[Determination of three new herbicide residues in soil, sediment and water by liquid chromatography-tandem mass spectrometry].

Herbicides play an important role in preventing and controlling weeds and harmful plants and are increasingly used in agriculture, forestry, landscaping, and other fields. However, the effective utilization rate of herbicides is only 20%-30%, and most herbicides enter the atmosphere, soil, sediment, and water environments through drift, leaching, and runoff after field application. Herbicide residues in the environment pose potential risks to ecological safety and human health. Therefore, establishing analytical methods to determine herbicide residues in environmental samples is of great importance. In this study, an analytical method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) in positive electrospray ionization mode (ESI+) was developed for the determination of isoxaflutole, metazachlor, and saflufenacil residues in soil, sediment, and water. The instrumental detection parameters, including electrospray ionization mode, mobile phase, and chromatographic column, were optimized. The mobile phases were methanol (A) and 0.1% formic acid aqueous solution (B). Gradient elution was performed as follows: 0-1.0 min, 60%A; 1.0-2.0 min, 60%A-90%A; 2.0-3.0 min, 90%A; 3.0-4.0 min, 90%A-60%A; 4.0-5.0 min, 60%A. The samples were salted after extraction with acetonitrile and cleaned using a C18 solid-phase extraction column. Different solid-phase extraction columns and leaching conditions were investigated during sample pretreatment. Working curves in the neat solvent and matrix were constructed by plotting the measured peak areas as a function of the concentrations of the analytes in the neat solvent and matrix. Good linearities were found for isoxaflutole, metazachlor, and saflufenacil in the solvent and matrix-matched standards in the range of 0.0005-0.02 mg/L, with r≥0.9961. The matrix effects of the three herbicides in soil, sediment, and water ranged from -10.1% to 16.5%. The limits of detection (LODs, S/N=3) for isoxaflutole, metazachlor, and saflufenacil were 0.05, 0.01, and 0.02 µg/kg, respectively. The limits of quantification (LOQs, S/N=10) for isoxaflutole, metazachlor, and saflufenacil were 0.2, 0.05, and 0.05 µg/kg, respectively. The herbicides were applied to soil, sediment, and water at spiked levels of 0.005, 0.1, and 2.0 mg/kg, respectively. The average recoveries for isoxaflutole, metazachlor, and saflufenacil in soil, sediment, and water were in the ranges of 77.2%-101.9%, 77.9%-105.1%, and 80.8%-107.1%, respectively. The RSDs for isoxaflutole, metazachlor, and saflufenacil were in the ranges of 1.4%-12.8%, 1.2%-7.7%, and 1.5%-11.5%, respectively. The established method was used to analyze actual samples collected from four different sites in Zhejiang Province (Xiaoshan, Taizhou, Dongyang, and Yuhang) and one site in Heilongjiang (Jiamusi). The proposed method is simple, rapid, accurate, stable, and highly practical. It can be used to detect isoxaflutole, metazachlor, and saflufenacil residues in soil, sediment, and water and provides a reference for monitoring the residual pollution and environmental behavior of herbicides.

Insulin resistance in school-aged girls with overweight and obesity is strongly associated with elevated white blood cell count and absolute neutrophil count.

Background: The primary objective of the study was to discuss the sex differences in insulin resistance-induced changes in metabolic and inflammatory markers in school-aged children with overweight and obesity. Methods: A cross-sectional study of 800 children aged seven and twelve years was performed. Questionnaires, anthropometric data and fasting blood samples were collected. Results: Children with overweight and obesity showed statistically significant differences in multiple metabolic and inflammatory markers compared with children with normal BMI. The correlation coefficient (r) between white blood cell count, absolute neutrophil count, fasting plasma insulin, HOMA-IR, HOMA-ß, triglyceride, HDL-C, triglyceride/HDL ratio, alanine transaminase, serum uric acid, systolic blood pressure and BMI were higher in all children, but the linear relationships between white blood cell count, absolute neutrophil count and BMI were stronger in girls with overweight and obesity than in boys with overweight and obesity. Subsequently, HOMA-IR was shown to be more strongly associated with increased white blood cell count and absolute neutrophil count in school-aged girls with overweight and obesity by partial correlation analysis and the multiple linear regression analysis. Conclusions: Elevated white blood cell count and absolute neutrophil count in children with overweight and obesity, especially girls, can serve as markers of insulin resistance.

M-Phase Phosphoprotein 9 upregulation associates with poor prognosis and activates mTOR signaling in gastric cancer.

The function of M-Phase Phosphoprotein 9 (MPHOSPH9) has not been investigated in gastric cancer yet. In the present study, the public cancer databases Oncomine and TCGA were analyzed, and MPHOSPH9 was found upregulated in gastric cancer tumor tissues. Immunohistochemistry (IHC) was also carried out to further confirm the results, and IHC analysis showed MPHOSPH9 was elevated in tumor tissues compared with the paracancerous tissues. QRT-PCR analysis also revealed that MPHOSPH9 mRNA was upregulated in gastric cancer cell lines. In addition, Kaplan-Meier estimates showed gastric cancer patients with high MPHOSPH9 level predicted a poor prognosis. Then, Western blot and CCK-8 assay showed overexpressed MPHOSPH9 enhanced gastric cancer cell proliferation, but MPHOSPH9 knockdown suppressed gastric cancer cell proliferation. Additionally, Western blot showed that MPHOSPH9 regulated the activation of mTOR, and overexpressed MPHOSPH9 reduced the inhibitory effects of mTOR inhibitors on cell survival in gastric cancer cells. Taken together, our results suggested that MPHOSPH9 .could be an oncogene in gastric cancer by regulating mTOR signaling.

Comparative pharmacokinetics of bergenin, a main active constituent of Saxifraga stolonifera Curt., in normal and hepatic injury rats after oral administration.

Bergenin, isolated from the herb of Saxifrage stolonifera Curt. (Hu-Er-Cao) has hepatoprotective, anti-inflammatory, antitussive, and neuroprotective activities. The aim of the present study was to establish a simple, rapid, and sensitive RP-HPLC method for determination of bergenin in rat plasma and compare its oral pharmacokinetic behaviors in normal and CCl4-induced hepatic injury rats. With norisoboldine as an internal standard, chromatographic separation was performed on a C18 analytical column with acetonitrile and water (11 : 89, V/V) containing 0.1% formic acid as the mobile phase. A good linearity was obtained over the range of 100-10 000 ng·mL-1. The lower limit of quantification was 50 ng·mL-1. The developed method was successfully applied to a study of the pharmacokinetic difference of bergenin (100 mg·kg-1) between normal and hepatic injury rats after oral administration. Marked alterations of pharmacokinetic parameters in hepatic injury rats were observed. Compared to normal rats, the AUC(0-∞) of bergenin in hepatic injury rats was elevated to 2.11-fold and Cmax was increased by 130%, whereas CL value was only 55% of the normal rats, suggesting that the systemic exposure of bergenin was significantly increased under hepatic injury status.

Berberine improves neurogenic contractile response of bladder detrusor muscle in streptozotocin-induced diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Coptidis Rhizoma has been used to treat diabetes mellitus for more than 1400 years in China. Berberine, one of the main alkaloids of Coptidis Rhizoma, is a principal antidiabetic component of Coptidis Rhizoma. To investigate the effects of berberine on impaired neurogenic contractility of detrusor muscle from urinary bladder of rats with early stage diabetes. MATERIALS AND METHODS: The detrusor muscle strips were isolated from urinary bladders of streptozotocin-induced diabetic rats, 5% sucrose-induced diuretic rats or normal rats, and were placed in organ bath. The contractions induced by electrical field stimulation (EFS), carbachol, KCl, adenosine triphosphate, and the effects of berberine on those contractions were measured. RESULTS: The EFS- or KCl-induced contraction of detrusor muscle was significantly decreased in diabetic rats as compared with diuretic or normal rats. Atropine and suramin inhibited EFS-induced contraction. In diabetic rats, the atropine sensitive components were decreased in EFS-induced contraction of detrusor muscle, and the adenosine triphosphate-induced contraction was significantly increased. The carbachol-induced contrations were not different among groups. Berberine significantly potentiated EFS-induced contractions of detrusor muscle both from normal and diabetic rats, but the potentiated effect of BBR was more sensitive to atropine in diabetic rats. Berberine also potentiated adenosine triphosphate-induced contraction of detrusor muscle, but did not change carbachol- or KCl-induced contraction. CONCLUSION: The neurogenic contraction of urinary bladder detrusor muscle is decreased while purinergic contraction of bladder detrusor muscle is increased in rats with early stage diabetes. Berberine increases the neurogenic contractile response to EFS possibly via both presynaptic increasing neurotransmitters release and postsynaptic potentiation of purinergic transmitter-regulated response in rat urinary bladder detrusor; and in diabetic rats, berberine increases neurogenic contractile response mainly via the presynaptic increasing acetylcholine release.

[Roles of glucosinolates in the interrelationships between Brassicaceae plants and insects: a review].

Glucosinolates (GS) are the important secondary metabolites of Brassicaceae plants, playing an important role in regulating the interrelationships between Brassicaceae plants and insects. GS can protect Brassicaceae plants against euryphagous herbivorous pests because of the toxicity of GS and their breakdown products. However, oligophagous pests which have evolved manifold metabolic pathways to cope with the defensive compounds depended fully on GS and their volatile breakdown products for host-plant recognition and orientation. The GS ingested by herbivores are also toxic to carnivores, and can directly deter predators. On the other hand, predators and parasitoids are attracted by the volatile breakdown products of GS from the Brassicaceae plants damaged by herbivores. Based on the recent findings, this paper reviewed the defensive function of GS against herbivores, host selection of oligophagous pests, GS metabolic pathways of herbivores, induction of GS by herbivores, and effects of GS on the third tropic level. Future directions and techniques in this research field were also suggested.

Effects of imidazolines on neurogenic contraction in isolated urinary bladder detrusor strips from rabbit.

Moxonidine and clonidine, which are imidazoline compounds, are sympathetic modulators used as centrally acting antihypertensive drugs. Moxonidine, clonidine, and agmatine produce extensive effects in mammalian tissues via imidazoline recognition sites (or receptors) or α(2)-adrenoceptors. To investigate the effects of imidazolines on the function of the urinary bladder, we tested the effects of moxonidine, clonidine, and agmatine on the neurogenic contraction induced by electric field stimulation, and on the post-synaptic receptors in isolated urinary bladder detrusor strips from rabbit. Both moxonidine at 1.0-10.0 µmol/L and clonidine at 0.1-10.0 µmol/L inhibited electric-field-stimulation-induced contraction in a concentration-dependent manner, but not agmatine (10.0-1000.0 µmol/L). Both moxonidine and clonidine failed to affect carbachol or adenosine-triphosphate-induced contractions; however, 1000.0 µmol/L agmatine significantly increased these contractions. Our study indicates that (i) moxonidine and clonidine produce a concentration-dependent inhibition of the neurogenic contractile responses to electric field stimulation in isolated detrusor strips from male New Zealand rabbits; (ii) post-synaptic muscarinic receptor and purinergic receptor stimulation are not involved in the responses of moxinidine and clonidine in this study; (iii) the inhibitory effects of these agents are probably not mediated by presynaptic imidazoline receptors.

catena-Poly[[[diaqua-thulium(III)]-µ-6-carboxy-nicotinato-µ-pyridine-2,5-di-carboxyl-ato] dihydrate].

The title compound, {[Tm(C(7)H(3)NO(4))(C(7)H(4)NO(4))(H(2)O)(2)]·2H(2)O}(n), is isotypic with the analogous Tb(III) compound [Li et al. (2009 ▶). Acta Cryst. E65, m410]. All interatomic distances and angles and the hydrogen-bond geometries are very similar for the two structures. The refined Flack parameter of 0.49 (2) suggests inversion twinning.

Tetra-kis(µ-2,4-difluoro-benzoato)bis-[(2,4-difluoro-benzoato)(1,10-phenanthroline)gadolinium(III)].

In the title compound, [Gd(2)(C(7)H(3)F(2)O(2))(6)(C(12)H(8)N(2))(2)], the asymmetric unit comprises one Gd(3+) cation chelated by two 2,4-difluoro-benzoate and one 1,10-phenanthroline ligands. Two cations are linked into a centrosymmetric dimer via three bridging carboxyl-ate groups of 2,4-difluoro-benzoate ligands. Each Gd(3+) ion is nine-coordinated by seven O atoms and two N atoms.

Separation and identification of cis and trans isomers of 2-butene-1,4-diol and lafutidine by HPLC and LC-MS.

The cis and trans isomers separation of 2-butene-1,4-diol and lafutidine were studied by HPLC on two kinds of chiral columns: (S,S)-Whelk-O 1 and ChiraSpher. The isomers of 2-butene-1,4-diol can be separated on both chiral columns while the isomers of lafutidine can only be resolved on ChiraSpher column. The influence of different type and amount of mobile phase modifier on the isomers separation was extensively studied. The resolution of cis and trans isomers of 2-butene-1,4-diol was 2.61 on (S,S)-Whelk-O 1 column with hexane-ethanol (97:3, v/v) as the mobile phase. The resolution of lafutidine was 1.89 on ChiraSpher column with hexane-ethanol-THF-diethylamine (92:3:5:0.1, v/v/v/v) as the mobile phase. LC-MS methods were developed to identify the isomer peaks.