Lipid Profiles Obtained from MALDI Mass Spectrometric Imaging in Liver Cancer Metastasis Model.

Liver cancer metastasis is known to be a poor prognosis and a leading cause of mortality. To overcome low therapeutic efficacy, understanding the physiological properties of liver cancer metastasis is required. However, the metastatic lesion is heterogeneous and complex. We investigate the distribution of lipids using matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) in an experimental metastasis model. We obtained the differentially expressed mass peaks in comparison between normal sites and metastatic lesions. The relationship of mass to charge ratio (m/z) and intensity were measured, m/z-indicated species were analyzed by MALDI-MS/MS analysis, and identification of these mass species was confirmed using the METASPACEannotation platform and Lipid Maps®. MALDI-MSI at m/z 725.6, 734.6, 735.6, 741.6, 742.6, 744.6, 756.6, and 772.6 showed significantly higher intensity, consistent with the metastatic lesions in hematoxylin-stained tissues. Sphingomyelin SM [d18:0/16:1], phosphatidylcholine (PC) [32:0], PC [31:0], PC [31:1], and PE [36:2] were highly expressed in metastatic lesions. Our results could provide information for understanding metastatic lesions. It suggests that the found lipids could be a biomarker for the diagnosis of metastatic lesions.

Adverse drug events leading to emergency department visits: A multicenter observational study in Korea.

Adverse drug events are significant causes of emergency department visits. Systematic evaluation of adverse drug events leading to emergency department visits by age is lacking. This multicenter retrospective observational study evaluated the prevalence and features of adverse drug event-related emergency department visits across ages. We reviewed emergency department medical records obtained from three university hospitals between July 2014 and December 2014. The proportion of adverse drug events among total emergency department visits was calculated. The cause, severity, preventability, and causative drug(s) of each adverse drug event were analyzed and compared between age groups (children/adolescents [<18 years], adults [18-64 years], and the elderly [≥65 years]). Of 59,428 emergency department visits, 2,104 (3.5%) were adverse drug event-related. Adverse drug event-related emergency department visits were more likely to be female and older. Multivariate logistic regression analysis revealed that compared to non- adverse drug event-related cases, adverse drug event-related emergency department visitors were more likely to be female (60.6% vs. 53.6%, p<0.001, OR 1.285, 95% CI 1.025-1.603) and older (50.8 ± 24.6 years vs. 37.7 ± 24.4 years, p<0.001, OR 1.892, 95% CI: 1.397-2.297). Comorbidities such as diabetes, chronic kidney disease, chronic liver disease, and malignancies were also significantly associated with adverse drug event-related emergency department visits. Side effects were the most common type of adverse drug events across age groups, although main types differed substantially depending on age. Serious adverse drug events, hospitalizations, and adverse drug event-related deaths occurred more frequently in the elderly than in adults or children/adolescents. The proportion of adverse drug event-related emergency department visits that were preventable was 15.3%. Causative drugs of adverse drug events varied considerably depending on age group. Adverse drug event features differ substantially according to age group. The findings suggest that an age-specific approach should be adopted in the preventive strategies to reduce adverse drug events.

[Imaging Findings of a Malignant Rhabdoid Tumor in the Stomach: A Case Report]. / 위에 발생한 ì• ì„± 횡문근양 ì¢ ì–‘ì˜ 영상 소견: 증례 ë³´ê³ .

A malignant rhabdoid tumor is an aggressive tumor that occurs mainly in the kidney of infants and children. When it occurs in extrarenal sites, it is referred to as an extrarenal malignant rhabdoid tumor. Although a few cases of malignant rhabdoid tumor occuring in the central nervous system, liver, brain, skin, and soft tissue have been reported, it is rarely observed in the stomach. We report the imaging findings of a malignant rhabdoid tumor of the stomach that mimicked a gastric lymphoma in a patient who presented with melena.

[Imaging Findings of Primary Adrenal Leiomyosarcoma: A Case Report]. / ë¶€ì‹ ì˜ 원발성 í‰í™œê·¼ìœ¡ì¢ ì˜ 영상 소견: 증례 ë³´ê³ .

Leiomyosarcoma is a malignant tumor that typically originates from either the uterus or the retroperitoneum. Furthermore, primary adrenal leiomyosarcoma is an extremely rare condition. Owing to its radiological non-specificity, differentiating leiomyosarcoma from other tumor types in the adrenal gland is difficult. We report the imaging findings of a primary adrenal leiomyosarcoma in a patient who presented with left upper quadrant abdominal pain, which increased by more than 1 cm in diameter in two years. Primary adrenal leiomyosarcoma was diagnosed considering the subsequent surgical and histopathologic findings.

A Simple, Rapid and Reliable Method to Determine Imipramine and Desipramine in Mouse Serum Using Ultra-High-Performance Liquid Chromatography-Quadrupole-Time-of-Flight Mass Spectrometry.

A rapid and sensitive ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometric (UHPLC-Q-TOF-MS) method was developed for quantification of imipramine, one of the most widely used tricyclic antidepressants, and desipramine, an active metabolite of imipramine, in mouse serum. The developed method included a simple protein precipitation with acetonitrile in 50 µL of serum and analyte separation on an Acquity UPLC BEH C18 column using a gradient elution of acetonitrile with 0.1% formic acid and 20 mM ammonium formate. As a result, the entire analysis time was <20 min including the sample preparation and the LC-MS analysis. The limit of quantification was 5.0 ng mL(-1) for both imipramine and desipramine, and calibration curves were linear over the concentration range of 5.0-1,000.0 and 5.0-250.0 ng mL(-1) for imipramine and desipramine, respectively. Intraday precisions at three levels were 2.2-3.6 and 1.7-4.2% for imipramine and desipramine, respectively, whereas interday precisions were 2.6-5.0 and 2.0-8.4% for imipramine and desipramine, respectively. Accuracy ranged between 93.6 and 106.6% for imipramine and 94.1 and 106.4% for desipramine. Absolute recovery was 96.0-97.6% for imipramine and 87.0-99.5% for desipramine. Finally, the described method was applied to mice administered with imipramine, demonstrating the suitability for quantification of imipramine and desipramine for therapeutic drug monitoring or bioequivalence studies.

Screening newborns for metabolic disorders based on targeted metabolomics using tandem mass spectrometry.

The main purpose of newborn screening is to diagnose genetic, metabolic, and other inherited disorders, at their earliest to start treatment before the clinical manifestations become evident. Understanding and tracing the biochemical data obtained from tandem mass spectrometry is vital for early diagnosis of metabolic diseases associated with such disorders. Accordingly, it is important to focus on the entire diagnostic process, including differential and confirmatory diagnostic options, and the major factors that influence the results of biochemical analysis. Compared to regular biochemical testing, this is a complex process carried out by a medical physician specialist. It is comprised of an integrated program requiring multidisciplinary approach such as, pediatric specialist, expert scientist, clinical laboratory technician, and nutritionist. Tandem mass spectrometry is a powerful tool to improve screening of newborns for diverse metabolic diseases. It is likely to be used to analyze other treatable disorders or significantly improve existing newborn tests to allow broad scale and precise testing. This new era of various screening programs, new treatments, and the availability of detection technology will prove to be beneficial for the future generations.

Caffeic acid: potential applications in nanotechnology as a green reducing agent for sustainable synthesis of gold nanoparticles.

The sustainable synthesis of gold nanoparticles from gold ions was conducted with caffeic acid as a green reducing agent. The formation of gold nanoparticles was confirmed by spectroscopic and microscopic methods. Spherical nanoparticles with an average diameter of 29.99 ± 7.43 nm were observed in high- resolution transmission electron microscopy and atomic force microscopy images. The newly prepared gold nanoparticles exhibited catalytic activity toward the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride. This system enables the preparation of green catalysts using plant natural products as reducing agents, which fulfills the growing need for sustainability initiatives.

Erratum to: Screening newborns for metabolic disorders based on targeted metabolomics using tandem mass spectrometry.

[This corrects the article on p. 119 in vol. 20, PMID: 26512346.].

Quantification of 4-methylimidazole in carbonated beverages by ultra-performance liquid chromatography-tandem mass spectrometry.

2- and 4-methylimidazoles (2-MI and 4-MI) are undesired byproducts produced during the manufacture of caramel color used to darken food products such as carbonated beverages. The Office of Environmental Health Hazard Assessment in California listed 4-MI as carcinogen in January 2011 with a proposed no significant risk level at 29 µg per person per day. Thus, a quantitative analytical measurement for 2-MI and 4-MI is desired for reliable risk assessments for exposure. An ultra-performance liquid chromatography (UPLC) coupled tandem mass spectrometric (MS/MS) method was developed for the quantification of 4-MI in beverage samples. Chromatographic separation of 2-MI and 4-MI were achieved by using a PFP reversed-phase column and a stepwise gradient of methanol and distilled water containing 0.1 % formic acid. Identification and quantification of 2-MI and 4-MI were performed using electrospray ionization-tandem mass monitoring the precursor to product ion transitions for 2-MI at m/z 83.1 → 42.2 and 4-MI at m/z 83.1 → 56.1 with melamine at m/z 127.1 → 85.1 as the internal standard. The performance of the method was evaluated against validation parameters such as specificity, carryover, linearity and calibration, correlation of determination (r(2)), detection limit, precision, accuracy, and recovery. Calibration curves at 10-400 ng/mL were constructed by plotting concentration versus peak-area ratio (analyte/internal standard) and fitting the data with a weighted 1/x. The accuracy of the assay ranged from 93.58 to 110.53 % for all analytes. Intra-assay precision for 2-MI and 4-MI were below 7.28 (relative standard deviation/RSD %) at QC samples. Here we present a new and improved method using UPLC-MS/MS to significantly simplify sample preparation and decrease chromatographic run time. This method allows accurate and reproducible quantification of 4-MI in carbonated beverages as low as sub ng/mL (ppb) levels.

Determination of plasma dibasic amino acids following trimethylsilyl-trifluoroacyl derivatization using gas chromatography-mass spectrometry.

A rapid analytical method was developed to quantify dibasic amino acids (ornithine, lysine and arginine) after two-step derivatization procedure with good sensitivity and specificity on human plasma. If early diagnosis has not been made, patients with inborn metabolic disorders such as HHH syndrome, Hyperornithinemia and dibasic aminoaciduria rapidly progress to sudden death, physical defect or mental retardation resulting in storage of the toxic material into the brain. Therefore, it is necessary to develop the analytical method for rapid screening and/or correct confirmation diagnosis. The formation of trimethylsilyl derivative of the carboxylic (COO-) functional group was performed by adding MSTFA. Five µL of methyl orange was added to the residue until the color changed into yellow. Consecutively, the trifluoroacyl derivative of the amino (-NH2) functional group was produced by adding MBTFA. Specific ions was chosen for quantification with following ions; m/z 166 and m/z 212 for ornithine, m/z 180 and m/z 395 for lysine, and m/z 292 and, m/z 519 for arginine. A calibration curve showed a linear relationship for the dibasic amino acids spiked to pooled normal plasma showing R(2) of 0.9955-0.9979 in the range of 0.1-600 ng investigated. The utility of the method for screening and diagnosis was demonstrated by recovery 80-125 % and reproducibility with RSD (9-17 %) at low, medium and high concentration fortified to pooled plasma. Collectively, the present study suggest that this method could be useful for diagnosis, screening, therapeutic monitoring of metabolic disorders on dietary therapy with excellent sensitivity and rapidity.

Methionine/galactose ratio on newborn blood spots useful for reduction of false positives for homocystinuria and galactosemia by high-performance anion-exchange chromatography with pulsed amperometric detection.

BACKGROUND: Methionine (Met) in blood and urine is a useful diagnostic marker for homocystinuria (HCU). However, galactosemia could be misdiagnosed as HCU when Met is used as the sole marker, since elevated excretion of Met presents in both galactosemia and HCU. Use of a more specific diagnostic marker in addition to Met is therefore necessary for reduction of false positive results for HCU as well as confirmative diagnosis of HCU. METHODS: Chromatographic separation was performed using an anion-exchange column. The levels of Met and galactose (Gal) on blood were measured and Met/Gal ratios were calculated from blood spot samples from 300 normal volunteers, eight galactosemia patients, and three HCU patients. RESULTS: The Met/Gal ratio ranged 0-4.95 for normal blood spots (n=300), 0-0.22 for galactosemia samples (n=8), and >1250 for HCU patient samples. CONCLUSIONS: Separation, extraction, and deproteinization procedures were established for Met and Gal in blood spots. And Met/Gal ratio allowed HCU to clearly distinguish from galactosemia. As a way of second tier confirmative analysis, the ratio is the best way to reduce false positives. The assay is most appropriate to reduce false positives in labs that do not screen for galactosemia.

Chromatographic diagnosis of maple syrup urine disease by measuring the L-alloisoleucine/L-phenylalanine ratio in dried blood spots.

A high-performance ligand-exchange chromatography with ultraviolet detection method for confirmation diagnosis of maple syrup urine disease (MSUD) was developed that relies on the determination of branched-chain amino acids (BCAAs) and Phe levels in blood. The dynamic ranges for the BCAAs and Phe were 50-1000 µM (r(2)=0.9982-0.9996) and 74-873 µM (r(2)=0.9992) from a dried blood spot, and the BCAA detection limits (S/N=3) were 0.43-1.91 µM. The mean recoveries of BCAA for intra- and inter-day assays were 92.1-103.0%. The ranges of alloisoleucine (Allo-Ile)/Phe ratio were ND-0.04 and 1.5-2.4 for PKU and MSUD patient samples, respectively. The lowest ratio (1.5) of the MSUD samples was 37.5 times higher than the highest ratio (0.04) of the PKU samples. Therefore, the Allo-Ile/Phe ratio was very useful biomarker for confirmation diagnosis of MSUD.

Serum globotriaosylceramide assay as a screening test for fabry disease in patients with ESRD on maintenance dialysis in Korea.

BACKGROUND/AIMS: Fabry disease is an X-linked recessive and progressive disease caused by α-galactosidase A (α-GaL A) deficiency. We sought to assess the prevalence of unrecognized Fabry disease in dialysis-dependent patients and the efficacy of serum globotriaosylceramide (GL3) screening. METHODS: A total of 480 patients of 1,230 patients among 17 clinics were enrolled. Serum GL3 levels were measured by tandem mass spectrometry. Additionally, we studied the association between increased GL3 levels and cardiovascular disease, cerebrovascular disease, or left ventricular hypertrophy. RESULTS: Twenty-nine patients had elevated serum GL3 levels. The α-GaL A activity was determined for the 26 patients with high GL3 levels. The mean α-GaL A activity was 64.6 nmol/hr/mg (reference range, 45 to 85), and no patient was identified with decreased α-GaL A activity. Among the group with high GL3 levels, 15 women had a α-GaL A genetics analysis. No point mutations were discovered among the women with high GL3 levels. No correlation was observed between serum GL3 levels and α-GaL A activity; the Pearson correlation coefficient was 0.01352 (p = 0.9478). No significant correlation was observed between increased GL3 levels and the frequency of cardiovascular disease or cerebrovascular disease. CONCLUSIONS: Fabry disease is very rare disease in patients with end-stage renal disease. Serum GL3 measurements as a screening method for Fabry disease showed a high false-positive rate. Thus, serum GL3 levels determined by tandem mass spectrometry may not be useful as a screening method for Fabry disease in patients with end stage renal disease.

Simultaneous diagnostic method for phenylketonuria and galactosemia from dried blood spots using high-performance liquid chromatography-pulsed amperometric detection.

We developed a simultaneous diagnostic method for phenylketonuria (PKU) and galactosemia through simultaneous determination of phenylalanine (Phe) and galactose (Gal) by high-performance liquid chromatography (HPLC) with pulsed amperometric detection (PAD). The intra- and inter-day precisions were <5.8%, with satisfactory mean recoveries (98.2-105%). For all PKU-positive samples, Phe levels were above the cut-off value (>30.0 mg/L), but Gal levels were nearly zero. For 77% of galactosemia-positive samples, Phe levels were above the cut-off value, but Gal levels were above the cut-off value (>80.0 mg/L) for all samples. Our HPLC-PAD method can reduce the false-positive rate of misdiagnosis for PKU and galactosemia.

Determination of pipecolic acid following trimethylsilyl and trifluoroacyl derivatisation on plasma filter paper by stable isotope GC-MS for peroxisomal disorders.

If early diagnosis is not made, patients with peroxisomal disorders rapidly progress to sudden death, physical defect or mental retardation resulted in storage of the toxic material into the brain. Therefore, it is necessary to develop the analytical method for rapid screening and/or correct confirmation diagnosis. The method utilizes [2H(9)]pipecolic acid as internal standard. The formation of trimethylsilyl derivative (TMS) of the carboxylic functional group was performed by adding MSTFA. And then 5 microL of methyl orange was added until the color of methyl orange was to yellow. Consecutively, the trifluoroacyl (TFA)-derivative of the -NH functional group was produced by adding MBTFA. GC-MS was set with specific ions (m/z 282, m/z 297) of the TMSTFA derivative of pipecolic acid for selected ion monitoring. The linearity of pipecolic acid in pooled plasma spots showed 0.9999 in the range of 10-150 ng investigated. The precision and accuracy was within S.D. of 5% (RSD, within 5%) for intra-day and inter-day assay. Normal control value has been determined in plasma spots of infant and adults aged 0-30 (including newborn). The utility of the method was demonstrated by quantifying various concentration of fortified pipecolic acid on a filter plasma spot. The new method was simple with just two step derivatisation, time and labor saving without SPE or liquid-liquid extraction, and convenience of delivery owing to the use of filter paper. The described method could be used for routine analysis, monitoring, and clinical diagnostic application of peroxisomal disorders on dietary therapy.

Determination of phenylalanine in blood by high-performance anion-exchange chromatography-pulsed amperometric detection to diagnose phenylketonuria.

We have developed a high-performance anion-exchange chromatography with pulsed amperometric detection method for the detection of phenylalanine (Phe) and diagnosis of phenylketonuria (PKU). Sample pretreatment steps were simplified without derivatization. The analyte was separated within 5 min. The detection limit (S/N=3) for Phe was 50 pg. Linear dynamic range was 1.23-14.43 mg/dL (r(2)=0.9999) for a dried blood spot. The mean recoveries of Phe for intra- and inter-day assays were found to be 96.87-104.16%. This method clearly differentiated PKU-positive groups from normal groups, and proved to be a practical procedure for rapid screening and follow-up monitoring of PKU.

Short-term efficacy of enzyme replacement therapy in Korean patients with Fabry disease.

Fabrazyme has been widely used for treatment of Fabry disease since its approval by the U.S. Food and Drug Administration in 2003. This study was undertaken to assess the short-term efficacy and safety of enzyme replacement therapy (ERT) for Fabry disease in Korea. Eight male patients and three female symptomatic carriers aged 13 to 48 yr were included. Fabrazyme was administered by intravenous infusion at a dose of 1 mg/kg every 2 weeks. Plasma and urine globotriaosylceramide (GL-3) levels, serum creatinine, creatinine clearance, and 24-hr urine protein levels were measured every 3 months. Kidney biopsies, ophthalmologic exams, and pure tone audiometry were performed before and 1 yr after ERT. Kidney function, including serum creatinine, creatinine clearance, and the 24-hr urine protein level, remained stable during ERT. Plasma and urine GL-3 levels were reduced within 3 to 6 months of ERT initiation. Microvascular endothelial deposits of GL-3 were decreased from renal biopsy specimens after 1 yr of treatment. The severity of sensorineural hearing loss and tinnitus did not improve after ERT. ERT is safe and effective in stabilizing renal function and clearing microvascular endothelial GL-3 from kidney biopsy specimen in Korean patients with Fabry disease.

A pulsed amperometric detection method of galactose 1-phosphate for galactosemia diagnosis.

Galactose 1-phosphate uridyltransferase deficiency causes the accumulation of galactose and galactose 1-phosphate (Gal 1-P) in the blood. We describe a new pulsed amperometric detection method for determining Gal 1-P levels as a pathognomic marker for the diagnosis of galactosemia. The method uses high-performance anion-exchange chromatography with pulsed amperometric detection. In an anion-exchange column, the analytes were separated in 5 min by the eluent mixture of 40 mM NaOH and 40 mM Na(2)CO(3). The detection limit (signal to noise ratio of 3) to Gal 1-P was 30 microg/dL. The linear dynamic range was 3.0-50 mg/dL (r(2)=0.9999). The mean recoveries of Gal 1-P for intra- and interday assays were 97.55-103.78%. This method clearly separated the type I galactosemia patients from the normal group and is a practical procedure for the rapid diagnosis of galactosemia.

PHEX gene mutations and genotype-phenotype analysis of Korean patients with hypophosphatemic rickets.

X-linked hypophosphatemic rickets (XLH) results from mutations in the PHEX gene. Mutational analysis of the PHEX gene in 15 unrelated Korean patients with hypophosphatemic rickets revealed eight mutations, including five novel mutations, in nine patients: two nonsense mutations, two missense mutations, one insertion, and three splicing acceptor/donor site mutations. Of these, c.64G>T, c.1699C>T, c.466_467 insAC, c.1174-1G>A, and c.1768+5G>A were novel mutations. To analyze the correlation between genotype and phenotype, phenotypes were compared between groups with and without a mutation, in terms of mutation location, mutation type, and sex. Skeletal disease tended to be more severe in the group with a mutation in the C-terminal half of the PHEX gene, but no genotype-phenotype correlation was detected in other comparisons. Further extensive studies of the PHEX gene mutations and analyses of the genotype-phenotype relationships are required to understand PHEX function and the pathogenesis of XLH.