Sucrose Solution Ingestion Exacerbates Dinitrofluorobenzene-Induced Allergic Contact Dermatitis in Rats.

Allergic dermatitis is a skin disease with growing prevalence worldwide that has been associated with diets high in fats and sugars. Regular consumption of sucrose-containing beverages may increase the risk for several health problems, including allergic diseases and particularly asthma, but the association between sucrose consumption and allergic dermatitis is understudied. We investigated the effects of sucrose solution intake on allergic contact dermatitis in rats and found early exacerbation of 2,4-dinitrofluorobenzene (DNFB)-induced disease symptoms and altered composition of the gut microbiota after 14 d of intake. The levels of short-chain fatty acids-produced by fermentation by the intestinal microbiota-were not affected in the cecal contents and feces but decreased in the blood; this effect was especially notable for acetate. To restore blood acetate concentrations, triacetin was mixed with a 10% sucrose solution and fed to the rat model. This strategy prevented the early exacerbation of DNFB-induced symptoms. The decreased absorption of short-chain fatty acids from the intestinal lumen was not linked to the decreased expression of short-chain fatty acid transporters in the small intestine; instead, the mechanism involves a reduction in the sodium concentration in the intestinal lumen due to increased expression of sodium-glucose transporter 1 (SGLT1).

[A protective effect of acetaminophen on ibuprofen-induced small intestinal damage in rats via the suppression of MMP-13].

BACKGROUND & AIMS: Capsule endoscopy has revealed that nonsteroidal anti-inflammatory drugs may cause damage not only to the stomach but also to the small intestine, which has become one of the most serious issues in gastroenterology. However, few studies have reported the effect of ibuprofen (IBP), which is widely prescribed worldwide, on the small intestine, and it remains unclear whether IBP can cause small intestinal damage. We have previously shown that acetaminophen (APAP), which is used as an antipyretic/analgesic drug, inhibits IBP-induced gastric damage by suppressing matrix metalloprotease-13 (MMP-13) gene expression. In this study, we investigated the ability of IBP to induce small intestinal damage and the efficacy of APAP against IBP-induced small intestinal damage in rats. MAIN METHODS: Nonfasted male Sprague-Dawley rats were orally administered with IBP (200mg/kg) and then euthanized at various time points (0, 4, 8, 16, and 24h) after the administration. The small intestine, jejunum, and ileum were removed, and intestinal lesions were measured. To elucidate the efficacy of APAP against IBP-induced small intestinal damage, the rats were treated with IBP (200mg/kg) with or without APAP (200mg/kg), and small intestinal damage was evaluated 24h after the administration. Moreover, the expression levels of GAPDH, TNFα, iNOS, and MMP-13 genes were determined at various time points (8, 16, and 24h) by RT-qPCR. KEY FINDINGS: The oral administration of IBP induced obvious small intestinal damage, which was found to be significant at 24h (p<0.05 vs 0h, Dunnett's test). The coadministration of APAP significantly prevented IBP-induced damage (p<0.05, Student's t-test). In addition, the expression levels of TNFα and iNOS genes were significantly increased by IBP (p<0.01 and p<0.05 vs. vehicle, respectively, Tukey-Kramer test), whereas the cotreatment with APAP suppressed the increases at 8h. Moreover, compared with the vehicle, the IBP treatment significantly increased the expression level of the MMP-13 gene (p<0.01) at each time point (8, 16, and 24h, Tukey-Kramer test), whereas the APAP cotreatment significantly suppressed the increase (p<0.01 vs. IBP at 8h, p<0.05 vs. IBP at 16 and 24h, Tukey-Kramer test). CONCLUSIONS: This study suggested that a single administration of IBP was associated with the risk of inducing small intestinal ulcers in rats, and APAP could prevent IBP-induced small intestinal damage by suppressing the MMP-13 gene expression.

Leptin stimulates gonadotropin release and ovarian development in marine teleost chub mackerel.

Leptin transmits information about energy stored in the periphery to the reproductive axis and is an essential signal for puberty initiation in mammals; however, to date, few studies have focused on the direct effects of leptin stimulation on reproductive factors in fish. This study demonstrated the effect of leptin stimulation on important reproductive factors and ovarian development in the marine teleost chub mackerel (Scomber japonicus). We prepared recombinant leptin and conducted functional analyses through in vitro bioassays using primary pituitary cells, long-term leptin treatment administered to pre-pubertal females, and intracerebroventricular (ICV) administration. The results showed that leptin stimulation strongly induced gonadotropin (follicle-stimulating hormone: FSH and luteinizing hormone: LH) secretion from pituitary cells collected from pre-pubertal females, and that long-term leptin treatment significantly promoted ovarian development and triggered pubertal onset. Furthermore, ICV administration of leptin did not affect kisspeptin gene expression but significantly upregulated gonadotropin-releasing hormone 1 (gnrh1), fshb and lhb gene expression in sexually immature females. These results strongly suggest leptin as an important signal for reproductive-axis activation in chub mackerel.

Chiral-selective etching effects on carbon nanotube growth at edge carbon atoms.

Chemical vapor deposition (CVD) utilizing metal cluster nanoparticle catalysts is commonly used to synthesize carbon nanotubes (CNT), with oxygen-containing species such as water or alcohol included in the feedstock for enhanced yield. However, the etching effect of these additives on the growth mechanism has rarely been investigated, despite evidence suggesting that etching potentially affects the chirality distribution of product CNTs. We used quantum chemical methods to study how water-based etchant radicals (OH and H) may enhance the chiral selectivity during CVD growth using CNT cap models. Chemical reactivities of the caps with the etchant radicals were evaluated using density functional theory (DFT). It was found that the reactivities on the cap edges correlate with the chirality of the caps. These results suggest that proper selection of etchant species can provide opportunities for selective chirality control of the product CNTs. © 2018 Wiley Periodicals, Inc.

Electrically Activated Conductivity and White Light Emission of a Hydrocarbon Nanoring-Iodine Assembly.

Numerous otherwise difficult applications have been realized with materials, the chemical/physical properties of which can be controlled by external stimuli such as heat, pressure, photo-irradiation, and voltage bias. However, the complexity of design and the lack of easy-to-conduct synthetic methods make the creation of on-demand stimuli responsive materials a formidable task. Here we report an electric-stimuli-responsive multifunctional material, [10]CPP-I: crystalline assembly of a hydrocarbon nanoring ([10]cycloparaphenylene: [10]CPP) as an "electro-responsive porous host" and iodine as a "potentially functional molecule". Through applying electric stimulus, [10]CPP-I turned to exhibit two attractive properties: electronic conductivity and white light emission. We revealed that electric stimuli trigger the cascade formation of polyiodide chains inside the [10]CPP assembly through charge transfer, leading to the emergence of these properties. This "responsive porous host" approach is expected to be applicable for different stimuli, and opens the path for devising a generic strategy to the development of stimuli-responsive materials.

A New Triazine-Based Covalent Organic Framework for High-Performance Capacitive Energy Storage.

The new covalent organic framework material TDFP-1 was prepared through a solvothermal Schiff base condensation reaction of the monomers 1,3,5-tris-(4-aminophenyl)triazine and 2,6-diformyl-4-methylphenol. Owing to its high specific surface area of 651 m2 g-1 , extended π conjugation, and inherent microporosity, TDFP-1 exhibited an excellent energy-storage capacity with a maximum specific capacitance of 354 F g-1 at a scan rate of 2 mV s-1 and good cyclic stability with 95 % retention of its initial specific capacitance after 1000 cycles at 10 A g-1 . The π-conjugated polymeric framework as well as ionic conductivity owing to the possibility of ion conduction inside the micropores of approximately 1.5 nm make polymeric TDFP-1 a favorable candidate as a supercapacitor electrode material. The electrochemical properties of this electrode material were measured through cyclic voltammetry, galvanic charge-discharge, and electrochemical impedance spectroscopy, and the results indicate its potential for application in energy-storage devices.