Healthy Human Urine Research Articles

Neutrophil extracellular traps protect the kidney from ascending infection and are required for a positive leukocyte dipstick test.

Lower urinary tract infection (UTI) is common but only rarely complicated by pyelonephritis. However, the mechanisms preventing extension to the kidney are unclear. Here, we identified neutrophil extracellular traps (NETs) in healthy human urine that provide an antibacterial defense strategy within the urinary tract. In both in vivo murine models of UTI where uropathogenic E. coli are inoculated into the bladder and ex vivo human urine models, NETs interacted with uromodulin to form large webs that entrapped the bacteria. Peptidyl arginine deiminase 4 (PADI4) inhibition in mice blocked NETosis and resulted in progression of cystitis into pyelonephritis, suggesting that NETosis of urinary neutrophils acts to prevent bacterial ascent into the kidney. Analysis of UK Biobank data revealed that genetic variants in PADI4 that associated with increased risk of rheumatoid arthritis in multiple genome-wide association studies were consistently associated with reduced susceptibility to UTI. Last, we showed that urine dipstick testing for leukocyte esterase was negative in the presence of intact blood neutrophils but became positive when neutrophils were stimulated to NET, and this could be prevented by selective PADI4 inhibition, demonstrating that this test does not detect absolute neutrophil count, as has long been assumed, but specifically detects neutrophils that have undergone NETosis. These findings highlight the role of NETosis in preventing ascending infections in the urinary tract and improve our understanding of one of the most common clinical tests in medicine.

Human urine-derived stem cells: potential therapy for psoriasis-like dermatitis in mice

Over the past decade, significant advancements in stem cell research led by mesenchymal stem cells (MSCs) have facilitated their practical application in clinical settings, including inflammatory skin diseases. Urine-derived stem cells (USCs) are obtained from healthy human urine in a noninvasive approach with properties similar to mesenchymal stem cells (MSCs). However, the therapeutic potential of USCs for inflammatory skin diseases has not yet been fully explored. Herein, we report the therapeutic effects of USCs-derived culture supernatants on mice with psoriasis-like dermatitis using our originally established human USCs model. We examined the isolation of USCs from human urine using a simple centrifugation process. Cell markers related to MSCs-like cell were positive for CD29, CD44, CD73, CD90, and negative for HLA-DR, CD34, and CD45 by FACS analysis. Differentiation assays revealed that the cells possessed the capability to differentiate into adipocytes, chondrocytes, and osteocytes. USCs-conditioned medium (CM) treatment significantly suppressed the severity of dermatitis in imiquimod (IMQ)-treated psoriasis mice model. Histopathological examination revealed that USCs-CM treatment attenuated epidermal thickness and the numbers of infiltrating inflammatory cells, including neutrophils, T-cells, and macrophages in dermatitis-affected areas in IMQ-treated psoriasis mice. Furthermore, USCs-CM treatment decreased mRNA levels of IL-17A, IL-17F, and IL-23p19 was reduced in dermatitis area. In summary, our findings revealed new potential strategies for utilizing USCs and USCs-CM as therapeutic agents for inflammatory skin diseases, including psoriasis.

Determination of Alzheimer's Drugs in a Human Urine Sample by Different Chemometric Methods: Chemometric Determination of Alzheimer's Drugs.

In this study, spectrophotometric determination of donepezil and rivastigmine in healthy human urine samples was carried out by the statistical method. Partial least squares (PLS) and principal component regression (PCR) from multivariate calibration methods were used to evaluate the data obtained from the UV-Vis spectroscopy analysis of the urine sample. Mixtures of each early substance were prepared prior to urine sample analysis, and simultaneous determination of donepezil and rivastigmine was performed on the established chemometric model without any prior separation. The calibration curves of each drug were analyzed, and linearity values were also analyzed. For donepezil and rivastigmine, they were 0.9989 and 0.9997, respectively, and were linear over the concentration range of the synthetic mixture. When both chemometric methods (PLS and PCR) were evaluated in terms of accuracy and reproducibility, very high recoveries and small standard deviations were determined. In the PLS method, the standard error of prediction (SEC), the sum of the prediction residual errors (PRESS), the limit of quantitation (LOQ), and the limit of detection (LOD) values were 0.015, 0.0030, 0.067, 0.24, 0.018, 0.0042, 0.089, and 0.301 for donepezil and rivastigmine, respectively. In the PCR method, SEC, PRESS, LOD, and LOQ values are 0.016, 0.0054, 0.066, and 0.23 for donepezil and 0.022, 0.0062, 0.091, and 0.300 for rivastigmine. Chemometrics is used for speed, simplicity, and reliability. The proposed methods have been successfully applied to a sample of urine.

Development of a rapid, sensitive, and selective LC-MS/MS method for quantifying curcumin levels in healthy human urine: Effect of pepper on curcumin bioavailability.

Curcumin (CCM), a culinary spice, is widely consumed for its health benefits for managing oxidative and inflammatory conditions, metabolic syndrome, arthritis, and hyperlipidemia. However, due to its extensive metabolism, the oral bioavailability of CCM is very low. In this study, we developed a rapid, sensitive, and selective assay to examine the hypothesis that piperine improves CCM bioavailability after piperine co-ingestion. We developed a selective, sensitive, and robust LC-MS/MS method to quantify CCM in human urine. The method was linear over a concentration range 0.625-40 ng/mL with LLOQ and LLOD of 0.625 ng/mL and 0.312 ng/mL, respectively. Healthy volunteers have consumed test meals of CCM as turmeric powder with and without black pepper with 1 week wash out. Urine samples were collected for 24 hours and analyzed for CCM excretion. Black pepper increased CCM half-life from 2.2 ± 0.79 h (CCM alone) to 4.5 ± 0.80 h (CCM + pepper). The CCM 24-h urinary excreted amount was higher in individuals consuming CCM + pepper (218.14 ± 94.98 μg) than those who received CCM only (49.45 ± 12.94 μg). This preliminary study indicates that piperine significantly increased CCM oral absorption, reduced systemic clearance, and improved bioavailability.

Proteolytic Activity against the Distal Polybasic Tract of the Gamma Subunit of the Epithelial Sodium Channel ENaC in Nephrotic Urine.

Experimental nephrotic syndrome in mice leads to proteolytic activation of the epithelial sodium channel ENaC, possibly involving the distal polybasic tract of its γ-subunit (183RKRK). We sought to determine if urine samples from both nephrotic mice and a cohort of patients with acute nephrotic syndrome contain a specific proteolytic activity against this region of γ-ENaC. A peptide substrate consisting of amino acids 180-194 of murine γ-ENaC was N-terminally coupled to a fluorophore, yielding AMCA-FTGRKRKISGKIIHK. The substrate was incubated with nephrotic urine samples from mice as well as patients with or without the serine protease inhibitor, aprotinin. The digested peptides were separated on a reverse phase HPLC and detected with a fluorescence detector (350/450 nm). Peptide masses of the peaks were determined with a MALDI-TOF mass spectrometer. In addition, urinary proteolytic activity was quantitated using AMC-coupled substrates reflecting different cleavage sites within the polybasic tract. No significant proteolytic activity against the substrate was found in the urine of healthy humans or mice. Incubation with urine samples of nephrotic patients (n = 8) or mice subjected to three different models of experimental nephrotic syndrome (n = 4 each) led to cleavage of the substrate within the polybasic tract prevented by the serine protease inhibitor aprotinin. The most dominant cleavage product was FTGRKR in both species, which was confirmed using quantitative measurements with FTGRKR- AMC. Nephrotic urine from both humans and mice contains aprotinin-sensitive proteolytic activity against the distal polybasic tract of γ-ENaC, reflecting excretion of active proteases in the urine or proteasuria.

Urine protects urothelial cells against killing with nanosecond pulsed electric fields

The quest for safe and effective ablation resulted in the development of nanosecond pulsed electric fields (nsPEF) technology for tumor treatment. For future applications of nsPEF in urothelial cancer treatment, we evaluated the effect of urine presence at the ablation site. We prepared artificial urine (AU) with compounds commonly present in the healthy human urine at physiological concentrations. We compared nsPEF cytotoxicity for cancerous (T24) and non-cancerous (SV-HUC-1) human urothelial cell lines pulsed either in the AU or in a physiological solution (PS). Cell monolayers were exposed to trains of 300-ns, 10-Hz pulses using a two-needle electrode assembly placed orthogonal to the monolayer. The assembly produced the electric field gradually weakening with the distance from the electrodes. The electric field which killed 50 % of cells (LD50) was measured by staining with propidium iodide and matching the stained area with the simulated electric field strength. nsPEF exposure in PS was more cytotoxic to cancer cells. The AU protected both healthy and cancer urothelial cells, increasing their LD50 1.4 and 1.6 times, respectively. Omitting urea from the AU reduced the LD50 for healthy and cancer urothelial cells. Testing the role of other AU components, we found that it was the high concentration of phosphates what also rendered the protective effect of the AU. Our findings suggest that the nsPEF ablation of bladder cancer will be less efficient if the bladder is filled with urine.

Development of an innovative flexible paper-based methanol fuel cell (PB-DMFC) sensing platform – Application to sarcosine detection

This work describes for the first time a paper-based direct methanol fuel cell platform (PB-DMFC) that functions as an energy source and biosensor, assembled on a simple paper substrate for point-of-care (POC) applications, targeting sarcosine as proof-of-concept.Specifically, a methanol fuel cell strip was developed from a square of Whatman paper, acting as substrate. The paper strip was treated with an impermeable agent (paraffin solution) and supported all fuel cell device components, including the electrolyte (Nafion®), anode electrode (carbon black Pt/Ru), cathode electrode (carbon black Pt), and current collectors (silver edges). All the described components formed a flexible single layer that operated in a completely passive mode by adding few microliters of a methanol solution on the anode side and by using atmospheric oxygen on the cathode side. The obtained platform had a stable electrical signal with an average OCV value of 0.45–0.55 V and a maximum power density of 20–50 µW/cm2, depending on the methanol concentration used (0.5 M–2 M). A sensing layer was built in situ on the anode electrode by electropolymerization of a solution of 3,4-ethylenedioxythiophene (EDOT) and pyrrole (Py) as monomers. The obtained PB-DMFC/biosensor was calibrated at room temperature in buffer and healthy human urine and showed linear responses from 1.0 × 10−7 to 1.0 × 10−3 M with a detection limit of 6.6 × 10−8 M. Selectivity studies evidenced signals changing within 1–10%, both in positive and negative directions. Results evidenced good reproducibility.Overall, the obtained results demonstrate a self-sufficient biosensor for the detection of sarcosine consisting of an innovative paper-based methanol fuel cell strip. This concept can open new horizons for massification of biosensors even in places with energy shortage.

Novel Electrochemical Sensors Based on L-Proline Assisted LDH for H2O2 Determination in Healthy and Diabetic Urine.

In this paper, a novel non-enzymatic modified glassy carbon (GC) sensor, of the (GC-Agpaste)-catalytic proline-assisted LDH type, for H2O2 determination was fabricated, studied, characterized and employed to determine the hydrogen peroxide content in healthy and diabetic human urine. LDH (whose composition can be schematized as [ZnIIAlIII (OH)2]+ NO3−·nH2O) is glued to glassy carbon by means of silver paste, while proline, which increases the catalytic properties of LDH, is used free in solution in the phosphate buffer. A voltametric survey was first conducted to ascertain the positive effect induced by the presence of proline, i.e., the increase of sensor sensitivity. Then a deep study of the new three-electrode amperometric proline-assisted LDH sensor, whose working electrode was of the same type as the one used to perform the cyclic voltammetry, was carried out, working at first in static air, then in a nitrogen atmosphere. Possible interferences from various substances, both oxidants and antioxidants, were also investigated. Lastly, the new amperometric sensor was successfully used to determine the H2O2 level in human urine from both healthy and diabetic subjects. The effect of proline in enhancing the properties of the sensor system was also investigated. The limit of detection (LOD) of the new catalytic sensor was of the order of 0.15 mmol L−1, working in air, and of 0.05 µmol L−1, working in nitrogen atmosphere.

The N&P Co‐doped Lotus Root Derived Carbon Materials for Highly Sensitive Electrochemical Analysis of Baicalein and Luteolin

AbstractThe application of biomass‐based carbon materials in electrochemical sensing was limited due to their few active sites. So N and P double doped biomass pyrolytic carbon materials were designed in this paper. These gained materials were characterized by a series of characterization test techniques, and used as electrode modification to construct electrochemical sensors to detect baicalein (BA) and luteolin (LU). Under the best test condition, the minimum detectability of BA and LU was (7.8±0.25)×10−9 mol/L and (7.6±0.24)×10−9 mol/L (S/N=3), respectively. And the sensor performed well in the Shuanghuanglian oral liquid and the healthy human urine samples.

Kidney-Derived Methylated PAX2 Sequences in the Urine of Healthy Subjects as a Convenient Model for Optimizing Methylation-Based Liquid biopsy.

Although urine-based liquid biopsy has received considerable attention, there is a lack of a simple model to optimize assay parameters, including cell-free DNA (cfDNA) extraction, bisulfite modification, and bis-DNA recovery after conversion for methylation analysis in urine. The primary aim of this work was to establish a practical model by developing a quantitative methylation-sensitive PCR (qMS-PCR) assay for PAX2 based on hypermethylated PAX2 cfDNA that couldbedetected in healthy human urine. We firststudiedthe methylation status of PAX2 in kidney tissues and whole blood,followedbyanassessment ofcommercial kits for bisulfite conversion and bis-DNA recovery. Furthermore, we investigated the influence of urine storage and collection conditions on the preservation of methylated PAX2 in urine samples by qMS-PCR. As expected, PAX2 methylation was identified in urine but not in blood. Two commercial kits (CellCook and Zymo Research) had similar conversion efficiency and bis-DNA recovery. Urine storage for up to 5days did not changePAX2methylation estimates. Overall, cold storage of urine samples and the CellCook urine container maintained higher levels of methylated PAX2 compared to urine kept at room temperature and the conventional tubes, respectively. These findings highlight the importance of using the correct approaches/kits and optimizing experimental conditions as a diagnostic tool in the clinical setting. Our study provides insights on the development of urine-based liquid biopsy with DNA methylation as a universal biomarker.

Polypyrrole Based Molecularly Imprinted Polymer Platform for Klebsiella pneumonia Detection

The present work describes the synthesis of molecular imprinting polymer (MIP) and electrochemical sensing of Klebsiella pneumonia (K. pneumonia) bacteria by electrochemical technique. K. pneumonia has far reached ill effects on the human body, hence it is essential to monitor its levels. A MIP platform based on polypyrrole (PPy) was developed for electrochemical sensing of K. pneumonia to monitor its levels. The developed sensor has good sensitivity (3 μA ml CFU-cm−2), a low limit of detection (LOD) of 1.352 CFU ml−1 in the linear detection range of 1 to 105 CFU per ml. The molecular imprinting was carried out by polymerization of pyrrole in the presence of K. pneumonia and then removed the bacteria by ultrasonication to obtain the MIP. The fabrication of electrodes is done by electrophoretic deposition (EPD) of MIP onto the hydrolyzed ITO-coated glass surface. The detection was done by the electrochemical differential pulse voltammetry (DPV) technique. The synthesized final product is then characterized by Fourier transform infrared spectroscopy (FTIR) technique to understand its structure and confirm the successful synthesis of the desired MIP. The selectivity studies were performed against two other bacteria and different ions that are present in healthy human urine. To check the applicability in real sample studies, spiked urine samples were used.

Simultaneous electrochemical detection of gallic acid and uric acid with p-tert-butylcalix[4]arene-based coordination polymer/mesoporous carbon composite.

Design and synthesis of an efficient electrocatalyst for simultaneous determinationof gallic acid (GA) and uric acid (UA) is vital in thebiological field. Herein, we synthesized a new p-tert-butylcalix[4]arene-based metal-organic electrocatalyst (Mn-L@MC) by combining Mn-L (H4L = tetrakis[(2-biphenylcarboxyl)oxy]-p-tertbutylcalix[4]arene) and mesoporous carbon (MC) via a simple mechanical grinding method. Synergistic effect between Mn-L and MC made the Mn-L@MC composite behave high-efficiency electrocatalytic performance toward simultaneous detection of GA and UA. Under optimal experimental conditions, the Mn-L@MC-2 electrode material featured relatively wide linear range (0.5-90µM) for the two analytes, and low determination limits of 0.043µM for GA and 0.059µM for UA. The remarkable electrochemical detection behavior of Mn-L@MC-2 electrode material toward GA and UA are comparable to those known sensors containing precious metals. TheMn-L@MC-2 material exhibited highselectivity, superior reproducibility, and acceptable stability during the determinationof the two analytes. Thesensor was assembled to simultaneously detect GA and UA in healthy human urine with satisfactory recoveries.

Qualitative and quantitative proteomic and metaproteomic analyses of healthy human urine sediment

The healthy human urine sediment proteome and metaproteome are investigated, to shed light on the variations of urine sediment proteins and metaproteins associated with sex and age. Urine sediment samples are collected from 19 healthy subjects. Protein identification and quantification are performed by liquid chromatography coupled high-resolution mass spectrometry. A total of 2736 human proteins were identified, which were primarily associated with inflammatory response and energy metabolism. For the metaproteome, 65 genera were identified that were primarily involved in translation and carbohydrate metabolic processes. The median biological coefficient variation of the proteome/metaproteome of human urine sediment was 0.5/0.72, similar to the proteome of human urine supernatant. In addition, sex and age were observed to affect the proteome and metaproteome of healthy human urine sediment. The healthy human urine sediment were characterized, indicating that urine sediment might represent an alternative resource for disease research in addition to urine supernatant, but the influence of sex and age must be considered in the study design process.

Optimisation of a lozenge-based sensor for detecting impending blockage of urinary catheters

Catheter-associated urinary tract infections resulting from urease-positive microorganisms are more likely to cause a urinary catheter blockage owing to the urease activity of the microbes. Catheter blockage can be dangerous and increases the risk of severe infections, such as sepsis. Ureases, a virulence factor in Proteus mirabilis, cause an increase in urine pH - leading to blockage. An optimised biosensor “lozenge” is presented here, which is able to detect impending catheter blockage. This lozenge has been optimised to allow easy manufacture and commercialisation. It functions as a sensor in a physiologically representative model of a catheterised urinary tract, providing 6.7 h warning prior to catheter blockage. The lozenge is stable in healthy human urine and can be sterilized for clinical use by ethylene oxide. Clinically, the lozenge will provide a visible indication of impending catheter blockage, enabling quicker clinical intervention and thus reducing the morbidity and mortality associated with blockage.

Simultaneous determination of 12 lipophilic shellfish toxins in plasma and urine by ultra-high performance liquid chromatography-tandem mass spectrometry

生物样品中脂溶性贝类毒素的检测,可为食物中毒等突发公共卫生事件的流行病学调查以及中毒者的临床救治提供技术支持。目前的研究存在目标化合物少,以及方法前处理复杂、灵敏度低等问题。该研究通过优化前处理和色谱分离技术,建立了超高效液相色谱-串联质谱法测定血浆、尿液中12种脂溶性贝类毒素的方法。实验对提取试剂以及流动相的选择进行了优化,采用乙腈对尿液和血浆样品进行提取。采用Phenomenex Kinetex C18色谱柱(50 mm×3 mm, 2.6 μm)进行分离,以0.05%(v/v)氨水水溶液、90%(v/v)乙腈水溶液为流动相,以流速0.40 mL/min梯度洗脱时,12种目标化合物分离效果最好。串联质谱的离子源为电喷雾离子(ESI)源,采用多反应监测(MRM)模式检测。12种目标物的基质效应均在0.8~1.1之间,表明该前处理方法的基质干扰低,采用外标法可对化合物进行准确定量。12种贝类毒素的线性范围为0.03~36.25 μg/L,相关系数均大于0.995。尿液检测的方法定量限为0.23~0.63 μg/L,血浆检测的方法定量限为0.31~0.84 μg/L。3个加标水平的回收率为72.7%~124.1%,日内精密度为2.1%~20.0%,日间精密度为2.1%~15.3%。利用该方法检测健康人尿液和血浆样本,以及经腹腔注射12种贝类毒素的小鼠尿液和血液样本。20份健康人样本中未检出目标物,20份小鼠样本中12种贝类毒素均有检出。该方法操作简便,样品取样量少,方法灵敏高,适用于血浆和尿液中脂溶性贝类毒素的快速检测。

Cell Differentiation Agent-2 (CDA-2) Inhibits the Growth and Migration of Saos-2 Cells via miR-124/MAPK1.

BackgroundCDA-2 (cell differentiation agent 2), isolated from healthy human urine, exerts antitumor effects in multiple types of cancer cells. However, its role in osteosarcoma has not been studied.MethodsThe MTT assay was used to examine the cell proliferation rate. A colony formation assay was used to examine cell growth. The Transwell assay was used to examine cell migration ability. A real-time PCR assay was used to examine the expression levels of miR-124 and MAPK1. A Western blot assay was used to examine protein expression levels. MAPK1 was selected as a possible target of miR-124, and the targeting relationship was examined by a luciferase reporter assay.ResultsWe revealed that CDA-2 decreased the growth, migration and invasion ability of the osteosarcoma cell line Saos-2. Further study revealed that CDA-2 elevated the expression level of miR-124. MAPK1 was identified as a downstream target of miR-124. Knockdown of miR-124 or overexpression of MAPK1 counteracted CDA-2’s effects on cell growth and invasion.ConclusionOur data revealed that the miR-124/MAPK1 axis mediated CDA-2’s function in Saos-2 cells. CDA-2 can be used as a new treatment strategy for osteosarcoma.

Giant magnetoresistive biosensors for real-time quantitative detection of protease activity

Proteases are enzymes that cleave proteins and are crucial to physiological processes such as digestion, blood clotting, and wound healing. Unregulated protease activity is a biomarker of several human diseases. Synthetic peptides that are selectively hydrolyzed by a protease of interest can be used as reporter substrates of unregulated protease activity. We developed an activity-based protease sensor by immobilizing magnetic nanoparticles (MNPs) to the surface of a giant magnetoresistive spin-valve (GMR SV) sensor using peptides. Cleavage of these peptides by a protease releases the magnetic nanoparticles resulting in a time-dependent change in the local magnetic field. Using this approach, we detected a significant release of MNPs after 3.5 minutes incubation using just 4 nM of the cysteine protease, papain. In addition, we show that proteases in healthy human urine do not release the MNPs, however addition of 20 nM of papain to the urine samples resulted in a time-dependent change in magnetoresistance. This study lays the foundation for using GMR SV sensors as a platform for real-time, quantitative detection of protease activity in biological fluids.

An Integrated Mass Spectroscopy Data Processing Strategy for Fast Identification, In-Depth, and Reproducible Quantification of Protein O-Glycosylation in a Large Cohort of Human Urine Samples.

Protein O-glycosylation has long been recognized to be closely associated with many diseases, particularly with tumor proliferation, invasion, and metastasis. The ability to efficiently profile the variation of O-glycosylation in large-scale clinical samples provides an important approach for the development of biomarkers for cancer diagnosis and for therapeutic response evaluation. Therefore, mass spectrometry (MS)-based techniques for high throughput, in-depth and reliable elucidation of protein O-glycosylation in large clinical cohorts are in high demand. However, the wide existence of serine and threonine residues in the proteome and the tens of mammalian O-glycan types lead to extremely large searching space composed of millions of theoretical combinations of peptides and O-glycans for intact O-glycopeptide database searching. As a result, an exceptionally long time is required for database searching, which is a major obstacle in O-glycoproteome studies of large clinical cohorts. More importantly, because of the low abundance and poor ionization of intact O-glycopeptides and the stochastic nature of data-dependent MS2 acquisition, substantially elevated missing data levels are inevitable as the sample number increases, which undermines the quantitative comparison across samples. Therefore, we report a new MS data processing strategy that integrates glycoform-specific database searching, reference library-based MS1 feature matching and MS2 identification propagation for fast identification, in-depth, and reproducible label-free quantification of O-glycosylation of human urinary proteins. This strategy increases the database searching speeds by up to 20-fold and leads to a 30%-40% enhanced intact O-glycopeptide quantification in individual samples with an obviously improved reproducibility. In total, we identified 1300 intact O-glycopeptides in 36 healthy human urine samples with a 30%-40% reduction in the amount of missing data. This is currently the largest dataset of urinary O-glycoproteome and demonstrates the application potential of this new strategy in large-scale clinical investigations.

Cyanidin-3-glucoside as a possible biomarker of anthocyanin-rich berry intake in body fluids of healthy humans: a systematic review of clinical trials.

ContextAnthocyanins are phenolic compounds found in berries. They exhibit promising health benefits in humans, but no accurate biomarkers of berry intake have been identified thus far.ObjectiveThe aim of this systematic review is to propose a biomarker of anthocyanin-rich berry intake in human plasma and urine.Data SourcesPubMed and Cochrane databases were searched from January 2008 to January 2019.Study SelectionDatabases were searched for human intervention studies that assessed the presence of anthocyanins in human body fluids using high-throughput techniques. Non-English articles and studies publishing targeted analyses were excluded.Data ExtractionTen clinical trials, in which 203 phenolic compounds were identified, were included and assessed qualitatively. The following criteria were used to identify biomarkers of berry intake: frequency, plausibility, dose-response, time response, robustness, reliability, stability, analytical performance, and reproducibility. Sensitivity and specificity of potential biomarkers were determined by the receiver operating characteristic curve.ResultsOf the 203 phenolic compounds identified in human samples, the anthocyanin cyanidin-3-glucoside was the molecule found most frequently in urine (58.06%) and plasma (69.49%). Cyanidin-3-glucoside fulfills the essential criterion of plausibility as well as the dose-response, time response, stability, and analytical performance criteria. Its positive predictive value is 74% (P = 0.210) in plasma, which is acceptable, and 61.7% (P = 0.402) in urine.ConclusionsCurrent evidence suggests that cyanidin-3-glucoside is a potential biomarker of anthocyanin-rich berry intake in plasma and urine of healthy humans.PROSPERO registration numberCRD42018096796.

Detection of Kappa Light Chain Protein in Human Urine by Surface Plasmon Resonance

Ingredients of urine proteins are complex, and different types of urinary proteins are usually associated with different diseases. Light chain proteins are related to neoplastic diseases, which might be misdiagnosed as nephropathia. Accurate detection of urine light chain proteins in urine is very important for early diagnosis of multiple myeloma and other diseases. Traditional methods for detecting urinary light chain proteins are of low sensitivities, complex processes and high costs. Surface plasmon resonance (SPR) is a sensitive, real-time and label-free method which is suitable for studying protein-molecule interactions. In this paper, SPR methods were used to detect kappa light chain proteins through direct assay method. Kappa light chain protein antibodies with a pH value of 5.0 were successfully immobilized to the sensor chip in one channel while another was used as a reference channel. Detection limit of kappa light chain proteins was estimated to be 0.1 μg/mL through direct assay method in standard solution. Healthy and patient human urine samples were also tested, which showed different SPR response signals. It indicated that SPR could be used as a fast and sensitive method in quantitative detection of urinary kappa proteins.