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1.
Hepatology ; 78(5): 1337-1351, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37021797

ABSTRACT

BACKGROUND AND AIMS: Paucity of intrahepatic bile ducts (BDs) is caused by various etiologies and often leads to cholestatic liver disease. For example, in patients with Alagille syndrome (ALGS), which is a genetic disease primarily caused by mutations in jagged 1 ( JAG1) , BD paucity often results in severe cholestasis and liver damage. However, no mechanism-based therapy exists to restore the biliary system in ALGS or other diseases associated with BD paucity. Based on previous genetic observations, we investigated whether postnatal knockdown of the glycosyltransferase gene protein O -glucosyltransferase 1 ( Poglut1) can improve the ALGS liver phenotypes in several mouse models generated by removing one copy of Jag1 in the germline with or without reducing the gene dosage of sex-determining region Y-box 9 in the liver. APPROACH AND RESULTS: Using an ASO established in this study, we show that reducing Poglut1 levels in postnatal livers of ALGS mouse models with moderate to profound biliary abnormalities can significantly improve BD development and biliary tree formation. Importantly, ASO injections prevent liver damage in these models without adverse effects. Furthermore, ASO-mediated Poglut1 knockdown improves biliary tree formation in a different mouse model with no Jag1 mutations. Cell-based signaling assays indicate that reducing POGLUT1 levels or mutating POGLUT1 modification sites on JAG1 increases JAG1 protein level and JAG1-mediated signaling, suggesting a likely mechanism for the observed in vivo rescue. CONCLUSIONS: Our preclinical studies establish ASO-mediated POGLUT1 knockdown as a potential therapeutic strategy for ALGS liver disease and possibly other diseases associated with BD paucity.


Subject(s)
Alagille Syndrome , Glycosyltransferases , Liver , Oligonucleotides, Antisense , Animals , Mice , Alagille Syndrome/genetics , Alagille Syndrome/metabolism , Alagille Syndrome/pathology , Bile Ducts, Intrahepatic/metabolism , Bile Ducts, Intrahepatic/pathology , Calcium-Binding Proteins/genetics , Cholestasis/genetics , Cholestasis/metabolism , Gene Silencing , Glucosyltransferases/genetics , Glucosyltransferases/metabolism , Glycosyltransferases/genetics , Glycosyltransferases/metabolism , Intercellular Signaling Peptides and Proteins/genetics , Jagged-1 Protein/genetics , Jagged-1 Protein/metabolism , Liver/metabolism , Liver/pathology , Membrane Proteins/genetics , Oligonucleotides, Antisense/genetics , Oligonucleotides, Antisense/metabolism , Phenotype , Serrate-Jagged Proteins/genetics , Serrate-Jagged Proteins/metabolism
2.
J Microbiol ; 60(6): 649-656, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35489019

ABSTRACT

Inflammatory responses involve the action of inflammatory mediators that are necessary for the clearance of invading bacterial pathogens. However, excessive production of inflammatory mediators can damage tissues, thereby impairing bacterial clearance. Here, we examined the effects of Weigela florida on the expression of inflammatory cytokines induced by Pseudomonas aeruginosa or Staphylococcus aureus infection in macrophages. The results showed that pre-treatment with W. florida markedly downregulated the bacterial infection-mediated expression of cytokines. Additionally, post-treatment also triggered anti-inflammatory effects in cells infected with S. aureus to a greater extent than in those infected with P. aeruginosa. Bacterial infection activated inflammation-associated AKT (Thr308 and Ser473)/NF-κB and MAPK (p38, JNK, and ERK) signaling pathways, whereas W. florida treatment typically inhibited the phosphorylation of AKT/NF-κB and p38/JNK, supporting the anti-inflammatory effects of W. florida. The present results suggest that W. florida decreases the infection-mediated expression of inflammatory mediators by inhibiting the AKT/NF-κB and MAPK signaling pathways, implying that it may have potential use as an inhibitory agent of excessive inflammatory responses.


Subject(s)
Inflammation Mediators , Staphylococcal Infections , Anti-Inflammatory Agents/pharmacology , Cytokines/metabolism , Humans , Inflammation Mediators/metabolism , Inflammation Mediators/pharmacology , NF-kappa B/genetics , NF-kappa B/metabolism , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Pseudomonas aeruginosa/metabolism , Staphylococcus aureus
3.
Insights Imaging ; 13(1): 80, 2022 Apr 25.
Article in English | MEDLINE | ID: mdl-35467253

ABSTRACT

Endometrial carcinoma is the most common gynaecological cancer in developed countries. Most cases are low-volume/low-grade tumour at presentation; however, high-grade subtypes may present with locally advanced disease with higher propensity for spread outside of the pelvis. MRI has a role in local staging of the tumour and helping the clinicians in treatment decision making. This pictorial essay gives examples of endometrial carcinoma at different stages with histological correlation. It also explores the potential limitations and pitfalls of imaging in this context.

4.
Science ; 372(6538)2021 04 09.
Article in English | MEDLINE | ID: mdl-33833095

ABSTRACT

During multicellular development, spatial position and lineage history play powerful roles in controlling cell fate decisions. Using a serine integrase-based recording system, we engineered cells to record lineage information in a format that can be read out in situ. The system, termed integrase-editable memory by engineered mutagenesis with optical in situ readout (intMEMOIR), allowed in situ reconstruction of lineage relationships in cultured mouse cells and flies. intMEMOIR uses an array of independent three-state genetic memory elements that can recombine stochastically and irreversibly, allowing up to 59,049 distinct digital states. It reconstructed lineage trees in stem cells and enabled simultaneous analysis of single-cell clonal history, spatial position, and gene expression in Drosophila brain sections. These results establish a foundation for microscopy-readable lineage recording and analysis in diverse systems.


Subject(s)
Cell Lineage , Gene Expression , Mouse Embryonic Stem Cells/cytology , Neurons/cytology , Single-Cell Analysis , Animals , Brain/cytology , Cell Line , Clone Cells/cytology , Drosophila melanogaster/cytology , Drosophila melanogaster/embryology , Gene Expression Profiling , Heat-Shock Response , In Situ Hybridization, Fluorescence , Integrases/metabolism , Mice , Mutagenesis , Spatial Analysis , Time-Lapse Imaging , Transcription, Genetic
5.
Am J Respir Cell Mol Biol ; 60(5): 532-540, 2019 05.
Article in English | MEDLINE | ID: mdl-30365340

ABSTRACT

Bitter taste receptor (TAS2R) agonists dilate airways by receptor-dependent smooth muscle relaxation. Besides their coupling to relaxation, we have found that human airway smooth muscle (HASM) cell TAS2Rs activate (phosphorylate) extracellular signal-related kinase 1/2 (ERK1/2), but the cellular effects are not known. In the present study, we show in HASM cells that TAS2R agonists initially stimulate phosphorylated ERK1/2 (pERK1/2) but by 24 hours cause a marked (50-70%) downregulation of pERK1/2 without a change in total ERK1/2. It was hypothesized that TAS2R agonists suppress cell growth through this pERK1/2 downregulation. Agonist-dependent inhibition of cell proliferation was indeed found in HASM cells derived from normal and asthmatic human lungs, as well as in an immortalized HASM cell line. pERK1/2 downregulation was linked to downregulation of the upstream kinase MEK1/2 (mitogen-activated protein kinase/extracellular signal-regulated kinase). Various structurally diverse TAS2R agonists evoked a range of inhibition of HASM proliferation, the magnitude of which directly correlated with the downregulation of pERK1/2 (R2 = 0.86). Some TAS2R agonists were as effective as pharmacological inhibitors of Raf1 and MEK1/2 in suppressing growth. siRNA silencing of TAS2Rs (subtypes 10, 14, and 31) ablated the pERK1/2 and growth-inhibitory effects of TAS2R agonists. These phenotypes were attenuated by inhibiting the TAS2R G protein Gαi and by knocking down ß-arrestin 1/2, indicating a dual pathway, although there may be additional mechanisms involved in this HASM TAS2R multidimensional signaling. Thus, TAS2R agonist structure can be manipulated to maintain the relaxation response and can be biased toward suppression of HASM growth. The latter response is of potential therapeutic benefit in asthma, in which an increase in smooth muscle mass contributes to airway obstruction.


Subject(s)
Bronchodilator Agents/pharmacology , Gene Expression Regulation/drug effects , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 3/genetics , Myocytes, Smooth Muscle/drug effects , Receptors, G-Protein-Coupled/genetics , Asthma/drug therapy , Asthma/genetics , Asthma/metabolism , Asthma/pathology , Bronchi/drug effects , Bronchi/metabolism , Bronchi/pathology , Calcium/metabolism , Case-Control Studies , Cell Line , Cell Proliferation/drug effects , Emodin/analogs & derivatives , Emodin/pharmacology , Famotidine/pharmacology , Humans , Ion Transport/drug effects , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/antagonists & inhibitors , Mitogen-Activated Protein Kinase 3/metabolism , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Papaverine/pharmacology , Phosphorylation/drug effects , Primary Cell Culture , Receptors, G-Protein-Coupled/metabolism , Signal Transduction , beta-Arrestin 1/genetics , beta-Arrestin 1/metabolism , beta-Arrestin 2/genetics , beta-Arrestin 2/metabolism
6.
FASEB J ; 32(7): 3680-3688, 2018 07.
Article in English | MEDLINE | ID: mdl-29455573

ABSTRACT

ß2-Adrenergic receptors (ß2ARs) desensitize during continuous agonist activation, which manifests clinically as tachyphylaxis. ß-Agonist desensitization of ß2ARs in human airway smooth muscle (HASM) cells is recognized in the treatment of asthma and may be related to poor outcomes. Rapid events in desensitization include receptor phosphorylation and internalization, but mechanisms responsible for the decrease in receptor protein after prolonged agonist exposure (down-regulation) are ill defined. The microRNA (miRNA) let-7f regulates ß2AR expression by translational repression. In cultured HASM cells from nonasthmatic and asthmatic lungs, 18 h of ß-agonist exposure increased let-7f by 2-3-fold, concomitant with a ∼90% decrease in ß2ARs. Inhibition of let-7f attenuated this down-regulation response by ∼50%. The let-7f increase was found to be cAMP/PKA-dependent. The mechanism of the let-7f increase was found by chromatin immunoprecipitation to be from activated cAMP response element-binding protein (CREB) binding to the let-7f promoter, thereby increasing let-7f expression. Knockdown of CREB attenuated agonist-promoted ß2AR down-regulation by ∼50%. Thus, ß2AR down-regulation occurs as a result of not only internalized receptor degradation but also a novel cAMP/PKA/CREB-mediated increase in let-7f, which causes enhanced repression of the ß2AR gene, adrenoreceptor ß2 ( ADRB2) translation and represents ∼50% of the net loss of receptors observed after prolonged agonist exposure. This mechanism is apparent in asthmatic HASM cells, indicating relevance in a disease model.-Kim, D., Cho, S., Woo, J. A., Liggett, S. B. A CREB-mediated increase in miRNA let-7f during prolonged ß-agonist exposure: a novel mechanism of ß2-adrenergic receptor down-regulation in airway smooth muscle.


Subject(s)
Adrenergic beta-2 Receptor Agonists/pharmacology , Asthma/metabolism , Cyclic AMP Response Element-Binding Protein/metabolism , MicroRNAs/genetics , Muscle, Smooth/metabolism , Receptors, Adrenergic, beta-2/genetics , Cell Line , Down-Regulation , Humans , Lung/cytology , Lung/drug effects , Lung/metabolism , MicroRNAs/metabolism , Muscle, Smooth/drug effects , Receptors, Adrenergic, beta-2/metabolism
7.
Rice (N Y) ; 11(1): 3, 2018 Jan 10.
Article in English | MEDLINE | ID: mdl-29322324

ABSTRACT

BACKGROUND: Bakanae or foot rot disease is a prominent disease of rice caused by Gibberella fujikuroi. This disease may infect rice plants from the pre-emergence stage to the mature stage. In recent years, raising rice seedlings in seed boxes for mechanical transplanting has increased the incidence of many seedling diseases; only a few rice varieties have been reported to exhibit resistance to bakanae disease. In this study, we attempted to identify quantitative trait loci (QTLs) conferring bakanae disease resistance from the highly resistant japonica variety Wonseadaesoo. RESULTS: A primary QTL study using the genotypes/phenotypes of the recombinant inbred lines (RILs) indicated that the locus qBK1 WD conferring resistance to bakanae disease from Wonseadaesoo was located in a 1.59 Mb interval delimited on the physical map between chr01_13542347 (13.54 Mb) and chr01_15132528 (15.13 Mb). The log of odds (LOD) score of qBK1 WD was 8.29, accounting for 20.2% of the total phenotypic variation. We further identified a gene pyramiding effect of two QTLs, qBK WD and previously developed qBK1. The mean proportion of healthy plant for 31 F4 RILs that had no resistance genes was 35.3%, which was similar to that of the susceptible check variety Ilpum. The proportion of healthy plants for the lines with only qBK WD or qBK1 was 66.1% and 55.5%, respectively, which was significantly higher than that of the lines without resistance genes and that of Ilpum. The mean proportion of the healthy plant for 15 F4 RILs harboring both qBK WD and qBK1 was 80.2%, which was significantly higher than that of the lines with only qBK WD or qBK1. CONCLUSION: Introducing qBK WD or pyramiding the QTLs qBK WD and qBK1 could provide effective tools for breeding rice with bakanae disease resistance. To our knowledge, this is the first report on a gene pyramiding effect that provides higher resistance against bakanae disease.

8.
Article in English | MEDLINE | ID: mdl-29136552

ABSTRACT

Over the past few decades, honey products have been polluted by different contaminants, such as pesticides, which are widely applied in agriculture. In this work, a modified EN - quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method was developed for the simultaneous quantification of pesticide residues, including cymiazole, fipronil, coumaphos, fluvalinate, amitraz, and its metabolite 2,4-dimethylaniline (2,4-DMA), in four types of honey (acacia, wild, chestnut, and manuka) and royal jelly. Samples were buffered with 0.2M dibasic sodium phosphate (pH 9), and subsequently, acetonitrile was employed as the extraction solvent. A combination of primary secondary amine (PSA) and C18 sorbents was used for purification prior to liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI+/MS-MS) analysis. The estimated linearity measured at six concentration levels presented good correlation coefficients (R2)≥0.99. The recovery, calculated from three different spiking levels, was 62.06-108.79% in honey and 67.58-106.34% in royal jelly, with an RSD<12% for all the tested compounds. The matrix effect was also evaluated, and most of the analytes presented signal enhancement. The limits of quantification (LOQ) ranged between 0.001 and 0.005mg/kg in various samples. These are considerably lower than the maximum residue limits (MRL) set by various regulatory authorities. A total of 43 market (domestic and imported) samples were assayed for method application. Among the tested samples, three samples were tested positive (i.e. detected and quantified) only for cymiazole residues. The residues in the rest of the samples were detected but not quantified. We concluded that the protocol developed in this work is simple and versatile for the routine quantification of cymiazole, 2,4-DMA, fipronil, coumaphos, amitraz, and fluvalinate in various types of honey and royal jelly.


Subject(s)
Chromatography, Liquid/methods , Fatty Acids/chemistry , Honey/analysis , Pesticide Residues/analysis , Tandem Mass Spectrometry/methods , Coumaphos , Limit of Detection , Linear Models , Nitriles , Pesticide Residues/metabolism , Pyrazoles , Pyrethrins , Reproducibility of Results , Thiazoles , Toluidines
9.
Article in English | MEDLINE | ID: mdl-28918317

ABSTRACT

Herein, we developed a simple analytical procedure for the quantitation of bithionol residues in animal-derived food products such as porcine muscle, eggs, milk, eel, flatfish, and shrimp using a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method coupled with liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI+/MS-MS). Samples were extracted with 0.1% solution of formic acid in acetonitrile and the extract was purified using a C18 sorbent. Separation was performed on a Waters XBridge™ C18 reversed-phase analytical column using 0.1% solution of formic acid/acetonitrile as the mobile phase. Six-point matrix-matched calibration indicated good linearity, with the calculated coefficients of determination (R2) being≥0.9813. Intra- and inter-day recoveries (determined at spiking levels equivalent to 1×and 2×the limit of quantitation (0.25µg/kg)) ranged between 80.0 and 94.0%, with the corresponding relative standard deviations (RSDs) being≤8.2%. The developed experimental protocol was applied to different samples purchased from local markets in Seoul, which were tested negative for bithionol residues. In conclusion, the proposed method proved to be versatile and precise, being ideally suited for the routine detection of bithionol residues in animal-derived food products with various protein and fat contents.


Subject(s)
Bithionol/analysis , Chromatography, Liquid/methods , Drug Residues/analysis , Food Contamination/analysis , Tandem Mass Spectrometry/methods , Animals , Bithionol/chemistry , Bithionol/isolation & purification , Chemical Fractionation/methods , Drug Residues/chemistry , Drug Residues/isolation & purification , Eggs/analysis , Limit of Detection , Linear Models , Milk/chemistry , Reproducibility of Results , Seafood/analysis
10.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1065-1066: 29-34, 2017 Oct 15.
Article in English | MEDLINE | ID: mdl-28946122

ABSTRACT

In this study, a simple analytical approach has been developed and validated for the determination of bupivacaine hydrochloride and isoflupredone acetate residues in porcine muscle, beef, milk, egg, shrimp, flatfish, and eel using liquid chromatography-tandem mass spectrometry (LC-MS/MS). A 0.1% solution of acetic acid in acetonitrile combined with n-hexane was used for deproteinization and defatting of all tested matrices and the target drugs were well separated on a Waters Xbridge™ C18 analytical column using a mobile phase consisting of 0.1% acetic acid (A) and 0.1% solution of acetic acid in methanol (B). The linearity estimated from six-point matrix-matched calibrations was good, with coefficients of determination ≥0.9873. The limits of quantification (LOQs) for bupivacaine hydrochloride and isoflupredone acetate were 1 and 2ngg-1, respectively. Recovery percentages in the ranges of 72.51-112.39% (bupivacaine hydrochloride) and 72.58-114.56% (isoflupredone acetate) were obtained from three different fortification concentrations with relative standard deviations (RSDs) of <15.14%. All samples for the experimental work and method application were collected from the local markets in Seoul, Republic of Korea, and none of them tested positive for the target drugs. In conclusion, a simple method using a 0.1% solution of acetic acid in acetonitrile and n-hexane followed by LC-MS/MS could effectively extract bupivacaine hydrochloride and isoflupredone acetate from porcine muscle, beef, milk, egg, shrimp, flatfish, and eel samples.


Subject(s)
Bupivacaine/analysis , Drug Residues/analysis , Fluprednisolone/analogs & derivatives , Milk/chemistry , Red Meat/analysis , Seafood/analysis , Animals , Chromatography, Liquid/methods , Eels , Flatfishes , Fluprednisolone/analysis , Linear Models , Penaeidae , Reproducibility of Results , Sensitivity and Specificity , Swine , Tandem Mass Spectrometry/methods
11.
Oncol Lett ; 14(2): 2410-2416, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28789457

ABSTRACT

Epithelial-mesenchymal transition (EMT) is a notable mechanism underlying cancer cell metastasis. Transforming growth factor ß1 (TGF-ß1) has been used to induce EMT; however, there is a lack of information regarding the role of TGF-ß1 in mesenchymal-epithelial transition (MET). In the present study, EMT was induced in A549 lung cancer cells using TGF-ß1 (TGF-ß1-treated group) and MET was induced sequentially from the TGF-ß1-treated group by removing the TGF-ß1 (MET/return group). Untreated A549 lung cancer cells were used as a control. Characteristic features, including cancer stem cell markers [cluster of differentiation (CD)24, CD44 and CD133], cell proliferation and migration and diverse intracellular mechanisms, were observed in all groups. Using western blot analysis, the TGF-ß1-treated group demonstrated increased vimentin and reduced E-cadherin expression, whereas the MET/return group demonstrated the opposite trend. Among cancer stem cell markers, the population of CD24low cells was reduced in the TGF-ß1-treated group. Furthermore, the G2/M phase cell cycle population, cisplatin-sensitivity, and cell proliferation and migration ability were increased in the TGF-ß1-treated group. These features were unaltered in the MET/return group when compared to the TGF-ß1-treated group. Immunoblotting revealed an increase in the levels of SMAD3, phosphorylated SMAD3, phosphorylated extracellular signal-regulated kinase and caspase-3, and a decrease in active caspase-3 levels in the TGF-ß1-treated group. Increased caspase-3 and reduced active caspase-3 levels were observed in the MET/return group, similar to those in the TGF-ß1-treated group; however, levels of other signalling proteins were unchanged compared with the control group. EMT induced by TGF-ß1 was not preserved; however, stemness-associated properties (CD24 expression, caspase-3 expression, cell proliferation and cisplatin-resistance) were sustained following removal of TGF-ß1.

12.
BJR Case Rep ; 3(2): 20160107, 2017.
Article in English | MEDLINE | ID: mdl-30363301

ABSTRACT

Adrenal haemorrhage is a rare condition that has the potential to cause life-threatening adrenal insufficiency, especially if it affects both the adrenal glands. The difficulty in diagnosing adrenal haemorrhages lies in the non-specific clinical presentation including hypotension and abdominal pain. The following case report demonstrates the possible clinical presentations of non-traumatic adrenal haemorrhages and the method of diagnosing and treating adrenal insufficiency. In a medical era where overdiagnosis and "incidentalomas" are becoming more prevalent, this case nicely demonstrates the fortunate use of imaging to detect a potentially life-threatening condition.

13.
Biomed Chromatogr ; 31(6)2017 Jun.
Article in English | MEDLINE | ID: mdl-27862109

ABSTRACT

In this study, an analytical method was developed for quantification of residues of the anthelmintic drug phenothiazine (PTZ) in pork muscle using liquid chromatography-tandem mass spectrometry. Muscles were extracted using 0.2% formic acid and 10 mm ammonium formate in acetonitrile, defatted and purified using n-hexane. The drug was well separated on a Waters XBridge™ C18 analytical column using a binary solvent system consisting of 0.2% formic acid and 10 mm ammonium formate in ultrapure water (A) and acetonitrile (B). Good linearity was achieved over a six-point concentration range in matrix-matched calibration with determination coefficient =0.9846. Fortified pork muscle having concentrations equivalent to and double the limit of quantification (1 ng/g) yielded recovery ranges between 100.82 and 104.03% and relative standard deviations <12%. Samples (n = 5) collected from large markets located in Seoul City tested negative for PTZ residue. In conclusion, 0.2% formic acid and ammonium formate in acetonitrile can effectively extract PTZ from pork muscle without solid-phase extraction, a step normally required for cleanup before analysis and the validated method can be used for routine analysis to ensure the quality of animal products.


Subject(s)
Chromatography, Liquid/methods , Meat Products/analysis , Muscles/chemistry , Phenothiazines/analysis , Tandem Mass Spectrometry/methods , Animals , Limit of Detection , Swine
14.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1012-1013: 8-16, 2016 Feb 15.
Article in English | MEDLINE | ID: mdl-26797492

ABSTRACT

A simple analytical method based on liquid chromatography coupled with triple-quadrupole mass spectrometry was developed for detection of the veterinary drugs flumethasone, dl-methylephedrine, and 2-hydroxy-4,6-dimethylpyrimidine in porcine muscle and pasteurized cow milk. The target drugs were extracted from samples using 10mM ammonium formate in acetonitrile followed by clean-up with n-hexane and primary secondary amine sorbent (PSA). The analytes were separated on an XBridge™ hydrophilic interaction liquid chromatography (HILIC) column using 10mM ammonium formate in ultrapure water and acetonitrile. Good linearity was achieved over the tested concentrations in matrix-fortified calibrations with correlation coefficients (R(2))≥0.9686. Recovery at two spiking levels ranged between 73.62-112.70% with intra- and inter-day precisions of ≤20.33%. The limits of quantification ranged from 2-10ng/g in porcine muscle and pasteurized cow milk. A survey of market samples showed that none of them contained any of the target analytes. Liquid-liquid purification using n-hexane in combination with PSA efficiently removed the interferences during porcine and milk sample extraction. The developed method is sensitive and reliable for detection of the three target drugs in a single chromatographic run. Furthermore, it exhibits high selectivity and low quantification limits for animal-derived food products destined for human consumption.


Subject(s)
Chromatography, Liquid/methods , Ephedrine/analogs & derivatives , Flumethasone/analysis , Milk/chemistry , Muscle, Skeletal/chemistry , Pyrimidinones/analysis , Tandem Mass Spectrometry/methods , Animals , Cattle , Ephedrine/analysis , Meat/analysis , Swine
15.
J Sep Sci ; 39(5): 835-41, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26697949

ABSTRACT

A quick, easy, cheap, effective, rugged, and safe QuEChERS (method) was used for the simultaneous detection of four veterinary drug residues, namely naloxone, yohimbine, thiophanate, and altrenogest, in porcine muscle, using liquid chromatography with electrospray ionization triple quadrupole tandem mass spectrometry. Because of the unavailability of a suitable internal standard, matrix-matched calibrations were used for quantification, with determination coefficients ≥ 0.9542. The accuracy (expressed as recovery %) ranged from 60.53 to 83.25%, and the intra- and interday precisions (expressed as relative standard deviations) were <12%. The limits of quantification were 5, 0.5, 2, and 5 ng/g for naloxone, yohimbine, thiophanate, and altrenogest, respectively. Samples purchased from local markets in Seoul, Republic of Korea, revealed no traces of the target analytes. The developed method described herein is sensitive and reliable and can be applied to quantify the tested veterinary drugs in animal tissues.


Subject(s)
Drug Residues/isolation & purification , Muscles/chemistry , Naloxone/isolation & purification , Solid Phase Extraction/methods , Thiophanate/isolation & purification , Trenbolone Acetate/analogs & derivatives , Veterinary Drugs/isolation & purification , Yohimbine/isolation & purification , Animals , Chromatography, High Pressure Liquid , Drug Residues/analysis , Food Contamination/analysis , Limit of Detection , Meat/analysis , Naloxone/analysis , Swine , Tandem Mass Spectrometry , Thiophanate/analysis , Trenbolone Acetate/analysis , Trenbolone Acetate/isolation & purification , Veterinary Drugs/analysis , Yohimbine/analysis
16.
J Sep Sci ; 38(23): 4048-54, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26434939

ABSTRACT

The concentrations of residual aminopyrine and antipyrine in porcine muscle, milk, and egg samples were analyzed using liquid chromatography with tandem mass spectrometry after undergoing a series of sample pretreatment steps. Owing to an ion suppression effect, matrix-matched calibrations were used for analyte quantitation with determination coefficients (R(2) ) ≥ 0.9931. The recovery rates for aminopyrine and antipyrine in various matrices at two spiking levels (5 and 10 ng/g) fell in the range of 60.96-68.87 and 61.87-66.99%, respectively. Meanwhile, the intra- and inter-day precisions (expressed as relative standard deviation) were 1.02-12.95 and 1.71-5.50%, respectively. The method's detection limit (1 ng/g) was very low, thus enabling the detection of low residue levels. The applicability of the developed method was demonstrated with actual market samples and none of the tested analytes was detected in any of the samples.


Subject(s)
Aminopyrine/analysis , Antipyrine/analysis , Chromatography, Liquid , Eggs/analysis , Food Analysis/methods , Milk/chemistry , Muscles/chemistry , Tandem Mass Spectrometry , Aminopyrine/metabolism , Animals , Antipyrine/metabolism , Limit of Detection , Molecular Structure , Swine
17.
Mol Med Rep ; 11(1): 362-6, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25333303

ABSTRACT

The present study investigated the preventive effect of ω-3 fatty acids against cholesterol gallstone (CG) formation. CG formation was induced in C57BL/6J mice using a lithogenic diet (LD). The mice were divided into four treatment groups: i) LD, ii) LD plus eicosapentaenoic acid (EPA), iii) LD plus docosahexaenoic acid (DHA) and iv) LD plus EPA plus DHA. Subsequent to feeding the mice the LD for four weeks, EPA and/or DHA (70 mg/kg/day) were orally administered for eight weeks. The mice in the EPA treatment groups exhibited significantly less gallstone formation than those in the LD group. By contrast, DHA treatment only slightly suppressed gallstone formation. The expression of mucin 2, 5AC, 5B and 6 was significantly decreased in the gallbladders of mice in the EPA groups (70-90%) and the LD plus DHA group (30-50%), compared with that in the mice in the LD group. In addition, the mRNA expression of 3-hydroxy-3-methylglutaryl-coenzyme A reductase was significantly decreased in the livers of mice in the EPA treatment group compared with that in the livers of mice in the LD group. In conclusion, EPA was found to have a dominant anti-lithogenic effect in C57BL/6J mice.


Subject(s)
Cholesterol/metabolism , Eicosapentaenoic Acid/pharmacology , Gallstones/etiology , Gallstones/metabolism , Animals , Cholesterol/chemistry , Disease Models, Animal , Docosahexaenoic Acids/administration & dosage , Docosahexaenoic Acids/pharmacology , Eicosapentaenoic Acid/administration & dosage , Gallstones/chemistry , Gallstones/drug therapy , Gallstones/pathology , Gene Expression Regulation/drug effects , Hydroxymethylglutaryl CoA Reductases/genetics , Hydroxymethylglutaryl CoA Reductases/metabolism , Male , Mice , Mice, Inbred C57BL , Mucins/genetics , Mucins/metabolism , Receptors, LDL/genetics , Receptors, LDL/metabolism
18.
Biomed Rep ; 2(1): 89-92, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24649075

ABSTRACT

The aim of this study was to develop an analytical method for detection of imidocarb [1,3-bis[3-(4,5-dihydro-1h-imidazol-2-yl)phenyl]urea] in beef and milk using high-performance liquid chromatography (HPLC) with diode-array detection (DAD). Imidocarb was separated on a reversed-phase column (4.6×250 mm, 5 µm) with a mobile phase consisting of 85:15 (v/v) 0.1% trifluoroacetic acid/acetonitrile. The flow rate was 1 ml/min, and the column temperature was maintained at 20°C. Detection was carried out at 260 nm using a DAD detector. The analytical samples were extracted using a solid-phase extraction (SPE) method. The calibration curves showed good linearity (r≥0.998). Limits of quantifications (LOQs) were 0.15 mg/kg in beef and 0.025 mg/kg in milk. Intra- and inter-day precisions were 3.2-6.1 and 1.4-6.9%, respectively, and the accuracy (recovery) was 80.4-82.2% and 80.1-89.5% in beef and milk, respectively. Thus, an analytical protocol using SPE extraction followed by HPLC with DAD was successfully developed, which demonstrated acceptable precision and recovery.

19.
Exp Ther Med ; 5(1): 308-314, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23251289

ABSTRACT

This study was performed to produce a transcriptional database of the intestinal transporters of beagle dogs. Total RNA was isolated from the duodenum and the expression of various mRNAs was measured using GeneChip(®) oligonucleotide arrays. A total of 124 transporter genes were detected. Genes for fatty acid, peptide, amino acid and glucose and multidrug resistance/multidrug resistance-associated protein (MDR/MRP) transport were expressed at relatively higher levels than the other transporter types. The dogs exhibited abundant mRNA expression of the fatty acid transporters (fatty acid binding proteins, FABPs) FABP1 and FABP2, the ATP-binding cassettes (ABCs) ABCB1A and ABCC2, the amino acid/peptide transporters SLC3A1 and SLC15A1, the glucose transporters SLC5A1, SLC2A2 and SLC2A5, the organic anion transporter SLC22A9 and the phosphate transporters SLC20A1 and SLC37A4. In mice, a similar profile was observed with high expression of the glucose transporters SLC5A1 and SLC2As, the fatty acid transporters FABP1 and FABP2, the MDR/MRP transporters ABCB1A and ABCC2 and the phosphate transporter SLC37A4. However, the overall data reveal diverse transcriptomic profiles of the intestinal transporters of dogs and mice. Therefore, the current database may be useful for comparing the intestinal transport systems of dogs with those of mice to better evaluate xenobiotics.

20.
Int J Oncol ; 41(1): 310-6, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22552503

ABSTRACT

IL-6/6R signaling is closely associated with tumor growth and poor prognosis. Although there is evidence that interleukin-6 receptor (IL-6R)-mediated signaling promotes the growth and malignancy of cancer, the role of IL-6R in cancer stem cells (CSCs) is poorly defined. This study investigated the role of IL-6R in the proliferation of CSCs. Sphere-forming cells were isolated from the H460 non-small cell lung cancer (NSCLC) cell line and identified as CSCs using confocal microscopy, RT-PCR and WST-1 assay. The H460 spheres demonstrated the typical characteristics of CSCs, including CD133 expression, upregulation of Nanog, self-renewal, and drug resistance to methotrexate (MTX) and fluorouracil (5-FU). The release of IL-6R and its ligand, IL-6, were quantitatively determined and compared between CSCs and non-CSCs. The concentration of soluble IL-6R (sIL-6R) was remarkably high in CSCs compared to that in non-CSCs. Furthermore, significant upregulation of the IL-6R gene was also observed in the CSCs. The growth of CSCs was significantly inhibited by transfection with IL-6R small-interfering RNA (siRNA), as well as with the IL-6R monoclonal antibody (mAb). In addition, blocking both IL-6R and IL-6 using siRNA or mAbs intensified the inhibition of CSC proliferation. These findings indicate that IL-6R is present in CSCs and has an important role in the proliferation of CSCs in the H460 lung cancer cell line. Therefore, we suggest that IL-6R is both a viable target for the development of CSC-directed lung cancer therapeutics and a potential CSC marker in NSCLC.


Subject(s)
Cell Proliferation , Interleukin-6/physiology , Neoplastic Stem Cells/physiology , Receptors, Interleukin-6/metabolism , Antibodies, Neutralizing/pharmacology , Antimetabolites, Antineoplastic/pharmacology , Carcinoma, Non-Small-Cell Lung , Cell Line, Tumor , Fluorouracil/pharmacology , Gene Expression , Gene Knockdown Techniques , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Interleukin-6/genetics , Interleukin-6/metabolism , Lung Neoplasms , Methotrexate/pharmacology , Nanog Homeobox Protein , Neoplastic Stem Cells/metabolism , RNA Interference , Receptors, Interleukin-6/antagonists & inhibitors , Receptors, Interleukin-6/genetics , Signal Transduction/drug effects , Spheroids, Cellular/metabolism , Spheroids, Cellular/physiology , Up-Regulation
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