[Antinociceptive efficacy of QO-58 in the monosodium lodoacetate rat model for osteoarthritis pain]

Objective: To determine the effects of QO-58 on pain behavior associated with monosodium iodoacetate (MIA)-induced OA. Methods: The OA model was established with an intra-articular injection of 3 mg/50 MIA through the right patellar ligament. Then the model rats were treated with 50 mg/kg QO-58 by intraperitoneal injection, and pain-related behaviors were assessed by single administration and multiple administrations of QO-58. Results: Single adminstration of QO-58 increased the mechanical threshold and prolonged the withdrawal latency of OA pain with the antinociceptive effect occurring at 6 h and 10 h. Compound QO-58 was administered intraperitoneally once a day from day 10 to 14. QO-58 significantly increased the mechanical threshold and prolonged the withdrawal latency of OA rats at 12 and 14 days. Conclusion: QO-58 showed antinociceptive effects for OA pain in the MIA model after pain development. QO-58 may be an alternative therapeutic treatment for OA.

Effects and underlying mechanisms of irisin on the proliferation and apoptosis of pancreatic β cells

Pancreatic β cell dysfunction and reduction due to glucose toxicity play a crucial role in the development of type 2 diabetes mellitus (T2DM). Irisin, a novel exercise-induced myokine, reduces obesity, improves insulin resistance and lowers blood glucose by promoting the browning of white adipose tissue, thereby enhancing thermogenesis and increasing energy expenditure. Recent studies have reported that irisin promotes cell proliferation and protects cells from apoptosis. However, the effects of irisin on pancreatic β cells are unknown. Thus, the aim of this study was to investigate the effects and the potential underlying mechanisms of irisin on pancreatic β cell proliferation and apoptosis induced by high glucose. Both in vitro (INS-1 cells) and in vivo (a T2DM rat model) experiments were conducted. Irisin significantly increased the proliferation of INS-1 cells, with the most significant effect observed at 24 h with 100 ng/ml irisin. Irisin also promoted INS-1 cell proliferation via the ERK and p38 MAPK signaling pathways, protected the cells from high-glucose-induced apoptosis by regulating the expression of caspases, Bad, Bax, Bcl-2 and Bcl-xl, and improved pancreatic β cell function. Irisin significantly reduced the body weight and blood glucose values and increased the serum insulin levels of the diabetic rats. An oral glucose tolerance test (OGTT) indicated that irisin also improved the glucose tolerance of T2DM rats. Together, these findings suggest that irisin may have applications in the prevention and treatment of T2DM because of its protective effect on the secretion of pancreatic β cells.

[PM2.5 and polluted gas exposure induced acute injury in rats'larynx membrane]

Objective:To study acute injury of rat's larynx membrane which were exposured to PM2.5 and polluted gas in serious air pollution. Method:Rats were divided into 3 groups of 5 animals each, the normal control group, gas exposured group, PM2.5 +gas exposured group. The control group served as the normal healthy control, rats of the gas exposured group had been exposured polluted gas in the A cabin, rats of PM2.5 +gas exposured group had been exposured PM2.5 and polluted gas in the B cabin. The total exposure time was six days. We collected specimen from 3 groups immediately after exposure. Histopathological changes in the rat's larynx membrane were assessed using hematoxylin and eosin staining(HE), the expression of IL-1β in laryngeal mucous membrane were assessed using immunohistochemical staining(IHC), and the ultrastructure changes were observed under TEM. Result:HE staining showed the rat's laryngeal mucosa cells in the normal control group had no obvious abnormalities, laryngeal mucosa of rats in the two experimental group had different degrees of cell proliferation, cell polarity change, etc. IHC staining showed that there's no obvious expression of IL-1β in laryngeal mucous membrane in the normal control group, and positive expression in the two experimental group. TEM showed the control group had no obvious abnormalities, the laryngeal mucosa cells in the two groups of experimental groups had been found irregular nucleus and damaged mitochondria. Conclusion:Exposed to PM2.5 and polluted gas in severe atmospheric pollution 6 days, the acute damage in rats laryngeal mucosa can be observed.

The development of nanostructure assisted isothermal amplification in biosensors

Developing simple and inexpensive methods to ultrasensitively detect biomarkers is important for medical diagnosis, food analysis and environmental security. In recent years, isothermal amplifications with sensitivity, high speed, specificity, accuracy, and automation have been designed based on interdisciplinary approaches among chemistry, biology, and materials science. In this article, we summarize the advances in nanostructure assisted isothermal amplification in the past two decades for the detection of commercial biomarkers, or biomarkers extracted from cultured cells or patient samples. This article has been divided into three parts according to the ratio of target-to-signal probe in the detection strategy, namely, the N : N amplification ratio, the 1 : N amplification ratio, and the 1 : N(2) amplification ratio.

Experimental studies of thermal environment and contaminant transport in a commercial aircraft cabin with gaspers on

Gaspers installed in commercial airliner cabins are used to improve passengers' thermal comfort. To understand the impact of gasper airflow on the air quality in a cabin, this investigation measured the distributions of air velocity, air temperature, and gaseous contaminant concentration in five rows of the economy-class section of an MD-82 commercial aircraft. The gaseous contaminant was simulated using SF6 as a tracer gas with the source located at the mouth of a seated manikin close to the aisle. Two-fifths of the gaspers next to the aisle were turned on in the cabin, and each of them supplied air at a flow rate of 0.66 l/s. The airflow rate in the economy-class cabin was controlled at 10 l/s per passenger. Data obtained in a previous study of the cabin with all gaspers turned off were used for comparison. The results show that the jets from the gaspers had a substantial impact on the air velocity and contaminant transport in the cabin. The air velocity in the cabin was higher, and the air temperature slightly more uniform, when the gaspers were on than when they were off, but turning on the gaspers may not have improved the air quality.

Cellulose conjugated FITC-labelled mesoporous silica nanoparticles: intracellular accumulation and stimuli responsive doxorubicin release

Herein, we design novel cellulose conjugated mesoporous silica nanoparticle (CLS-MSP) based nanotherapeutics for stimuli responsive intracellular doxorubicin (DOX) delivery. DOX molecules are entrapped in pores of the fabricated mesoporous silica nanoparticles (MSPs) while cellulose is used as an encapsulating material through esterification on the outlet of the pores of the MSPs to avoid premature DOX release under physiological conditions. In in vitro studies, stimuli responsive DOX release is successfully achieved from DOX loaded cellulose conjugated mesoporous silica nanoparticles (DOX/CLS-MSPs) by pH and cellulase triggers. Intracellular accumulation of DOX/CLS-MSPs in human liver cancer cells (HepG2 cells) is investigated through confocal microscope magnification. Cell viability of HepG2 cells is determined as the percentage of the cells incubated with DOX/CLS-MSPs compared with that of non-incubated cells through an MTT assay.

Quencher group induced high specificity detection of telomerase in clear and bloody urines by AIEgens

Telomerase is a widely used tumor biomarker for early cancer diagnosis. On the basis of the combined use of aggregation-induced emission (AIE) fluorogens and quencher, a quencher group induced high specificity strategy for detection of telomerase activity from cell extracts and cancer patients' urine specimens was creatively developed. In the absence of telomerase, fluorescence background is extremely low due to the short distance between quencher and AIE dye. In the addition of telomerase, fluorescence enhances significantly. The telomerase activity in the E-J, MCF-7, and HeLa extracts equivalent to 5-10 000 cells can be detected by this method in ∼1 h. Furthermore, the distinguishing of telomerase extracted from 38 cancer and 15 normal urine specimens confirms the reliability and practicality of this protocol. In contrast to our previous results (Anal. Chem. 2015, 87, 6822-6827), these advanced experiments obtain more remarkable specificity.

Heavy metal accumulation and source analysis in greenhouse soils of Wuwei District, Gansu Province, China

Greenhouse soils and arable (wheat field) soil samples were collected to identify the effects of greenhouse cultivation on the accumulation of six heavy metals (Cd, Cu, Zn, Pb, Cr, and Ni) and to evaluate the likely sources responsible for heavy metal accumulation in the irrigated desert soils of Wuwei District, China. The results indicated that the mean concentrations of Cd, Cu, Zn, Pb, Cr, and Ni were 0.421, 33.85, 85.31, 20.76, 53.12, and 28.59 mg kg(-1), respectively. The concentrations of Cd, Cu, and Zn in greenhouse soils were 60, 23, and 14% higher than those in arable soils and 263, 40, and 25% higher than background concentrations of natural soils in the study area, respectively. These results indicated that Cd, Cu, and Zn accumulation occurred in the greenhouse soils, and Cd was the most problematically accumulated heavy metal, followed by Cu and Zn. There was a significant positive correlation between the concentrations of Cd, Cu, and Zn in greenhouse soils and the number of years under cultivation (P < 0.05). Greenhouse cultivation had little impact on the accumulation of Cr, Ni, or Pb. Correlation analysis and principal component analysis suggested that the accumulation of Cd, Cu, and Zn in greenhouse soils resulted mainly from fertilizer applications. Our results indicated that the excessive and long-term use of fertilizers and livestock manures with high heavy metal levels leads to the accumulation of heavy metals in soils. Therefore, rational fertilization programs and reductions in the concentrations of heavy metals in both fertilizers and manure must be recommended to maintain a safe concentration of heavy metals in greenhouse soils.

Target-specific 3D DNA gatekeepers for biomimetic nanopores

3D cross-linked DNA superstructures switch off the ionic flux through solid-state nanopores with extremely high ON-OFF ratios of 10(3) -10(5) . This gating mechanism can be generally applicable in a wide range of nanopores with opening diameters up to 650 nm. The 3D bio-supramolecular gatekeepers outperform previous low-dimensional or simple-structured DNA functional components.

Real-time monitoring of enzyme-free strand displacement cascades by colorimetric assays

The enzyme-free toehold-mediated strand displacement reaction has shown potential for building programmable DNA circuits, biosensors, molecular machines and chemical reaction networks. Here we report a simple colorimetric method using gold nanoparticles as signal generators for the real-time detection of the product of the strand displacement cascade. During the process the assembled gold nanoparticles can be separated, resulting in a color change of the solution. This assay can also be applied in complex mixtures, fetal bovine serum, and to detect single-base mismatches. These results suggest that this method could be of general utility to monitor more complex enzyme-free strand displacement reaction-based programmable systems or for further low-cost diagnostic applications.

Polar organic solvents accelerate the rate of DNA strand replacement reaction

Acceleration of the reaction rate by polar organic solvents during both simple and complicated DNA strand replacement reactions is reported.

Speeding up the self-assembly of a DNA nanodevice using a variety of polar solvents

The specific recognition and programmable assembly properties make DNA a potential material for nanodevices. However, the more intelligent the nanodevice is, the more complicated the structure of the nanodevice is, which limits the speed of DNA assembly. Herein, to address this problem, we investigate the performance of DNA Strand Displacement Reaction (DSDR) in a mixture of polar organic solvents and aqueous buffer and demonstrate that the organic polar solvent can speed up DNA self-assembly efficiently. Taking DSDR in 20% ethanol as an example, first we have demonstrated that the DSDR is highly accelerated in the beginning of the reaction and it can complete 60% of replacement reactions (160% enhancement compared with aqueous buffer) in the first 300 seconds. Secondly, we calculated that the ΔΔG of the DSDR in 20% ethanol (-18.2 kcal mol(-1)) is lower than that in pure aqueous buffer (-32.6 kcal mol(-1)), while the activation energy is lowered by introducing ethanol. Finally, we proved that the DSDR on the electrode surface can also be accelerated using this simple strategy. More importantly, to test the efficacy of this approach in nanodevices with a complicated and slow DNA self-assembly process, we apply this strategy in the hybridization chain reaction (HCR) and prove the acceleration is fairly obvious in 20% ethanol, which demonstrates the feasibility of the proposed strategy in DNA nanotechnology and DNA-based biosensors.

Imparting biomolecules to a metal-organic framework material by controlled DNA tetrahedron encapsulation

Recently, the incorporation of biomolecules in Metal-organic frameworks (MOFs) attracts many attentions because of controlling the functions, properties and stability of trapped molecules. Although there are few reports on protein/MOFs composites and their applications, none of DNA/MOFs composite is reported, as far as we know. Here, we report a new composite material which is self-assembled from 3D DNA (guest) and pre-synthesized MOFs (host) by electrostatic interactions and hydrophilic interactions in a well-dispersed fashion. Its biophysical characterization is well analyzed by fluorescence spectroscopy, quartz crystal microbalance (QCM) and transmission electron microscopy (TEM). This new composite material keeps 3D DNA nanostructure more stable than only 3D DNA nanostructure in DI water at room temperature, and stores amounts of genetic information. It will make DNA as a guest for MOFs and MOFs become a new platform for the development of DNA nanotechnology.

Cardiovascular effects of ethanol extract of Rubus chingii Hu (Rosaceae) in rats: an in vivo and in vitro approach

Rubus chingii Hu (Rosaceae) is an important traditional Chinese medicine that has been used to improve function of the kidney and treat excessive polyuria. However, the effects of Rubus chingii on the cardiovascular system and its pharmacological mechanisms of action have not been studied. The aim of the present study was to evaluate the cardiovascular effects of ethanol extract of Rubus chingii (ERC) in rats. The changes in systolic blood pressure and heart rate of rats and vascular tone of aortic rings in in vitro were measured using pressure transducer and force transducer, respectively, connected to a multichannel recording system. ERC decreased systolic blood pressure and heart rate in a concentration-dependent manner. ERC induced vasorelaxation in a concentration-dependent manner. The ERC-induced vasorelaxation was not observed in the absence of the endothelium. The vasorelaxant effect of ERC was significantly attenuated by inhibition of endothelial NO synthase (eNOS), soluble guanylyl cyclase (sGC), or Ca(2+) entry from extracellular sources with L-NAME, ODQ, diltiazem, or extracellular Ca(2+) depletion, respectively. Similarly, an inhibition of Akt with wortmannin attenuated the ERC-induced vasorelaxation. Modulators of the store-operated Ca(2+) entry, thapsigargin, Gd(3+), and 2-aminoethyl diphenylborinate markedly attenuated the ERC-induced vasorelaxation. Furthermore, 4-aminopyridine an inhibitor of voltage-dependent K(+) (KV) channel, significantly attenuated the ERC-induced vasorelaxation. However, tetraethylammonium and glibenclamide, had no significant effect on the ERC-induced vasorelaxation. Indomethacin, atropine, and propranolol had no effects on the ERC-induced vasorelaxation. The present study demonstrates that ERC induces vasorelaxation via endothelium-dependent two-step signaling: an activation of the Ca(2+)-eNOS-NO signaling in the endothelial cells and then subsequent stimulation of the NO-sGC-cGMP-KV channel signaling in the vascular smooth muscle cells. The Akt-eNOS pathway is also suggested to be involved in this relaxation. Also, the findings suggest that the ERC-induced vasorelaxation is closely related to the hypotensive action of the agent.

Constructing tunable nanopores and their application in drug delivery

Inspired by biological cell membranes, various "smart" and efficient gating nanoporous devices have been proposed to imitate and to understand life processes. Nanodevices under development with enhanced gating efficiency could play pivotal roles in biosensing and drug delivery. In this Perspective, we highlight an important development by Willner and colleagues that is detailed in this issue of ACS Nano. They designed a new "smart" nanodevice with both "sense" and "release" functionalities for drug delivery based on a nanoporous material, mesoporous silica nanoparticles. We outline recent progress in designing intelligently gated nanoporous devices in material science and nanotechnology. We also summarize new strategies designed for drug delivery based on mesoporous materials. With continuing efforts, we expect more powerful nanodevices to be developed and used in clinical and other real-word applications.