Neuron secrete exosomes containing miR-9-5p to promote polarization of M1 microglia in depression.

BACKGROUND: Neuroinflammation is an important component mechanism in the development of depression. Exosomal transfer of MDD-associated microRNAs (miRNAs) from neurons to microglia might exacerbate neuronal cell inflammatory injury. RESULTS: By sequence identification, we found significantly higher miR-9-5p expression levels in serum exosomes from MDD patients than healthy control (HC) subjects. Then, in cultured cell model, we observed that BV2 microglial cells internalized PC12 neuron cell-derived exosomes while successfully transferring miR-9-5p. MiR-9-5p promoted M1 polarization in microglia and led to over releasing of proinflammatory cytokines, such as interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), which exacerbated neurological damage. Furthermore, we identified suppressor of cytokine signaling 2 (SOCS2) as a direct target of miR-9-5p. Overexpression of miR-9-5p suppressed SOCS2 expression and reactivated SOCS2-repressed Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathways. Consistently, we confirmed that adeno-associated virus (AAV)-mediated overexpression of miR-9-5p polarized microglia toward the M1 phenotype and exacerbated depressive symptoms in chronic unpredictable mild stress (CUMS) mouse mode. CONCLUSION: MiR-9-5p was transferred from neurons to microglia in an exosomal way, leading to M1 polarization of microglia and further neuronal injury. The expression and secretion of miR-9-5p might be novel therapeutic targets for MDD.

Abnormalities in FGF family members and their roles in modulating depression-related molecules.

The role of the fibroblast growth factor (FGF) system in depression has received considerable attention in recent years. To understand the role of this system, it is important to identify the specific members of the FGF family that have been implicated and the various mechanisms that they modulated. Here, we review the role of FGFs in depression and integrate evidence from clinical and basic research. These data suggest that changes in the FGF family are involved in depression and possibly in a wider range of psychiatric disorders. We analyse the abnormalities of FGF family members in depression and their roles in modulating depression-related molecules. The role of the FGF family in depression and related disorders needs to be studied in more detail.

Increased NHE1 expression is targeted by specific inhibitor cariporide to sensitize resistant breast cancer cells to doxorubicin in vitro and in vivo.

BACKGROUND: The Na+/H+ exchanger (NHE1) plays a crucial role in cancer cell proliferation and metastasis. However, the mechanism underlying chemotherapeutic resistance in cancer cells has not been completely elucidated. The NHE1 inhibitor cariporide has been demonstrated to inhibit human cancer cell lines. The goal of this study was to provide new sights into improved cancer cell chemosensitivity mediated by cariporide with activation of the apoptosis pathway. METHODS: The NHE1 expression levels were first evaluated using the online database Oncomine and were determined by RT-PCR and western blot in vitro and in vivo. Cell proliferation was assessed In vitro through a CCK-8 assay, and apoptosis was analyzed by flow cytometry. An in vivo analysis was performed in BALB/c nude mice, which were intraperitoneally injected with MCF-7/ADR cells. RESULTS: NHE1 levels were significantly higher in breast cancer tissue than adjacent tissue, as well as in resistant cancer cells compared to sensitive cells. Cariporide induced the apoptosis of MCF-7/ADR cells and was associated with the intracellular accumulation of doxorubicin and G0/G1 cell cycle arrest. Moreover, cariporide decreased MDR1 expression and activated cleaved caspase-3 and caspase-9, promoting caspase-independent apoptosis in vitro. In vivo, cariporide significantly improved doxorubicin sensitivity in a xenograft model, enhancing tumor growth attenuation and diminishing tumor volume. CONCLUSIONS: Our results demonstrate that cariporide significantly facilitates the sensitivity of breast cancer to doxorubicin both in vitro and in vivo. This finding suggests that NHE1 may be a novel adjuvant therapeutic candidate for the treatment of resistant breast cancer.

Heterogeneity of adult masseter muscle satellite cells with cardiomyocyte differentiation potential.

Although resident cardiac stem cells have been reported, regeneration of functional cardiomyocytes (CMs) remains a challenge. The present study identifies an alternative progenitor source for CM regeneration without the need for genetic manipulation or invasive heart biopsy procedures. Unlike limb skeletal muscles, masseter muscles (MM) in the mouse head are developed from Nkx2-5 mesodermal progenitors. Adult masseter muscle satellite cells (MMSCs) display heterogeneity in developmental origin and cell phenotypes. The heterogeneous MMSCs that can be characterized by cell sorting based on stem cell antigen-1 (Sca1) show different lineage potential. While cardiogenic potential is preserved in Sca1+ MMSCs as shown by expression of cardiac progenitor genes (including Nkx2-5), skeletal myogenic capacity is maintained in Sca1- MMSCs with Pax7 expression. Sca1+ MMSC-derived beating cells express cardiac genes and exhibit CM-like morphology. Electrophysiological properties of MMSC-derived CMs are demonstrated by calcium transients and action potentials. These findings show that MMSCs could serve as a novel cell source for cardiomyocyte replacement.

Fibroblast growth factor 22 is a novel modulator of depression through interleukin-1ß.

BACKGROUND AND AIMS: Emerging evidence shows that fibroblast growth factor 22 (FGF22) plays a critical role in the etiology of depression. However, the molecular mechanisms of FGF22 are not fully comprehended. Here, the effect of FGF22 in depression and its relationship with interleukin-1ß (IL-1ß) were investigated in clinical, animal, and cell experiments. METHODS: Serum from depressive patients was collected, and the levels of FGF22 and IL-1ß were analyzed by ELISA. The chronic unpredictable mild stress (CUMS) model was established, and primary hippocampal neuronal cells were cultured to examine changes in FGF22 and IL-1ß levels in rat hippocampus. RESULTS: The results revealed a negative correlation between serum FGF22 levels and serum IL-1ß levels. The expression of IL-1ß in the CUMS rat hippocampus decreased, and the apoptosis of hippocampal cells improved after the injection of lentiviral vector-mediated FGF22 (LV-FGF22). Further tests in primary hippocampal neuronal cells also showed a reduction in IL-1ß and the cell apoptosis rate after treatment with FGF22. CONCLUSION: In conclusion, the results revealed that FGF22 plays a role in alleviating depression, which may be mediated by reduced expression of IL-1ß.

Activation of Sonic hedgehog signal by Purmorphamine, in a mouse model of Parkinson's disease, protects dopaminergic neurons and attenuates inflammatory response by mediating PI3K/AKt signaling pathway.

In Parkinson's disease (PD), microglial activation-mediated neuroinflammation is associated with dopaminergic neurons degeneration in the substantia nigra pars compacta. Previous studies that have investigated this neurodegenerative disease have reported that the Sonic hedgehog (SHH) signaling pathway, through inhibiting the inflammatory processes, exerts a beneficial neuroprotective effect. However, the mechanisms underlying the anti­inflammatory and neuroprotective effects of this signaling pathway remain poorly understood. The present study aimed to further investigate these mechanisms in vitro and in vivo. At first, BV2 microglial cells treated with lipopolysaccharide (LPS) were used to induce an inflammatory response. It was observed that the activation of SHH signaling by Purmorphamine attenuated the LPS­induced inflammatory response, increased the expression of transforming growth factor­ß1 through the phosphatidylinositol 3­kinase (PI3K)/AKT serine/threonine kinase (Akt) intracellular signaling pathway and inhibited nuclear receptor subfamily 4 group A member 2, independently of the PI3K/Akt signaling pathway. Furthermore, the blockade of the PI3K/Akt signaling pathway by intranasal administration of LY294002, significantly reduced the SHH­associated neuroprotective effects on dopaminergic neurons, improved motor functions, and increased the microglial activation and inflammatory response in a mouse model of PD induced using 1­methyl­4­phenyl­1,2,3,6­tetrahydropyridine. In conclusion, the data of the present study reported that anti­inflammatory and neuroprotective effects can be obtained in BV2 microglial cells and in a mouse model of PD by successive activation of the SHH and PI3K/Akt signaling pathways.

PIK3R1 targeting by miR-21 suppresses tumor cell migration and invasion by reducing PI3K/AKT signaling and reversing EMT, and predicts clinical outcome of breast cancer.

We have previously shown that dysregulation of miR-21 functioned as an oncomiR in breast cancer. The aim of the present study was to elucidate the mechanisms by which miR-21 regulate breast tumor migration and invasion. We applied pathway analysis on genome microarray data and target-predicting algorithms for miR-21 target screening, and used luciferase reporting assay to confirm the direct target. Thereafter, we investigated the function of the target gene phosphoinositide-3-kinase, regulatory subunit 1 (α) (PIK3R1), and detected PIK3R1 coding protein (p85α) by immunohistochemistry and miR-21 by RT-qPCR on 320 archival paraffin-embedded tissues of breast cancer to evaluate the correlation of their expression with prognosis. First, we found that PIK3R1 suppressed growth, invasiveness, and metastatic properties of breast cancer cells. Next, we identified the PIK3R1 as a direct target of miR-21 and showed that it was negatively regulated by miR-21. Furthermore, we demonstrated that p85α overexpression phenocopied the suppression effects of antimiR-21 on breast cancer cell growth, migration and invasion, indicating its tumor suppressor role in breast cancer. On the contrary, PIK3R1 knockdown abrogated antimiR­21-induced effect on breast cancer cells. Notably, antimiR-21 induction increased p85α, accompanied by decreased p-AKT level. Besides, antimiR-21/PIK3R1-induced suppression of invasiveness in breast cancer cells was mediated by reversing epithelial-mesenchymal transition (EMT). p85α downregulation was found in 25 (7.8%) of the 320 breast cancer patients, and was associated with inferior 5-year disease-free survival (DFS) and overall survival (OS). Taken together, we provide novel evidence that miR-21 knockdown suppresses cell growth, migration and invasion partly by inhibiting PI3K/AKT activation via direct targeting PIK3R1 and reversing EMT in breast cancer. p85α downregulation defined a specific subgroup of breast cancer with shorter 5-year DFS and OS, which may require more aggressive treatment.

Development, validation, and application of a liquid chromatography-tandem mass spectrometry method for the determination of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol in human hair.

The tobacco-specific nitrosamine metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is a valuable biomarker for human exposure to the carcinogenic nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in tobacco and tobacco smoke. In this work, an efficient and sensitive method for the analysis of NNAL in human hair was developed and validated. The hair sample was extracted by NaOH solution digestion, purified by C(18) solid-phase extraction (SPE) and molecularly imprinted solid-phase extraction, further enriched by reverse-phase ultrasound-assisted dispersive liquid-liquid microextraction (USA-DLLME) into 1.0 % aqueous formic acid, and finally analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry. Good linearity was obtained in the range of 0.24-10.0 pg/mg hair with a correlation coefficient of 0.9982, when 150 mg hair was analyzed. The limit of detection and lower limit of quantification were 0.08 and 0.24 pg/mg hair, respectively. Accuracies determined from hair samples spiked with three different levels of NNAL ranged between 87.3 and 107.7 %. Intra- and inter-day relative standard deviations varied from 4.1 to 8.5 % and from 6.9 to 11.3 %, respectively. Under the optimized conditions, an enrichment factor of 20 was obtained. Finally, the developed method was applied for the analysis of NNAL in smokers' hair. The proposed sample preparation procedure combining selectivity of two-step SPE and enrichment of DLLME significantly improves the purification and enrichment of the analyte and should be useful to analyze NNAL in hair samples for cancer risk evaluation and cancer prevention in relation to exposure to the tobacco-specific carcinogen NNK.

[Effect of triptolide on sensitivity of K562/A02 cell line to adriamycin].

This study was aimed to evaluate the effect of triptolide (TPL) on the reversal of multidrug resistance in K562/A02 cell line. The sensitivity of K562 and K562/A02 to adriamycin (ADM) and reversal of drug resistance were determined with MTT method. The concentration of intracellular ADM and P-glycoprotein expression were detected by flow cytometry. Luciferase reporter gene assay was used to detect the transcriptional activity of MDR1 promoter. The results showed that TPL significantly decreased the resistance degree of K562/A02 cells, inhibited P-glycoprotein expression (mean fluorescent intensity decreased from 123 ± 13 to 39 ± 13) and increased the intracellular concentration of ADM (mean fluorescent intensity increased from 18 ± 5 to 34 ± 6) in K562/A02 cells. Luciferase reporter gene assay demonstrated that TPL inhibited the transcriptional activity of MDR1 promoter by 75%. It is concluded that TPL may effectively reverse the multidrug resistance in K562/A02 cells via modulating P-glycoprotein expression and increasing intracellular ADM accumulation.

Matrine inhibits disturbed flow-enhanced migration via downregulation of ERK1/2-MLCK signaling vascular smooth muscle cells.

BACKGROUND: To investigate the effects of matrine on the vascular smooth muscle cell (VSMC) migration modulated by disturbed flow and their underlying molecular mechanisms in vitro. METHODS: Isolated rat aortic VSMCs were grown to confluence on 20- × 80-mm fibronectin-coated glass cover slides, and then, denuded zones were made at the position calculated to be the oscillating flow-reattachment zone and also in the downstream laminar flow region. VSMCs were treated with different doses of matrine (0, 10, 20, 30, and 40 mg/L), or PD98059 (30 µM), ML-7 (10 µM) combined with matrine (40 mg/L) for 30 minutes before and during the experiments. Then, the wounded monolayers were kept under static conditions or were subjected to laminar or disturbed flow for 21 hours or 10 hours. The VSMC migration was assessed by microscopic images. The extracellular signal-regulated kinase 1/2 (ERK1/2) and myosin light chain kinase (MLCK) proteins were determined by Western blot. RESULTS: Disturbed flow significantly increased phosphorylation of ERK1/2. Selective inhibition of ERK1/2 phosphorylation by inhibitor PD98059 and matrine significantly suppressed VSMC migration under disturbed flow. Disturbed flow significantly enhanced phosphorylation of MLCK, whereas both matrine and PD98059 inhibited the phosphorylation of MLCK under disturbed flow. The complete inhibition of MLCK phosphorylation using the selective MLCK inhibitor ML-7 significantly inhibited VSMC migration under disturbed flow. CONCLUSION: Matrine inhibits VSMC migration under disturbed flow, in part, by downregulation of ERK1/2-MLCK signaling pathway.

[Mechanisms of preventive effect of tetrandrine on acquired multidrug resistance in K562 cells].

This study was purposed to explore the mechanisms of preventive effect of tetrandrine (TTD) on doxorubicin (ADM)-induced multidrug resistance (MDR) in human leukemia cell line K562 from two aspects of the transcription control of MDR1 gene and cell apoptosis. The experiment was divided into 3 groups: group I-blank control; group II-ADM-induced drug-resistance; group III-ADM-induced drug-resistance after pretreatment with TTD. Reverse transcription-PCR (RT-PCR) was used to detect the mRNA expression levels of c-Jun, YB-1 and Survivin genes. Western blot was used to determine the nuclear protein expression levels of c-Jun and YB-1. Flow cytometry was used to assay the apoptosis of cells. The results showed that as compared with group I, the expression levels of c-Jun mRNA and nuclear protein decreased (p < 0.05), as well as the expression levels of YB-1 mRNA and nuclear protein increased in group II (p < 0.05). However, the expression of Survivin mRNA had no change (p > 0.05); the apoptosis rate of cells was 8.31%. As compared with group II, the expression levels of c-Jun mRNA and nuclear protein increased (p < 0.05), expression levels of YB-1 mRNA and nuclear protein as well as Survivin mRNA decreased in group III (p < 0.05). The apoptosis of cells was 97.2%. It is concluded that TTD can inhibit the expression of YB-1 and up-regulate the expression of c-Jun, thus inhibit the expression of MDR1 gene. TTD can also inhibit the expression of Survivin and increase the apoptosis of cells induced by ADM.

A rapid and sensitive liquid chromatography-tandem mass spectrometry method for determination of olopatadine concentration in human plasma.

A sensitive and rapid method based on liquid chromatography- tandem mass spectrometry (MS-MS) was developed for the determination of olopatadine in human plasma. Sample preparations were carried out by protein precipitation with the addition of acetonitrile followed by liquid-liquid extraction with ethyl acetate/dichloromethane after internal standard (IS, amitriptyline) spiked. After evaporation to dryness, the resultant residue was reconstituted in mobile phase. Separation of olopatadine and IS from the interferences was achieved on a C(18) column followed by MS-MS detection. The analytes were monitored in the positive ionization mode with a TurboIonspray source. Multiple reaction monitoring using the transition of m/z 338 → 165 and m/z 278 → 91 was performed to quantify olopatadine and IS, respectively. The method had a total chromatographic run time of 3.5 min and linear calibration curves over the concentration range of 0.2-100 ng/mL. The lower limit of quantification was 0.2 ng/mL. For each QC concentration level the intra- and interday precisions were less than 11.4%, and relative errors ranged between -6.40% and 9.26%. The validated method was successfully applied to the quantification of olopatadine concentration in human plasma after administration of olopatadine at an oral dose of 5 mg in order to evaluate the pharmacokinetics.

Efficacy of intraoperative GeneSearch Breast Lymph Node (BLN) Assay for breast cancer metastasis detection in sentinel lymph node in Chinese patients.

UNLABELLED: Although intraoperative assessment of the sentinel lymph node (SLN) is useful, it has not gained popularity in China as it involves a heavy workload for pathologists. We conducted a prospective clinical feasibility study of the GeneSearch Breast Lymph Node (BLN) Assay performed in 158 SLNs from 97 patients by comparison with postoperative permanent section histopathology, to validate its potential usefulness in China. Every SLN was cut into alternating 1.5 to 3.0 mm slabs. The BLN assay processed 50% of the fresh alternating slabs to detect the presence of cytokeratin 19 and mammaglobin mRNA. Assay results were compared with those for permanent section histopathology and intraoperative imprint cytology. Slides for imprint cytology were prepared from the BLN assay node tissue before it was processed. Full axillary lymph node (ALN) dissections were performed on some patients after a SLN biopsy. The BLN assay was successfully performed on 158 SLNs from 97 patients. Overall performance of the BLN assay compared with permanent section histopathology was sensitivity 83.9% (26/31), specificity 95.5% (63/66), positive predictive value 89.7% (26/29), negative predictive value 92.6% (63/68), and overall agreement 91.8% (89/97). The BLN assay detected about 25% more metastases than imprint cytology. Moreover, the BLN assay correctly identified most of the additional non-sentinel ALNs metastases (P = 0.005). Our results from a large series of Chinese patients with breast cancer indicate that the BLN assay may be a viable alternative for the standard intraoperative procedures used for metastases detection, especially in early stage breast cancer patients. Name of the trial register: GeneSearch Breast Lymph Node (BLN) Assay China Registration Study. CLINICAL TRIAL REGISTRATION NUMBER: NCT00869674.

Inhibition of lung cancer cell proliferation by CD40 signaling through tumor necrosis factor I.

BACKGROUND AND OBJECTIVE: CD40 signaling induces growth inhibition in some tumor cells in vitro, but the precise molecular mechanism remains unclear. This study was to investigate the biological effects and mechanisms of CD40 stimulation on proliferation of lung cancer cell lines NCI-H460 and A549, changes in tumor necrosis factor receptors (TNFRs) and membrane tumor necrosis factor alpha (mTNF-alpha). METHODS: The expression of CD40 on the cell surface, and changes in TNFR and mTNF-alpha expression after CD40 stimulation were detected by the immunofluorescence technique and flow cytometry. Changes in protein contents of TNFR as well as mTNF-alpha expression after CD40 stimulation were measured by western blot. The cell proliferation rate was determined by MTT assay. The content of soluble TNF-alpha(sTNF-alpha) in the supernatant of lung cancer cells was measured by ELISA assay. RESULTS: The expression rates of CD40 in NCI-H460 and A549 were (89.0 +/- 3.2)% and (62.2 +/- 4.5)%, respectively. After 48 h of CD40 stimulation, the expression rates of TNFRI in NCI-H460 and A549 became significantly higher [(36.2 +/- 4.6)% and (38.5 +/- 5.9)%] than those in the corresponding control cells [(15.2 +/- 3.1)% and (7.2 +/- 1.9)%] (p < 0.05); while the expression rates of TNFRII were significantly lower than those in the control cells [(18.0 +/- 1.6)% and (5.8 +/- 1.2)% vs. (58.1 +/- 3.6)% and (38.8 +/- 4.3)%] (p < 0.05); the expression rates of mTNF-alpha were decreased in the two cell lines [(8.7 +/- 1.1)% and (7.0 +/- 0.9)%] as compared to those in control cells [(15.0 +/- 2.1)% and (26.5 +/- 3.2)%] (p < 0.05). The level of TNFRI protein was elevated with the downregulation of TNFRII protein in NCI-H460 and A549. The level of mTNF-alpha protein remained unchanged in the two cell lines. TNF-alpha was not detectable in the supernatant of lung cancer cells. Moreover, cell proliferation of NCI-H460 and A549 were inhibited after CD40 stimulation (p < 0.05), but the inhibition effect disappeared after blocking TNFRI. Blocking of TNF-alpha inhibited cell proliferation of the two cell lines (p < 0.05), but a synergistic effect was not observed after simultaneous stimulation with CD40. CONCLUSION: CD40 signaling inhibits the proliferation of CD40-positive lung cancer cells through mTNF-alpha/TNFRI in vitro.

[Spectroscopy study of binding mechanisms and molecular recognition of methamidophos-specific moleculary imprinted polymer].

A new methamidophos-specific molecularly imprinted polymer (MIP) was synthesized based on non-covalent interaction. The complexes formed between MAP and MAA were evaluated by 1H NMR, FTIR and UV spectrometry. The MAP-MAA complexes of 1 : 2 mole ratio were obtained by cooperative hydrogen bonding and the complexes possessed better stabilization (K = 2.894 x 10(6) L2 x mol(-2). The Infrared spectrometry differences of the MIPs before and after saturated with MAP further indicated that there were carboxyl functional groups in the MIP, which could interact with the template by cooperative hydrogen bonding specifically.

[Spectroscopy and XPS studies on molecular recognition of a molecularly imprinted cotinine-specific polymer].

In the present study, molecular imprinting technique was used to develop a method based on noncovalent interaction for the systhesis of a cotinine-specific polymer. The molecular recognition characteristics of the template polymer were evaluated by UV, IR, XPS and 1H NMR. The results indicated that the interactions should be cooperative hydrogen bonds produced by self-assembling of the template and the monomer. The stoichiometric mole ratio of COT-MAA complex is 1 : 2. Furthermore, nitrogen atom of the pyridine ring and oxygen atom of the lactam group in cotinine molecular are hydrogen-bond acceptors, being the predominant binding sites interacting with the functional monomer.

[Determination of orlistat in health food for controlling body weight by high performance liquid chromatography/electrospray spectrometry].

OBJECTIVE: To establish a method of determining orlistat in health food by on line HPLC-UV-ESI/MS. METHODS: The separation was completed on an analytical Spherigel C8 column (5 microm, 200 mm x 4.6 mm) with acetonitrile (0.1% formic acid) : water (0.1% formic acid) = 80 : 20 as mobile phase, the detection wavelength was 2003 mm. RESULTS: Good linearity between peak areas and concentrations was obtained during rag of 0.3 - 0.6 mg/ml. CONCLUSION: The method is simple and can be used to determine orlistat in the health food for controlling body weight accurately.

A new molecularly imprinted polymer for selective extraction of cotinine from urine samples by solid-phase extraction.

Cotinine, the main metabolite of nicotine in human body, is widely used as a biomarker for assessment of direct or passive exposure to tobacco smoke. A method for molecularly imprinted solid-phase extraction (MISPE) of cotinine from human urine has been investigated. The molecularly imprinted polymer (MIP) with good selectivity and affinity for cotinine was synthesized using cotinine as the template molecule, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. The imprinted polymer was evaluated for use as a SPE sorbent, in tests with aqueous standards, by comparing recovery data obtained using the imprinted form of the polymer and a non-imprinted form (NIP). Extraction from the aqueous solutions resulted in more than 80% recovery. A range of linearity for cotinine between 0.05 and 5 microg mL-1 was obtained by loading 1 mL blank urine samples spiked with cotinine at different concentrations in acetate buffer of pH 9.0, and by using double basic washing and acidic elution. The intra-day coefficient of variation (CV) was below 7% and inter-day CV was below 10%. This investigation has provided a reliable MISPE-HPLC method for determination of cotinine in human urine from both active smokers and passive smokers.

[Spectroscopy study of molecular recognition of a molecular imprinted monocrotophos-specific polymer].

In the present study, molecular imprinting was used to develop a method based on noncovalent interaction for the synthesis of a monocrotophos-specific polymer. The selective binding characteristics of the template polymer were evaluated by 1H NMR and ultraviolet spectrometry. The polymer obtained was found to interact specifically with monocrotophos by cooperative hydrogen bonding. The infrared spectrometry of the polymer further indicated that there were some functional groups in the moleculary imprinted polymer which could interact on the template.