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The feasibility of single-walled carbon nanotubes (SWCNTs) as adsorbents for solid-phase microextraction was investigated by using organochlorine pesticides (OCPs) as model compounds. SWCNTs were attached onto a stainless steel wire through organic binder. Potential factors affecting the extraction efficiency were optimized, including extraction time, extraction temperature, desorption time, desorption temperature, and salinity. The developed method has a linear range of 2-800 ng/L for most analytes, with coefficients of correlation ranging from 0.9911 to 0.9996, LODs ranged from 0.19 to 3.77 ng/L (S/N = 3), and RSDs in the range of 3.5-13.9% (n = 5). Compared with the commercial PDMS fiber, the SWCNT fiber has better thermal stability (over 350 degrees C) and longer life span (over 150 times). The developed method was applied to determine trace OCPs in lake water and wastewater samples with external standard calibration. Results showed that OCP contamination was very low in these samples, and HCHs were detected in almost all water samples while DDT concentrations were almost under detection limits in these samples. Recoveries obtained at 20 ng/L spiking level were in the range of 88.4-111% for OCPs in lake water. For wastewater samples, however, the recoveries were satisfactory for HCHs (63.6-97.1%) but relatively low for DDTs (44.7-116%) due to the high content of organic matter in wastewater.

Abstract. Three extraction systems including shaking, ultrasonic and microwave-assisted extraction were evaluated. Water and phosphate buffer were tested for the extraction of arsenic compounds in polluted soil, describing the water-soluble or plant-available fraction. The stabilities and recoveries of various arsenic species indicated that no obvious changes of species occurred during the extraction process. The raw extracts were cleaned up by C 18 cartridge before analysis. Having optimized the extraction conditions, the arsenic species in polluted soil and ore from the different pollution sources were extracted by microwave-assisted extraction with 0.5 M phosphate buffer as extractant. Arsenic species were quantitatively determined by high performance liquidchromatographyon-line coupledwith hydridegeneration atomic fluorescence spectrometry (HPLC-HG-AFS). As(III) and As(V) were the major arsenic species in the polluted soil samples resulting from irrigation by waste water. As V was the only form found in the rotten ore sampled in mining area. During the extraction process, the recoveries of spiked As(III), As(V), DMA(V) and MMA(V) were 85.4 AE 7.2%, 80.2 AE 6.7%, 101.6 AE 6.7% and 98.8 AE 9.1%, respectively, showing that most water-soluble arsenic could be measured.

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Single nucleotide polymorphisms in the promoter region of interleukin-18 (IL-18), an inflammatory cytokine, have been linked to susceptibility to many diseases, including cancer and immune dysfunction. Here, we explored the potential association between the IL-18 -607C/A (rs1946518) promoter region polymorphism and susceptibility to ischemic stroke (IS). This locus was amplified from peripheral blood samples of 386 IS patients (cases) and 364 healthy individuals (controls) by the polymerase chain reaction with sequence-specific primers. Significant differences were observed by the χ2 test in the -607C/A (rs1946518) genotype and allele frequencies between cases and controls (P < 0.05). Furthermore, after excluding for age, gender, smoking status, and hypertension, logistic regression indicated that IS susceptibility of -607C carriers increased 1.6 times (OR = 1.601, 95%CI = 1.148-2.233, P = 0.006) compared to -607A carriers. Additionally, similar increases in IS risk were noted for male patients or patients less than 65 years old. In conclusion, IL-18 -607C/A (rs1946518) promoter polymorphism is associated with IS susceptibility, and the C allele may confer increased IS risk.

Stroke is a leading cause of cardiovascular morbidity, economic and social burden and mortality. Novel approaches are needed to address stroke prevention and treatment. The purpose of this study was to explore the effects of aloe polysaccharide on caspase-3 expression following cerebral ischemia reperfusion injury in rats. Male Wistar rats were randomly divided into 5 groups (16 rats in each group): aloe polysaccharide, ginkgo leaf tablet, nimodipine, model and sham surgery groups. The rats were administered the appropriate drug or normal saline for 7 days by gavage. A rat model of cerebral ischemia and reperfusion injury was established using the middle cerebral artery occlusion (MCAO) model. Caspase-3 protein and mRNA expression levels in the cerebral cortex were detected by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Results showed that caspase-3 protein and mRNA expression levels in the cerebral cortex in the aloe polysaccharide, ginkgo leaf tablet and nimodipine groups were significantly lower compared with the model group and were higher than the sham surgery group (P<0.05). No significant difference was observed in caspase-3 protein and mRNA expression among the aloe polysaccharide, the ginkgo leaf tablet and the nimodipine groups (P>0.05). In conclusion, aloe polysaccharide has a protective effect on cerebral ischemia that may be due to the inhibition of neuronal cell apoptosis.

Background Alzheimer’s disease (AD) is an age-related neurodegenerative disease and exercises might mitigate the progression of AD. This investigation aimed to manifest the potential mechanism of exercises in AD. Methods Morris water maze (MWM) test was conducted to evaluate the cognitive function in APP/PS1 mice. Quantitative real-time PCR was performed to detect the expression of HOTAIR and miR-130a-3p. The enzyme-linked immunosorbent assay was applied to appraise the concentration of IL-1β, IL-6, and TNF-α. A luciferase report experiment was implemented to substantiate the relationship between miR-130a-3p and HOTAIR. Results Exercises contributed to the elevated expression of HOTAIR. The findings of MWM implied HOTAIR inhibited the impacts of voluntary exercises on escape latency, distance moved, percentage of time spent in the target quadrant, platform crossing times, and inflammation. MiR-130a-3p mediated the function of HOTAIR on cognitive ability and inflammation. Conclusion HOTAIR participated in the regulation of exercises on AD by sponging miR-130a-3p.

Abstract.A new method based on hollow fiberprotected liquid-phase microextraction (LPME) was developed for the simultaneous determination of atrazine, desethyl atrazine and desisopropyl atrazine in environmental water samples. In LPME, analytes were extracted into 1-octanol immobilized in the micropores of a poly(vinylidene fluoride) porous hollow fiber membrane, and back extracted into the acceptor (4 M HCl) filled in the lumen of the hollow fiber. After LPME, the analytes trapped in the acceptor were analyzed with high-performance liquid chromatography after neutralization. The effect of extraction factors such as sample pH, acceptor pH, salinity, extraction time, stirring rate, and humic acid were studied. Under the optimized conditions, the limits of detection and relative standard deviations were respectively in the range of 0.5-1.0 mg L À1 and 3.9-4.7% (n ¼ 5). The proposed method was applied to determine atrazine, desethyl atrazine and desisopropyl atrazine in wastewater and groundwater samples. The three analytes were below the limits of detection, but good relative spiked recoveries over 90.1 AE 5.9% at 5 mg L À1 spiked level were obtained.