition and gas formation. It could be shown that mixtures of linear and cyclic carbonates form coupling products during storage with Na metal, namely dialkane propane-1,2-diyl dicarbonates, independently of the presence of sodium perchlorate. Additionally, gas analysis of PC electrolyte over Na shows a pronounced formation of CO and propylene oxide during storage if NaClO 4 is present in the sample. Overall, the electrolyte "PC+EC+NaClO 4 " is identified as most favorable system within the examined series with respect to decomposition characteristics (formation of decomposition products) as well as acceptable physicochemical and electrochemical properties, e.g. plating-stripping behavior, cycle tests, conductivity and solubility. A sustainability screening of the electrolyte formulations reveals a high toxic concern in case of glyme-based mixtures as well as sulfolane. From a life cycle perspective, however, glyme-based mixtures have in overall lower environmental footprints. [ABSTRACT FROM AUTHOR]

In the pursuit of enhancing the fire safety of polyamide 6 (PA6), the addition of flame retardants generally leads to hydrogen bond dissociation, which results in detrimental effects on the mechanical properties of PA6 composites and impedes processing and application in the textile field. In this study, a macromolecular flame retardant, PPB, designed with hydrogen bond donor-acceptor spacing aligned with PA6, was synthesized to increase the number of hydrogen bonds. The addition of 10 wt% PPB to the PA6 matrix (PA6/PPB10) endowed the composite with the limiting oxygen index (LOI) increased to 31.6 % and V-0 rating in the vertical burning (UL-94) test. PA6/PPB10 also exhibited significant enhancement in tensile strength by 12.6 % compared to pure PA6 and demonstrated a superior ultraviolet protection factor (UPF) value of 573, greatly exceeding the value of 3 for PA6. The quenching effect, diluting effect in the gas phase, and hydrogen bond interactions between PPB and PA6 backbones imparted PA6/PPB composites with satisfactory flame retardancy and mechanical properties. As a representative example, PA6/PPB10 was melt-spun into filaments with a pleasing tenacity of 3.6 cN/dtex and self-extinguishing capability within 5 s after ignition, confirming the sustained comprehensive properties after spinning and drawing into filaments. [Display omitted] • A flame retardant (PPB) with hydrogen bond spacing aligned with PA6 was synthesized. • PA6/PPB10 (containing 10 wt% PPB) achieved a LOI of 31.6 % and an UL94 V-0 rating. • PA6/PPB10 presented an increase of 12.6 % in the tensile strength compared to PA6. • PA6/PPB10 had an UPF value of 573, significantly exceeding the value of 3 for PA6. • PA6/PPB10 filaments presented both enhanced flame retardancy and high tenacity. [ABSTRACT FROM AUTHOR]

• A novel strategy for constructing an efficient "all in one" macromolecular intumescent flame retardant (SPPO) was proposed and confirmed. • The serious melt-dripping of PET was completely suppressed only when 6 wt% of SPPO was added. • The PET/SPPO composites exhibit excellent heat, smoke and toxic gas suppression behavior. To improve the flame retardancy of poly(ethylene terephthalate) (PET) without loss of its mechanical properties, a macromolecular intumescent flame retardant (SPPO) with thermal-responsive groups was developed in an effective way. As 8 wt% of SPPO was melt-blended into PET, the prepared PET/SPPO composite achieved a V-0 rating during UL-94 tests without melt-dripping, and exhibited substantial reduction in the total heat release (THR), peak heat release rate (PHRR), total smoke production (TSP) and average carbon monoxide yield (av-COY) by 44.8 %, 39.0 %, 63.3 % and 45.8 %, respectively, in comparison with pure PET. The improved flame retardancy of this composite was considered to be ascribed to the formation of intumescent residues of SPPO. The generated physical barrier increased the melt viscosity by triggering the cross-linking reactions of the C≡N groups in SPPO, effectively inhibiting the melt-dripping of PET during burning. The tensile strength was also well-retained for PET composites when different contents of SPPO were added into PET, demonstrating the good compatibility between SPPO and PET matrix, which can meet the requirements of industrial application. [ABSTRACT FROM AUTHOR]

Cholinergic urticaria is a dermatological disease characterized by the presence of large patches of red skin and transient hives triggered by factors, such as exercise, sweating, and psychological tension. This skin problem is hypothesized to be attributed to a reduced expression of acetylcholinesterase (AChE), an enzyme responsible for hydrolyzing acetylcholine (ACh). Consequently, ACh is thought to the leak from sympathetic nerves to skin epidermis. The redundant ACh stimulates the mast cells to release histamine, triggering immune responses in skin. Here, the exposure of ultraviolet B in skin suppressed the expression of AChE in keratinocytes, both in in vivo and in vitro models. The decrease of the enzyme was resulted from a declined transcription of ACHE gene mediated by micro‐RNAs, that is, miR‐132 and miR‐212. The levels of miR‐132 and miR‐212 were markedly induced by exposure to ultraviolet B, which subsequently suppressed the transcriptional rate of ACHE. In the presence of low level of AChE, the overflow ACh caused the pro‐inflammatory responses in skin epidermis, including increased secretion of cytokines and COX‐2. These findings suggest that ultraviolet B exposure is one of the factors contributing to cholinergic urticaria in skin. [ABSTRACT FROM AUTHOR]

Xiao Cheng Qi (XCQ) decoction, an ancient Chinese herbal mixture, has been used in treating slow-transit constipation (STC) for years. The underlying action mechanism in relieving the clinical symptoms is unclear. Several lines of evidence point to a strong link between constipation and gut microbiota. Short-chain fatty acids (SCFAs) and microbial metabolites have been shown to affect 5-HT synthesis by activating the GPR43 receptor localized on intestinal enterochromaffin cells, since 5-HT receptors are known to influence colonic peristalsis. The objective of this study was to evaluate the efficacy of XCQ in alleviating clinical symptoms in a mouse model of STC induced by loperamide. The application of loperamide leads to a decrease in intestinal transport and fecal water, which is used to establish the animal model of STC. In addition, the relationship between constipation and gut microbiota was determined. The herbal materials, composed of Rhei Radix et Rhizoma (Rhizomes of Rheum palmatum L., Polygonaceae) 55.2 g, Magnoliae Officinalis Cortex (Barks of Magnolia officinalis Rehd. et Wils, Magnoliaceae) 27.6 g, and Aurantii Fructus Immaturus (Fruitlet of Citrus aurantium L., Rutaceae) 36.0 g, were extracted with water to prepare the XCQ decoction. The constipated mice were induced with loperamide (10 mg/kg/day), and then treated with an oral dose of XCQ herbal extract (2.0, 4.0, and 8.0 g/kg/day) two times a day. Mosapride was administered as a positive drug. In loperamide-induced STC mice, the therapeutic parameters of XCQ-treated mice were determined, i.e., (i) symptoms of constipation, composition of gut microbiota, and amount of short-chain fatty acids in feces; (ii) plasma level of 5-HT; and (iii) expressions of the GPR43 and 5-HT4 receptor in colon. XCQ ameliorated the constipation symptoms of loperamide-induced STC mice. In gut microbiota, the treatment of XCQ in STC mice increased the relative abundances of Lactobacillus, Prevotellaceae_UCG_001, Prevotellaceae_NK3B31_group, Muribaculaceae, and Roseburia in feces and decreased the relative abundances of Desulfovibrio, Tuzzerella, and Lachnospiraceae_ NK4A136_group. The levels of SCFAs in stools from the STC group were significantly lower than those the control group, and were greatly elevated via treatment with XCQ. Compared with the STC group, XCQ increased the plasma level of 5-HT and the colonic expressions of the GPR43 and 5-HT4 receptor, significantly. The underlying mechanism of XCQ in anti-constipation could be related to the modulation of gut microbiota, the increase in SCFAs, the increase in plasma 5-HT, and the colonic expressions of the GPR43 and 5-HT4 receptor. Our results indicate that XCQ is a potent natural product that could be a therapeutic strategy for constipation. [ABSTRACT FROM AUTHOR]

Rhizosphere microbes play critical roles for plant's growth and health. Among them, the beneficial rhizobacteria have the potential to be developed as the biofertilizer or bioinoculants for sustaining the agricultural development. The efficient rhizosphere colonization of these rhizobacteria is a prerequisite for exerting their plant beneficial functions, but the colonizing process and underlying mechanisms have not been thoroughly reviewed, especially for the nonsymbiotic beneficial rhizobacteria. This review systematically analyzed the root colonizing process of the nonsymbiotic rhizobacteria and compared it with that of the symbiotic and pathogenic bacteria. This review also highlighted the approaches to improve the root colonization efficiency and proposed to study the rhizobacterial colonization from a holistic perspective of the rhizosphere microbiome under more natural conditions. [ABSTRACT FROM AUTHOR]

The semiconducting properties and applications of three dimensional (3D) covalent organic frameworks (COFs) are greatly hampered because of their long‐ranged non‐conjugated skeletons and relatively unstable linkages. Here, a robust imidazole‐linked fully conjugated 3D covalent organic framework (BUCT‐COF‐7) is synthesized through the one‐pot multicomponent Debus‐Radziszewski reaction of the saddle‐shaped aldehyde‐substituted cyclooctatetrathiophene, pyrene‐4,5,9,10‐tetraone, and ammonium acetate. The semiconducting BUCT‐COF‐7, as a metal‐free catalyst, shows excellent two electron oxygen reduction reaction (ORR) activity in alkaline medium with high hydrogen peroxide (H2O2) selectivity of 83.4 %. When the BUCT‐COF‐7 as cathode catalyst is assembled into the electrolyzer, the devices showed high electrochemical production rate of H2O2 up to 326.9 mmol g−1 h−1. The accumulative amount of H2O2 could totally degrade the dye methylene blue via Fenton reaction for wastewater treatment. This is the first report about intrinsic 3D COFs for efficient electrochemical synthesis of H2O2, revealing the promising applications of fully conjugated 3D COFs in the environment‐related field. [ABSTRACT FROM AUTHOR]

Abstract Obesity is caused by energy imbalance and accompanied by adipocyte hypertrophy and hyperplasia. Therefore, both enhancement of adipocyte energy expenditure and inhibition of adipogenesis are viable ways to combat obesity. Using the Ucp1 -2A-luciferase reporter animal model previously reported by us as a screening platform, a chemical compound Linifanib was identified as a potent inducer of UCP1 expression in primary inguinal adipocytes in vitro and in vivo. Signal pathway analyses showed that Linifanib promoted adipocyte browning by attenuating STAT3 phosphorylation. The effects of Linifanib on adipocyte browning were blocked by the compound, SD19, which activates the STAT3 signaling cascade. Linifanib also inhibited adipocyte differentiation, by blocking mitotic clonal expansion, which could be rescued by STAT3 activator. Taken together, our results indicate that Linifanib might serve as a potential drug for the treatment of obesity. [ABSTRACT FROM AUTHOR]

• Proposal of a novel friction-strip coupled damper. • Low-cycle fatigue tests on eight FSCD specimens including four parameters. • Numerical analyses on distinctive hysteretic behaviors of two modules of the FSCD. Aiming at solving the issue of conventional metallic and friction dampers, this paper proposes a novel friction-strip coupled damper (FSCD) by setting friction and strip modules in parallel. The coupled working mechanism endows the damper to provide sufficient energy dissipation along with stiffness for main structures. Quasi-static tests were conducted on eight FSCD specimens to investigate the effect of the friction force, the strip number, the strip width and the strip configuration on the hysteretic behavior of the FSCD. The test results verified the effectiveness of the three-stage working mechanism, i.e., the collaborative stage, degradation stage and friction-only stage, and demonstrated that the strength, energy dissipation and stiffness of the FSCD increased with the friction force, the strip width and the strip number. The strip with a larger chamfer radius brought no improvement in the seismic performance of the FSCD, whereas the FSCD with strips adopting a modified elliptic-arc edge presented higher strength, better energy dissipation capacity and stiffness. Moreover, a detailed numerical model considering the ductile damage behavior was established and validated. The numerical result matched well with the test one in terms of the hysteretic performance, energy dissipation and stiffness of the FSCD. Besides, the gradual fracture of strips was also clearly captured by the finite element model. [ABSTRACT FROM AUTHOR]

Species of the genus Bacillus have been widely used for the biocontrol of plant diseases in the demand for sustainable agricultural development. New mechanisms underlying Bacillus biocontrol activity have been revealed with the development of microbiome and microbe-plant interaction research. In this review, we first briefly introduce the typical Bacillus biocontrol mechanisms, such as the production of antimicrobial compounds, competition for niches/nutrients, and induction of systemic resistance. Then, we discussed in detail the new mechanisms of pathogen quorum sensing interference and reshaping of the soil microbiota. The "cry for help" mechanism was also introduced, in which plants can release specific signals under pathogen attack to recruit biocontrol Bacillus for root colonization against invasion. Finally, two emerging strategies for enhancing the biocontrol efficacy of Bacillus agents, including the construction of synthetic microbial consortia and the application of rhizosphere-derived prebiotics, were proposed., (© 2023 The Authors. Microbial Biotechnology published by Applied Microbiology International and John Wiley & Sons Ltd.)

The methylation of lysine 4 of histone H3 (H3K4), catalyzed by the histone methyltransferase KMT2/SET1, has been functionally identified in many pathogenic fungi but remains unexplored in nematode-trapping fungi (NTFs). Here, we report a regulatory mechanism of an H3K4-specific SET1 orthologue, AoSET1, in the typical nematode-trapping fungus Arthrobotrys oligospora. When the fungus is induced by the nematode, the expression of AoSET1 is up-regulated. Disruption of AoSet1 led to the abolishment of H3K4me. Consequently, the yield of traps and conidia of ΔAoSet1 was significantly lower than that of the WT strain, and the growth rate and pathogenicity were also compromised. Moreover, H3K4 trimethylation was enriched mainly in the promoter of two bZip transcription factor genes (AobZip129 and AobZip350) and ultimately up-regulated the expression level of these two transcription factor genes. In the ΔAoSet1 and AoH3 K4A strains, the H3K4me modification level was significantly decreased at the promoter of transcription factor genes AobZip129 and AobZip350. These results suggest that AoSET1-mediated H3KEme serves as an epigenetic marker of the promoter region of the targeted transcription factor genes. Furthermore, we found that AobZip129 negatively regulates the formation of adhesive networks and the pathogenicity of downstream AoPABP1 and AoCPR1. Our findings confirm that the epigenetic regulatory mechanism plays a pivotal role in regulating trap formation and pathogenesis in NTFs, and provide novel insights into the mechanisms of interaction between NTFs and nematodes., (© 2023. Science China Press.)