Ultrapreconcentration and determination of organophosphorus pesticides in water by solid-phase extraction combined with dispersive liquid-liquid microextraction and high-performance liquid chromatography.

Solid-phase extraction coupled with dispersive liquid-liquid microextraction was developed as an ultra-preconcentration method for the determination of four organophosphorus pesticides (isocarbophos, parathion-methyl, triazophos and fenitrothion) in water samples. The analytes considered in this study were rapidly extracted and concentrated from large volumes of aqueous solutions (100 mL) by solid-phase extraction coupled with dispersive liquid-liquid microextraction and then analyzed using high performance liquid chromatography. Experimental variables including type and volume of elution solvent, volume and flow rate of sample solution, salt concentration, type and volume of extraction solvent and sample solution pH were investigated for the solid-phase extraction coupled with dispersive liquid-liquid microextraction with these analytes, and the best results were obtained using methanol as eluent and ethylene chloride as extraction solvent. Under the optimal conditions, an exhaustive extraction for four analytes (recoveries >86.9%) and high enrichment factors were attained. The limits of detection were between 0.021 and 0.15 µg/L. The relative standard deviations for 0.5 µg/L of the pesticides in water were in the range of 1.9-6.8% (n = 5). The proposed strategy offered the advantages of simple operation, high enrichment factor and sensitivity and was successfully applied to the determination of four organophosphorus pesticides in water samples.

[Short Text Classification of EMR Based on Entities and Dependency Parser].

Nowadays, text classification and text mining of Electronic Medical Record (EMR) have become the basis of the Big Data research in biomedical fields. This paper proposes a method using entity dictionaries and dependency parser as the feature to do the classification of short texts in EMR. It used NLP to preprocess the texts first including sentence segmentation, word segmentation, part of speech and entity extraction. Then several entity dictionaries were built according to the result of NLP. After that the TF-IDF and LSA were deployed to select the vocabulary feature. Then considering the characters of EMR, dependency parser was done to the texts and triple dependency relation features would be used as the expanding feature for text classification. The result of the experiment shows that comparing to the classification which used vocabulary features only, the proposed methods can effectively improve the performance of classifier and the precision and F-value are obviously higher.

Stim1- and Orai1-mediated store-operated calcium entry is critical for angiotensin II-induced vascular smooth muscle cell proliferation.

AIM: Despite the fact that angiotensin (Ang) II is a critical regulator of the proliferation and migration of vascular smooth muscle cells (VSMCs), the effect of Ang II on VSMC proliferation has remained unclear. In this study, we determined whether Stim1- and Orai1-mediated store-operated calcium (Ca(2+)) entry (SOCE) plays a critical role in Ang II-induced VSMC proliferation and Ang II-accelerated neointimal growth after balloon injury of rat carotid arteries. METHODS AND RESULTS: Knockdown of Stim1 and Orai1, putative calcium sensors/modulators, suppressed Ang II-mediated Ca(2+) entry and cell proliferation in synthetic VSMCs. Stim1 and Orai1 short interfering RNAs (siRNAs) decreased neointimal growth induced by Ang II in balloon-injured rat carotid arteries. Ang II significantly increased the expression of Stim1 and Orai1 in neointima. In addition, our results showed that receptor subtype-1 (AT1) significantly contributed to Ang II-induced Ca(2+) entry and proliferation of synthetic VSMCs. However, we found that transient receptor potential canonical 1 (Trpc1) had no effect on Ang II-induced SOCE or cell proliferation of synthetic VSMCs. CONCLUSIONS: We show for the first time that Stim1- and Orai1-mediated SOCE may be critical for Ang II-induced VSMC proliferation. This provides important information with respect to targeting cardiovascular diseases under the enhanced renin-Ang system.

[FT-Raman spectroscopic investigation on hypothyroid cancer].

The normal and malignant tissues from hypothyroid were investigated by FT-Raman spectroscopy. The results show that two characteristic Raman spectral peaks of normal tissues appeared at 503 and 758 cm(-1) (corresponding to theextension vibration of C--I band and the vibration of benzene rings respectively) in the range of 400-3500 cm(-1). The two peaks disappeared at malignant tissues. The intensity of the characteristic vibration peaks of normal tissues appearing at 3 062 and 1 003 cm(-1) corresponding to tyrosine weakened in malignant tissues. Thus, FT-Raman spectroscopy is a potential method in the diagnosis of hypothyroid cancer.