Pooled Urine Samples Research Articles

Quantitative determination of hydroxy polycylic aromatic hydrocarbons as a biomarker of exposure to carcinogenic polycyclic aromatic hydrocarbons

A high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) method was developed for quantitative analysis of hydroxy polycyclic aromatic hydrocarbons (OH-PAHs). Four hydroxy metabolites of known and suspected carcinogenic PAHs (benzo[a]pyrene (B[a]P), benz[a]anthracene (B[a]A), and chrysene (CRY)) were selected as suitable biomarkers of PAH exposure and associated risks to human health. The analytical method included enzymatic deconjugation, liquid − liquid extraction, followed by derivatization with methyl-N-(trimethylsilyl) trifluoroacetamide and instrumental analysis. Photo-induced oxidation of target analytes − which has plagued previously published methods − was controlled by a combination of minimizing exposure to light, employing an antioxidant (2-mercaptoethanol) and utilizing a nitrogen atmosphere. Stability investigations also indicated that conjugated forms of the analytes are more stable than the non-conjugated forms. Accuracy and precision of the method were 77.4–101% (<4.9% RSD) in synthetic urine and 92.3–117% (<15% RSD) in human urine, respectively. Method detection limits, determined using eight replicates of low-level spiked human urine, ranged from 13 to 24pg/mL. The method was successfully applied for analysis of a pooled human urine sample and 78 mouse urine samples collected from mice fed with PAH-contaminated diets. In mouse urine, greater than 94% of each analyte was present in its conjugated form.

Toward Levofloxacin Monitoring in Human Urine Samples by Employing the LoC-SERS Technique

The pharmacokinetics of antibiotics such as levofloxacin exhibits large interindividual differences, questioning the value of fixed dose regimens and warranting individual dosing based on therapeutic drug monitoring. Here, in a proof of principal study, it is shown that levofloxacin can be detected in human urine samples by employing lab-on-a-chip surface enhanced Raman spectroscopy (LoC-SERS). First, artificial urine is used as a matrix in order to get insights into the influence of different parameters such as matrix complexity, aggregation time, and matrix dilution on the overall SERS signal. Second, three anonymized individual and three pooled urine samples originating from patients undergoing either no or unknown medical treatments have been spiked with the target analyte. Measurements were performed with a benchtop and a portable Raman setup. In all six samples urinary levofloxacin concentrations between 0.45 mM (162.6 μg/mL) and 1.8 mM (650.5 μg/mL) have been successfully detected. According to the...

A method for comparative metabolomics in urine using high resolution mass spectrometry

Developing a workflow for metabolite profiling from biological fluids using mass spectrometry is imperative to extract accurate information. In this study, urine samples from smokers (n=10) and nonsmokers (n=10) were analyzed using an ultrahigh performance liquid chromatography–high resolution mass spectrometry (UHPLC–HRMS) system. For the analysis, two different chromatographic methods [Reversed phase chromatography (RPC) and Hydrophilic interaction liquid chromatography (HILIC)], in two ionization modes (positive and negative) were used. Spiked reserpine (positive ion mode) or taurocholate (negative ion mode) were used for data extraction and normalization. Quality controls (QCs), prepared by pooling urine samples from both smokers and non-smokers (each n=10), were used to assess the reproducibility of the method. The final data output from SIEVE 2.2 after applying a cut-off for QC coefficient of variation (CV) <20% and p-value <0.05 showed 165, 83, 177 and 100 unique components in RP positive/negative, HILIC positive/negative modes, respectively. Statistical analysis showed clustering of the two groups and the QCs, while the variable importance in projection (VIP) scores for the top fifteen metabolites in each of the four modes indicated the metabolites most responsible for the differences. Application of the developed workflow for comparative metabolomic analysis of urine in different diseased models will be of great use in the field of clinical metabolomics.

Development and validation of a CE-MS method for the targeted assessment of amino acids in urine.

A CE-ESI-MS method was developed and validated for the separation and quantitative analysis of amino acids (AA) in urine. Experimental parameters related to the CE-MS interface, BGE, and mass spectrometer (MS) settings were optimized providing a good separation of 27 AA, including the isomers L-leucine, L-isoleucine, and L-alloisoleucine, in less than 30 min. The sheath liquid was composed by 0.50% formic acid in 60% (v,v) methanol-water delivered at a flow rate of 5 μL/min. The BGE consisted of 0.80 mol/L formic acid at pH 1.96 and 15% methanol. A pH stacking procedure was implemented to enhance sensitivity (a 12.5% NH4 OH solution was injected at 0.5 psi/9 s prior to samples injected at 0.6 psi/20 s). The proposed method was validated according to FDA and ICH protocols exhibiting acceptable parameters. Analytical curves presented coefficients of determination from 0.996 to 0.9997 (with large F statistics and low p-values). LODs and quantification ranged from 0.63 to 29 μmol/L and from 1.9 to 86 μmol/L, respectively. Practical repeatability was obtained for all AA with coefficients of variation better than 0.55% CV (migration time) and 1.7% CV (peak area ratios; methionine sulfone as internal standard). Recoveries of AA in spiked urine ranged from 92.0 to 123% with few exceptions. Moreover, a successful quantification of AA in pooled control and test urine samples, which compose a vesicoureteral reflux cohort, was achieved showing the potential applicability of the proposed method for targeted metabolomics studies using CE-ESI-MS with an Ion Trap as mass analyzer.

Urinary deoxynivalenol (DON) and zearalenone (ZEA) as biomarkers of DON and ZEA exposure of pigs.

Four diets contaminated with 1.1 to 5.0 mg/kg deoxynivalenol (DON) and 0.4 to 2.4 mg/kg zearalenone (ZEA) were fed to four groups of six growing Large White pigs. Urine samples were collected after 3 to 4 days and again after 6 to 7 days on the diets. On each sampling day, half of the animals were sampled in the morning, after an 8-h fast, and the other half were sampled in the afternoon, after 7 h of ad libitum access to feed. The urinary concentrations of DON, DON-glucuronide, DON-3-sulphate, de-epoxy-DON, as well as of ZEA, ZEA-14-glucuronide, α-zearalenol and α-zearalenol-14-glucuronide, analysed using LC-MS/MS, were used to calculate urinary DON and ZEA equivalent concentrations (DONe and ZEAe). The urinary concentration of DONe (P < 0.001), but not of ZEAe (P = 0.31), was lower in the fasted than that in the fed animals. The urinary DONe/creatinine and ZEAe/creatinine ratios were highly correlated with DON and ZEA intake per kg body weight the day preceding sampling (r = 0.76 and 0.77; P < 0.001). The correlations between DON intake during the 7 h preceding urine sampling in the afternoon and urinary DONe/creatinine ratio (r = 0.88) as well as between mean ZEA intake during 3 days preceding urine sampling and urinary ZEAe/creatinine ratio (r = 0.84) were even higher, reflecting the plasma elimination half-time of several hours for DON and of more than 3 days for ZEA. ZEAe analysed in enzymatically hydrolysed urine using an ELISA kit was highly correlated with the LC-MS/MS data (r = 0.94). The urinary DONe and ZEAe to creatinine ratios, analysed in pooled urine samples of several pigs fed the same diet, can be used to estimate their exposure to DON and ZEA.

Determination of glucuronide conjugates of hydroxyl triphenyl phosphate (OH-TPHP) metabolites in human urine and its use as a biomarker of TPHP exposure

In vitro studies using avian hepatocytes or human liver microsomes suggest that hydroxylation is an important pathway in the metabolism of triphenyl phosphate (TPHP), a chemical used as a flame retardant and plasticizer. TPHP metabolism can lead to the formation of para(p)- and meta(m)-hydroxyl-(OH-)TPHP products as well as their glucuronide conjugates. To determine whether the TPHP hydroxylation and depuration pathway also occurs in vivo in humans, the present study developed a sensitive method for quantification of p- and m-OH-TPHP glucuronides in human urine samples. In n = 1 pooled urine sample and n = 12 individual urine samples collected from four human volunteers from Ottawa (ON, Canada), p- and m-OH-TPHP glucuronides were detectable in 13 and 9 of the 13 analyzed samples and at concentrations ranging from <MLOQ-25 pg/mL and nd-4 pg/mL, respectively. A strong, positive correlation (p = 0.02, r = 0.6569) was observed between p-OH-TPHP glucuronide and diphenyl phosphate concentrations (DPHP, a known dealkylated metabolite of TPHP). To our knowledge, this is the first report demonstrating that TPHP hydroxylation and conjugation occurs in vivo in humans, and further suggests that p-OH-TPHP glucuronide can be used as a specific biomarker of TPHP exposure in humans.

Target and suspect screening of psychoactive substances in sewage-based samples by UHPLC-QTOF

The quantification of illicit drug and pharmaceutical residues in sewage has been shown to be a valuable tool that complements existing approaches in monitoring the patterns and trends of drug use. The present work delineates the development of a novel analytical tool and dynamic workflow for the analysis of a wide range of substances in sewage-based samples. The validated method can simultaneously quantify 51 target psychoactive substances and pharmaceuticals in sewage-based samples using an off-line automated solid phase extraction (SPE-DEX) method, using Oasis HLB disks, followed by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-QTOF) in MSe. Quantification and matrix effect corrections were overcome with the use of 25 isotopic labeled internal standards (ILIS). Recoveries were generally greater than 60% and the limits of quantification were in the low nanogram-per-liter range (0.4–187 ng L−1). The emergence of new psychoactive substances (NPS) on the drug scene poses a specific analytical challenge since their market is highly dynamic with new compounds continuously entering the market. Suspect screening using high-resolution mass spectrometry (HRMS) simultaneously allowed the unequivocal identification of NPS based on a mass accuracy criteria of 5 ppm (of the molecular ion and at least two fragments) and retention time (2.5% tolerance) using the UNIFI screening platform. Applying MSe data against a suspect screening database of over 1000 drugs and metabolites, this method becomes a broad and reliable tool to detect and confirm NPS occurrence. This was demonstrated through the HRMS analysis of three different sewage-based sample types; influent wastewater, passive sampler extracts and pooled urine samples resulting in the concurrent quantification of known psychoactive substances and the identification of NPS and pharmaceuticals.

Biological Monitoring of Human Exposure to Neonicotinoids Using Urine Samples, and Neonicotinoid Excretion Kinetics.

BackgroundNeonicotinoids, which are novel pesticides, have entered into usage around the world because they are selectively toxic to arthropods and relatively non-toxic to vertebrates. It has been suggested that several neonicotinoids cause neurodevelopmental toxicity in mammals. The aim was to establish the relationship between oral intake and urinary excretion of neonicotinoids by humans to facilitate biological monitoring, and to estimate dietary neonicotinoid intakes by Japanese adults.Methodology/Principal FindingsDeuterium-labeled neonicotinoid (acetamiprid, clothianidin, dinotefuran, and imidacloprid) microdoses were orally ingested by nine healthy adults, and 24 h pooled urine samples were collected for 4 consecutive days after dosing. The excretion kinetics were modeled using one- and two-compartment models, then validated in a non-deuterium-labeled neonicotinoid microdose study involving 12 healthy adults. Increased urinary concentrations of labeled neonicotinoids were observed after dosing. Clothianidin was recovered unchanged within 3 days, and most dinotefuran was recovered unchanged within 1 day. Around 10% of the imidacloprid dose was excreted unchanged. Most of the acetamiprid was metabolized to desmethyl-acetamiprid. Spot urine samples from 373 Japanese adults were analyzed for neonicotinoids, and daily intakes were estimated. The estimated average daily intake of these neonicotinoids was 0.53–3.66 μg/day. The highest intake of any of the neonicotinoids in the study population was 64.5 μg/day for dinotefuran, and this was <1% of the acceptable daily intake.

Monitoring exposure to polycyclic aromatic hydrocarbons in an Australian population using pooled urine samples

Integrated exposure to polycyclic aromatic hydrocarbons (PAHs) can be assessed through monitoring of urinary mono-hydroxylated PAHs (OH-PAHs). The aim of this study was to provide the first assessment of exposure to PAHs in a large sample of the population in Queensland, Australia including exposure to infant (0–4years). De-identified urine specimens, obtained from a pathology laboratory, were stratified by age and sex, and pooled (n=24 pools of 100) and OH-PAHs were measured by gas chromatography–isotope dilution–tandem mass spectrometry. Geometric mean (GM) concentrations ranged from 30ng/L (4-hydroxyphenanthrene) to 9221ng/L (1-naphthol). GM of 1-hydroxypyrene, the most commonly used PAH exposure biomarker, was 142ng/L. The concentrations of OH-PAHs found in this study are consistent with those in developed countries and lower than those in developing countries. We observed no association between sex and OH-PAH concentrations. However, we observed lower urinary concentrations of all OH-PAHs in samples from infants (0–4years), children (5–14years) and the elderly (>60year old) compared with samples from other age groups (15–29, 30–44 and 45–59years) which may be attributed to age-dependent behaviour-specific exposure sources.

Spatiotemporal Aspects of Hendra Virus Infection in Pteropid Bats (Flying-Foxes) in Eastern Australia.

Hendra virus (HeV) causes highly lethal disease in horses and humans in the eastern Australian states of Queensland (QLD) and New South Wales (NSW), with multiple equine cases now reported on an annual basis. Infection and excretion dynamics in pteropid bats (flying-foxes), the recognised natural reservoir, are incompletely understood. We sought to identify key spatial and temporal factors associated with excretion in flying-foxes over a 2300 km latitudinal gradient from northern QLD to southern NSW which encompassed all known equine case locations. The aim was to strengthen knowledge of Hendra virus ecology in flying-foxes to improve spillover risk prediction and exposure risk mitigation strategies, and thus better protect horses and humans. Monthly pooled urine samples were collected from under roosting flying-foxes over a three-year period and screened for HeV RNA by quantitative RT-PCR. A generalised linear model was employed to investigate spatiotemporal associations with HeV detection in 13,968 samples from 27 roosts. There was a non-linear relationship between mean HeV excretion prevalence and five latitudinal regions, with excretion moderate in northern and central QLD, highest in southern QLD/northern NSW, moderate in central NSW, and negligible in southern NSW. Highest HeV positivity occurred where black or spectacled flying-foxes were present; nil or very low positivity rates occurred in exclusive grey-headed flying-fox roosts. Similarly, little red flying-foxes are evidently not a significant source of virus, as their periodic extreme increase in numbers at some roosts was not associated with any concurrent increase in HeV detection. There was a consistent, strong winter seasonality to excretion in the southern QLD/northern NSW and central NSW regions. This new information allows risk management strategies to be refined and targeted, mindful of the potential for spatial risk profiles to shift over time with changes in flying-fox species distribution.

P07.05 Utility of pooled urine samples for detection ofchlamydia trachomatisinfection in asymptomatic pregnant women in northern india

Background Urogenital infections by Chlamydia trachomatis (CT) are the most prevalent sexually-transmitted bacterial diseases in women. Cost effective screening of women for C. trachomatis infection in developing countries is highly desirable for reducing morbidity and complications like pelvic inflammatory diseases, ectopic pregnancy and infertility. Results of noninvasive urine samples tests for C. trachomatis are nearly identical to samples collected directly from the cervix or urethra. The present study used the pooled urine samples to decrease the cost of screening for C. trachomatis . Methods First void urine samples were collected from 1000 asymptomatic pregnant women having gestational age less than 24 weeks attending the Antenatal Clinics at PGIMER, Chandigarh during July 2009 to June 2012. The pooled urine samples (5x pooled processed specimen) were tested for presence of C. trachomatis by Amplicor CT PCR kit (Roche Diagnostic) and positive results were further tested separately on each urine sample. Direct fluroscent antibody test (DFA) assay was used on urine specimen which were positive by PCR to confirm the positive results. Results Overall C. trachomatis infection tested by both PCR and DFA was present in 1.6% (16/1000) of asymptomatic pregnant women. A total of 200 pools of urine samples were tested and 20 pools were positive for C. trachomatis . When these pools were tested individually, 20 (10%) samples were positive for CT (In one pool, 2 samples were positive and one pool was false positive). Four samples were negative by DFA. Pooling of urine samples saved 70% of reagent costs in our study. Conclusions The study shows C. trachomatis infection was present in 1.6% of pregnant women which indicates low prevalence of infection in northern India. Pooling of urine samples saved labour, cost (70% reduction) and time in screening large number of samples in resource-limited settings. Disclosure of interest statement None (No conflict of interest). The study was funded by Indian Council of Medical Research, New Delhi. No pharmaceutical grants were received in the development of this study.

Abstract 2963: 5-hydroxymethylcytosine alterations at H3K9me3 marked genomic regions serve as potential biomarker for renal cell carcinoma patients

Abstract Background: Epigenetic alterations are frequently encountered in many malignancies. Control of DNA methylation is thought to play a critical role in the global epigenetic reprogramming observed during development and carcinogenesis. DNA demethylation is initiated by the transition from 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). While 5mC patterns are relatively well characterized in many malignancies, not much is known about 5hmC patterns and the potential usefulness as biomarkers. We thus sought out to identify 5hmC alterations in renal cell carcinoma (RCC) and assess their potential usefulness as urine biomarkers. Results: We performed genome-wide 5hmC MethylCap-seq on one pooled RCC tissue sample (n = 3) and the corresponding pooled matched normal kidney tissue (n = 3), as well as on one pooled urine sample obtained from RCC patients (n = 52) and one pooled urine sample obtained from control patients without malignancy (n = 65). Global 5hmC levels were dramatically reduced in RCC tissues compared to matched normal adjacent kidney tissues, and in urine samples compared to tissue samples. Assessing histone marked regions we found 5hmC levels to be highly enriched in H3K9me3 marked repressive genomic regions of RCC tissue compared to normal adjacent tissues. Given the low 5hmC signal in these regions in normal tissues, this difference was also clearly identified comparing urine samples from RCC patients to control patients without RCC. Conclusions: We characterized the 5hmC distribution of RCC and normal human renal tissue as well as of urine samples from RCC patients and control patients without RCC. We identified dramatic genome-wide 5hmC changes to occur during carcinogenesis, which have potential for development as non-invasive urine biomarkers. Citation Format: Wei Meng, Tim Lautenschlaeger, David Frankhouser, Zhenqing Ye, Alexander Huebner, Victor Jin, Pearlly Yan, Arnab Chakravarti. 5-hydroxymethylcytosine alterations at H3K9me3 marked genomic regions serve as potential biomarker for renal cell carcinoma patients. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2963. doi:10.1158/1538-7445.AM2015-2963

Urinary extracellular vesicles as reservoirs of altered proteins during the pathogenesis of polycystic kidney disease.

Recent findings indicate that urinary extracellular vesicles (EVs) might reflect the pathophysiological state of urinary system; and that EVs-induced ciliary signaling is a possible mechanism of intercellular communication within the tract. Here, we aimed to analyze the protein expression of urinary EVs during autosomal dominant polycystic kidney disease (ADPKD). EVs were isolated from pooled urine samples of healthy control and ADPKD patients at two different stages of the disease and under tolvaptan treatment using the double-cushion ultracentrifugation method. Proteins were identified and quantified by iTRAQ and multidimensional protein identification technology (MudPIT)-based quantitative proteomics. Quantitative analyses identified 83 differentially expressed EV proteins. Many of these have apical membrane origin and are involved in signal transduction pathways of primary cilia, Ca(2+) -activated signaling, cell-cycle regulation, and cell differentiation. The reduced AQP-2 and the increased APO-A1 levels observed in all ADPKD-affected groups may reflects the impaired renal concentrating capability of these patients and correlated with estimated glomerular filtration rate decline. The levels of some upregulated proteins involved in Ca(2+) -activated signaling declined upon tolvaptan treatment. The results obtained suggest that the quantitative proteomics of urinary EVs might be useful to monitor proteins difficult to access noninvasively, and thus advance our understanding of urinary tract physiology and pathology.

Extending analysis of environmental pollutants in human urine towards screening for suspected compounds

Today there is a large difference in the number of chemicals of commerce and the number of chemicals being monitored in environmental and human samples. During the last decades suspect screening methods have been developed to increase the number of monitored analytes. Peaks detected during high resolution mass spectrometry full scan measurements are compared to a list of suspect chemicals with known exact masses. These methods, however, have so far focused on environmental samples. Thus we present a method development for a suspect screening of human urine samples. The sample preparation techniques and instrumental analysis were tested by target chemicals with a wide range of properties. A combination of direct injection and QuEChERS extraction followed by liquid chromatography coupled to high resolution mass spectrometry was able to detect 33 of the 40 spiked target compounds at 30-120% absolute recovery. For suspect evaluation peaks were deconvoluted and aligned with the software MZmine followed by R script processing. Comparing detected and in-silico fragmentation, nine suspect chemicals could be tentatively identified in a pooled human urine sample and four of these were confirmed by a reference standard.

Analysis of anonymized pooled urine in nine UK cities: variation in classical recreational drug, novel psychoactive substance and anabolic steroid use.

Analysis of anonymous pooled urine samples from street urinals has been used to demonstrate time-trends in the detection of classical recreational drugs and novel psychoactive substances (NPS). This study aimed to expand this to undertake a geographical trend analysis of classical recreational drugs/NPS across UK. Samples of anonymous pooled urine were collected from street urinals that had been in place for one night in April 2014 in nine cities across the UK. Collected samples were then analysed for the presence of recreational drugs, NPS anabolic steroids using high-performance liquid chromatography coupled to high-resolution accurate mass full-scan mass spectrometry and gas chromatography coupled to electron impact ionization mass spectrometry operating in selected ion monitoring and full-scan modes. Ten classical recreational drugs, nine NPS and four anabolic steroids were detected across the nine cities; the range of detection was from 1 in Leeds to 14 in London. The most common classical drugs were cocaine (9 cities) and 3,4-methylenedioxy-methamphetamine (8 cities); the most common NPS was 4-methylmethcathinone (5 cities). In addition there was variation in the detection of NPS, with methylhexaneamine detected only in Bristol and London, piperazines (3-trifluoromethylphenylpiperazine and 1-benzylpiperazine) and pentedrone only detected in Birmingham and the cathinone methylone only detected in London. There is variability in the detection of classical recreational drugs, NPS and anabolic steroids across UK, likely reflecting variation in their use. This technique can be used to supplement drug use surveys to determine geographical and time trends in the use of these substances. This is important to ensure appropriate targeting of drug-related interventions.

The effect of chronic kidney disease on the urine proteome in the domestic cat (Felis catus)

Chronic kidney disease (CKD) is a major cause of mortality in cats, but sensitive and specific biomarkers for early prediction and monitoring of CKD are currently lacking. The present study aimed to apply proteomic techniques to map the urine proteome of the healthy cat and compare it with the proteome of cats with CKD. Urine samples were collected by cystocentesis from 23 healthy young cats and 17 cats with CKD. One-dimensional sodium-dodecyl-sulfate polyacrylamide gel electrophoresis (1D-SDS-PAGE) was conducted on 4–12% gels. Two-dimensional electrophoresis (2DE) was applied to pooled urine samples from healthy cats (n = 4) and cats with CKD (n = 4), respectively. Sixteen protein bands and 36 spots were cut, trypsin-digested and identified by mass spectrometry.1D-SDS-PAGE yielded an overall view of the protein profile and the separation of 32 ± 6 protein bands in the urine of healthy cats, while CKD cats showed significantly fewer bands (P < 0.01). 2-DE was essential in fractionation of the complex urine proteome, producing a reference map that included 20 proteins. Cauxin was the most abundant protein in urine of healthy cats. Several protease inhibitors and transport proteins that derive from plasma were also identified, including alpha-2-macroglobulin, albumin, transferrin, haemopexin and haptoglobin. There was differential expression of 27 spots between healthy and CKD samples (P < 0.05) and 13 proteins were unambiguously identified. In particular, increased expression of retinol-binding protein, cystatin M and apolipoprotein-H associated with decreased expression of uromodulin and cauxin confirmed tubular damage in CKD cats suggesting that these proteins are candidate biomarkers.

A matrix-induced ion suppression method to normalize concentration in urinary metabolomics studies using flow injection analysis electrospray ionization mass spectrometry

Normalizing the total urine concentration is important for minimizing bias in urinary metabolomics analysis comparisons. In this study, we report a matrix-induced ion suppression (MIIS)-based method to normalize concentration using flow injection analysis coupled with electrospray ionization mass spectrometry (FIA-ESI-MS). An ion suppression indicator (ISI) was spiked into urine samples, and the intensity of the extracted ion chromatogram (EIC) for ISI in a urine matrix was subtracted by the EIC for a blank solution and used to calculate the extent to which the signal was reduced by the urine matrix. A series dilution of pooled urine samples was used to correlate the urine concentration and level of ion suppression for ISI. A regression equation was used to estimate the relative concentration of unknown urine samples. The MIIS method was validated for linearity, precision and accuracy. We obtained a good correlation using a quadratic regression model for 1- to 32-fold urine dilutions (R2=0.998). The reproducibility (n=4) and intermediate precision (n=3) were below 5% RSD, and the accuracy ranged from 97.15% to 102.10%. The established method was used to estimate the relative concentrations of 16 urine samples, and the results were compared with commonly used normalization methods. Pearson’s correlation test was used to demonstrate that the MIIS method correlated highly with the creatinine and osmolarity methods; the correlation coefficients were 0.93 and 0.99, respectively. We successfully applied this method to a urinary metabolomics study on breast cancer. This study demonstrated the MIIS method is simple, accurate and can contribute to data integrity in urinary metabolomics studies.

Variations of human urinary proteome.

The study on dynamic analysis of human urinary proteome is the foundation that we discriminate certain various urinary proteins as potential bio-marker derived from the disease itself or normal physiological change. In our results, based on RPLC-MS/MS and spectral count to study pooled and individual urine samples and other researchers' studies, it can be known that the content of many urinary proteins maintain relatively stable. We have reason to believe that the relatively stable urinary protein is a very valuable resource as biomarkers. Many similar proteins such as prostaglandin-H2 D-isomerase and apolipoprotein D proteins have been proved our hypothesis. The following field, the number, preservation and treatment methods of urine sample, the standardization of analysis method and data processing, and suitable quantitative method, is ought to the focus of future study.

Abstract 889: MicroRNA-21-5p upregulation in urine samples serves as novel biomarkers for early stage renal cell carcinoma patients diagnosis

Abstract Early prevention of renal cell carcinoma needs a reliable and robust bioassay to evaluate kidney cancer patients. As a novel class of regulatory molecules in cellular activity, the recent studies showed that microRNAs had tissue-specific patterns and were able to distinguish the cancer from benign disease. We explored the diagnostic value of urine microRNAs from a cohort of 160 individuals: 80 patients with renal clear cell carcinoma and 80 normal control individuals. Material and methods: The renal clear cell carcinomas cohort included 63% stage I cases, 10% stage II cases, 19% stage III cases, 7% stage IV cases, 1% unknown cases. Normal control cohort included 34% diverticulosis cases, 15% bariatric surgery cases, 14% diverticulitis cases, 15% hernia surgery cases, 10% hemorrhoids cases and 12% other non-cancer conditions. Every 10 urine samples were pooled together and subjected to microRNA extraction. The Norgen Biotek urine microRNA purification kit was used for total microRNA extraction (including free floating microRNAs and microRNAs from exfoliated cells) in the pooled urine samples. Urine microRNA expression profiling was performed using nCounter miRNA Expression Assay. After ligation and purification, hybridized microRNAs sequences were label by specific color codes and quantified using nCounter Digital Analyzer, then the data were normalized to the sum of the microRNAs within each pooled sample before statistic analysis. Result: comparing to normal control urine samples, microRNA-21-5p expression showed upregulation in kidney urine samples, which is consistent with TCGA kidney cancer tissue profiling results. Some recent studies also demonstrated that microRNA-21 may act as an oncomir in prostate, lung and colorectal cancers. We also observed that microRNA-1268a and microRNA-549 were highly expressed in urine samples from renal cell carcinoma patients. Conclusion: These findings indicate that in urine microRNA-21-5p may serve as a potential molecular marker for renal cell carcinoma and provide a new approach in the diagnosis of kidney cancer. Note: This abstract was not presented at the meeting. Citation Format: Wei Meng, Hansjuerg Alder, Kirsteen Maclean, Simon Kirste, Petra Stegmaier, Anca Grosu, Arnab Chakravarti, Tim Lautenschlaeger. MicroRNA-21-5p upregulation in urine samples serves as novel biomarkers for early stage renal cell carcinoma patients diagnosis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 889. doi:10.1158/1538-7445.AM2014-889

Disposition and metabolic profiling of [(14)C]cerlapirdine using accelerator mass spectrometry.

Cerlapirdine (SAM-531, PF-05212365) is a selective, potent, full antagonist of the 5-hydroxytryptamine 6 (5-HT6) receptor. Cerlapirdine and other 5-HT6 receptor antagonists have been in clinical development for the symptomatic treatment of Alzheimer's disease. A human absorption, distribution, metabolism, and excretion study was conducted to gain further understanding of the metabolism and disposition of cerlapirdine. Because of the low amount of radioactivity administered, total (14)C content and metabolic profiles in plasma, urine, and feces were determined using accelerator mass spectrometry (AMS). After a single, oral 5-mg dose of [(14)C]cerlapirdine (177 nCi), recovery of total (14)C was almost complete, with feces being the major route of elimination of the administered dose, whereas urinary excretion played a lesser role. The extent of absorption was estimated to be at least 70%. Metabolite profiling in pooled plasma samples showed that unchanged cerlapirdine was the major drug-related component in circulation, representing 51% of total (14)C exposure in plasma. One metabolite (M1, desmethylcerlapirdine) was detected in plasma, and represented 9% of the total (14)C exposure. In vitro cytochrome P450 reaction phenotyping studies showed that M1 was formed primarily by CYP2C8 and CYP3A4. In pooled urine samples, three major drug-related peaks were detected, corresponding to cerlapirdine-N-oxide (M3), cerlapirdine, and desmethylcerlapirdine. In feces, cerlapirdine was the major (14)C component excreted, followed by desmethylcerlapirdine. The results of this study demonstrate that the use of the AMS technique enables comprehensive quantitative elucidation of the disposition and metabolic profiles of compounds administered at a low radioactive dose.