Simultaneous Blood Samples Research Articles

Performance of StatSensor Point-of-Care Device for Measuring Creatinine in Patients With Chronic Kidney Disease and Postkidney Transplantation.

Background:The StatSensor is a point-of-care device which measures creatinine in capillary whole blood. Previous studies reported an underestimation of the creatinine measurements at high creatinine concentrations and were performed in the prestandardization era for creatinine.Objective:This accuracy-based study evaluates the use of this device in kidney-transplanted patients and those with chronic kidney disease (CKD).Design:Cross-sectional diagnostic accuracy study.Setting:Nephrology outpatient clinic in an urban tertiary center.Participants:Adults with CKD or a functioning kidney transplant.Measurements:Duplicate StatSensor creatinine measurements were performed on capillary whole blood samples collected by direct fingerstick and SAFE-T-FILL collection device. Results were compared with simultaneous venous blood sampling for serum and plasma creatinine measured by an enzymatic method on the Roche Integra 400 mainframe analyzer with traceability to the ID-GC-MS (isotope dilution gas chromatography mass spectrometry) reference method.Methods:Deming regression, Pearson correlation coefficient, and Bland-Altman analysis were used to assess accuracy and comparability between capillary whole blood measured by StatSensor and plasma creatinine measured by routine analyzer with traceability to the reference method. Estimated glomerular filtration (eGFR) rates were calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and concordance with Kidney Disease Improving Global Outcomes (KDIGO) CKD stage classification was evaluated.Results:There were 60 participants (mean age = 61.9 ± 15.0 years, 55% men, 33% transplant, mean plasma creatinine = 137 ± 59 µmol/L). Bland-Altman analysis indicated a positive mean bias of 12.7 µmol/L between StatSensor fingerstick creatinine measurement and plasma creatinine. Comparison of eGFR (CKD-EPI) calculated from the StatSensor fingerstick creatinine versus plasma creatinine showed misclassification across all KDIGO CKD stages. Postanalytical correction of the bias did not improve misclassifications. The use of mean of duplicate StatSensor creatinine results did not improve performance compared with the use of singlet results.Limitations:Single center, limited participant numbers.Conclusions:The results of our study suggest that the limiting characteristics of the StatSensor device are not only bias, but also imprecision. The level of imprecision observed may influence clinical decision-making and limit the usefulness of StatSensor as a CKD screening tool. If choosing to utilize it for either screening for or monitoring CKD, it is essential that clinicians understand the limitations of point-of-care devices and apply this knowledge to test interpretation.

Relationship between vasospasm and serum chromogranin a levels in an animal subarachnoid haemorrhage model

Aim In that study, searching Chromogranin A levels on vasospasm in experimental subarachnoid heamorrhage (SAH) model was aimed. Material and methods Sixteen Wistar Albino male rats were used in study. Two groups are formed; first was consisting of 8 rats that experimental SAH was performed on them, second group was control group that nothing was done. Animals were sacrified fourtyeight hours later subarachnoid heamorrhage was occured. Peripheral venous blood samples were taken from the experimental group before SAH formation, 15 minutes, 75 minutes after experimental SAH formation and 48 hours as peak of vasospasm. Simultaneous peripheral venous blood samples were also collected from the control group. Blood samples were biochemically evaluated after centrifugation and serum Chromogranin A levels were studied. Results Serum chromogranin A levels increased statistically significant (p 0,05) at the 15th minute after SAH, as the samples obtained from the experimental and control groups were anticipated as a result of the statistical analysis of the data after the biochemical examinations. Conclusion In all these findings, we concluded that Chromogranin A could be used as a marker for the investigation of endocrine stress in the early period of post-SAH vasospasm and it could be proved by more studies.

Serum concentrations of heavy metals in women with endometrial polyps

Endometrial polyps are one of the common reasons of abnormal uterine bleeding in women. Industrialisation, urbanisation and increased air pollution cause increased heavy metal exposure. Heavy metals that have oestrogenic effects in human body are named as metalloestrogens. The aim of this study was to investigate the serum metalloestrogen levels such as copper (Cu), zinc (Zn), aluminium (Al), lead (Pb), nickel (Ni) and Cu/Zn ratio and their possible relationship with the occurrence of endometrial polyps. Eighty women with abnormal uterine bleeding were divided into two groups: 40 women diagnosed with endometrial polyp (study group) and 40 women without endometrial polyp (control group). Ages, body mass indices, smoking behaviours, drinking water choices, chronic diseases and intrauterine device histories were noted for all patients. Blood levels of Cu, Zn, Al, Pb, Ni and Cu/Zn ratio were analysed by inductively coupled plasma-mass spectrometry method for both groups. No statistically significant differences were observed in terms of serum median levels of Cu and Pb between the study and the control groups. The serum median levels of Zn, Ni and Al were found to be statistically lower in the study group when compared with the control group. The Cu/Zn ratio was statistically higher in the study group. High Cu/Zn ratio, as a biomarker of oxidative stress, suggests the role of oxidative stress in etiopathogenesis of endometrial polyps.IMPACT STATEMENTWhat is already known on this subject? Studies demonstrate that oestrogen and progesterone play an important role in pathogenesis of endometrial polyps. Inorganic heavy metal ions that bind and activate oestrogen receptors are referred to as ‘metalloestrogens’. Apart from toxic effects, metalloestrogens have been linked to the aetiology of oestrogen-dependent diseases such as breast and endometrium cancer and endometriosis. However, serum levels of heavy metals were not investigated in a large group of endometrial polyp patients.What do the results of this study add? This is the first study investigating the serum levels of heavy metals in a large group of endometrial polyp patients. We did not observe any increased serum levels of heavy metals in endometrial polyp patients. Our results might suggest that oestrogenic heavy metal exposure has no role in the appearance of endometrial polyps. However, increased Cu/Zn ratio due to low serum levels zinc suggests oxidative stress might play a role in endometrial polyps.What are the implications of these findings for clinical practice and/or further research? Further research of heavy metals in endometrial polyps with simultaneous blood and tissue samples could show the precise effect of environmental exposure of metalloestrogens in aetiopathogenesis of endometrial polyps.

Abstract 562: Comprehensive Arteriovenous Metabolomics in the Human Heart

Introduction: Despite broad interest in the role of metabolism in the pathogenesis of heart failure, a definitive account of fuel use by the beating human heart in situ is lacking. We therefore determined the uptake and release of over 270 metabolites by simultaneous sampling of arterial, coronary sinus, and femoral venous blood in 100 patients. Methods: We enrolled 100 patients (60% male, 12% diabetic, age = 63.6 +/- 13.5 years, BMI = 29.75 +/- 6.1, EF = 57.14 +/- 6.48) undergoing ablation of atrial fibrillation. We used liquid chromatography-mass spectrometry to quantify over 270 metabolites in plasma from coronary sinus, femoral vein, and arterial blood. We also measured O 2 and CO 2 concentration, as well as atrial pressure. Results: We detected uptake or release of 77 metabolites by the heart and 136 metabolites across the leg (p <0.05 after Benjamini-Hochberg correction). We determined the cardiac extraction of all major fuel sources, including 29 fatty acids, 11 amino acids, lactate, acetoacetate, and 3-hydroxybutyrate. Several patterns emerge: first, while the leg extracts glucose (FV/A = 0.95, q = 4.7x10-14) and releases lactate (FV/A = 1.11, q = 2.87x10-14), the heart extracts lactate (CS/A = 0.95, q = 3.77x10-9) and neither extracts nor secretes glucose. Second, while the leg releases nearly all fatty acid and amino acid species, the heart consumes most fatty acids and certain non-essential amino acids. Third, extraction of unsaturated acylcarnitines correlates with left atrial pressure (p<0.01). Finally, we find a significant positive correlation between myocardial O2 consumption and extraction of ketones (p < 0.01), but not other major cardiac fuels. Conclusion: We present the most comprehensive study to date of metabolite use and secretion by the human heart. We find the heart to be an avid consumer of fatty acids and ketone bodies, but less so of glucose and essential amino acids. Consumption of ketones increases with O2 consumption, suggesting that ketones may be a preferential fuel source under high work loads. Extraction of certain acylcarnitines increases with left atrial pressure, indicating metabolic reprogramming under high filling pressures. In summary, we provide the first comprehensive model of fuel use by the beating human heart in situ.

COMBINATION OF CENTRAL VENO-ARTERIAL CARBON DIOXIDE GAP WITH ARTERIO-VENOUS OXYGEN CONTENT DIFFERENCE DURING RESUSCITATION AS A PREDICTOR OF MULTI-ORGAN DYSFUNCTION IN SEPTIC PATIENTS

Background: Venous-to-arterial carbon dioxide difference (PvaCO2) the Pcv-aCO2/arterial-to-venous oxygen content difference (Ca-cvO2) ratio may reflect the adequacy of blood flow during shock states. We sought to test whether the development of Pv-aCO2 PcvaCO2/ arterial-to-venous oxygen content difference ratio during the very early phases of resuscitation is related to multi-organ dysfunction and outcomes in a population of septic patients resuscitated targeting the usual oxygen-derived and hemodynamic parameters. Aim of the Work: To evaluate the changes in central venous-toarterial carbon dioxide difference (Pcv-aCO2 gap) and in PcvaCO2/ arterial-to-venous oxygen content difference (Ca-cvO2) ratio [Pcv-aCO2/Ca-cvO2 ratio] during the early resuscitation in sepsis and septic shock as a predictor for development of multi-organ dysfunction and mortality. Patients and Methods: This prospective observational study wasperformed in a 24-bed mixed ICU in a university-affiliated hospital. We examined all septic patients with a new episode admitted to the emergency room or proceeding from clinical wards during a 24-month period. After approval by Ethical Medical Committee and obtaining informed consent, simultaneous blood samples were collected from the central venous line and the arterial catheter for obtaining venous and arterial gases respectively at T0, and 6 hours (T6), 12 hours (T12) and 24 hours (T24) later. Patients were classified twice; the first one into groups (A and B) according to PcvO2 gap and the second one into groups (C and D) according to Pcv-aCO2/Ca-cvO2 ratio. Group (A) Decreasing PcvaCO2 (high at T0, declining at T6), Group (B) Persistently high PcvaCO2 (high at T0 and T6), Group (C) Decreasing Pcv-aCO2/Ca-cvO2ratio (high at T0, declining at T6), Group (D) Persistently high PcvaCO2/ Ca-cvO2 ratio (high at T0 and T6).Results: During the 24-month period, 58 septic patients older than 18 years with a new episode were screened. Patients with advanced cirrhosis (n = 4), patients with severe chronic obstructive pulmonary disease (n = 8) and pregnant women (n = 4) were not included for analysis; additionally, two patients refused the procedure. The final sample was therefore 40 patients. Our recent study found that patients with persistently high Pcv-aCO2 gradient at T6 [8.64 ± 1.66] developed more organ dysfunction and have had a higher mortality rate (61.1%). This study showed that the persistently elevated Pcv-aCO2/Pa-vO2 ratio at time 6 was associated with a mortality rate of 73.7% of the patients. While decreasing of PcvaCO2/ Pa-vO2 ratio within the first 6 hours of resuscitation was associated with a survival rate of 90.5%. Conclusion: Data support the hypothesis that persistence of high PCO2 Gap and high Pcv-aCO2/ Pa-vO2 ratio during the early resuscitation of patients in sepsis is associated with significant higher multi-organ dysfunction and poor outcomes in critically-ill patients.

The validity of central venous to arterial carbon dioxide difference to predict adequate fluid management during living donor liver transplantation. A prospective observational study

BackgroundTo assess the validity of central and pulmonary veno-arterial CO2 gradients to predict fluid responsiveness and to guide fluid management during liver transplantation.MethodsIn adult recipients (ASA III to IV) scheduled for liver transplantation, intraoperative fluid management was guided by pulse pressure variations (PPV). PPV of ≥15% (Fluid Responding Status-FRS) indicated fluid resuscitation with 250 ml albumin 5% boluses repeated as required to restore PPV to < 15% (Fluid non-Responding Status-FnRS). Simultaneous blood samples from central venous and pulmonary artery catheters (PAC) were sent to calculate central venous to arterial CO2 gap [C(v-a) CO2 gap] and pulmonary venous to arterial CO2 gap [Pulm(p-a) CO2 gap]. CO and lactate were also measured.ResultsSixty seven data points were recorded (20 FRS and 47 FnRS). The discriminative ability of central and pulmonary CO2 gaps between the two states (FRS and FnRS) was poor with AUC of ROC of 0.698 and 0.570 respectively. Central CO2 gap was significantly higher in FRS than FnRS (P = 0.016), with no difference in the pulmonary CO2 gap between both states. The central and Pulmonary CO2 gaps are weakly correlated to PPV [r = 0.291, (P = 0.017) and r = 0.367, (P = 0.002) respectively]. There was no correlation between both CO2 gaps and both CO and lactate.ConclusionCentral and the Pulmonary CO2 gaps cannot be used as valid tools to predict fluid responsiveness or to guide fluid management during liver transplantation. CO2 gaps also do not correlate well with the changes in PPV or CO.Trial registrationClinicaltrials.gov Identifier: NCT03123172. Registered on 31-march-2017.

Empagliflozin Ameliorates Adverse Left Ventricular Remodeling in Nondiabetic Heart Failure by Enhancing Myocardial Energetics

BackgroundEmpagliflozin cardiac benefits in the EMPA-REG OUTCOME (Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) trial cannot be explained exclusively by its antihyperglycemic activity. ObjectivesThe hypothesis was that empagliflozin’s cardiac benefits are mediated by switching myocardial fuel metabolism away from glucose toward ketone bodies (KB), which improves myocardial energy production. MethodsHeart failure was induced in nondiabetic pigs (n = 14) by 2-h balloon occlusion of the proximal left anterior descending artery. Animals were randomized to empagliflozin or placebo for 2 months. Animals were evaluated with cardiac magnetic resonance imaging and 3-dimensional echocardiography. Myocardial metabolite consumption was analyzed by simultaneous blood sampling from coronary artery and coronary sinus. Myocardial samples were obtained for molecular evaluation. Nonmyocardial infarction animals served as comparison. ResultsDespite similar initial ischemic myocardial injury in both groups, the empagliflozin group showed amelioration of adverse remodeling at 2 months (lower left ventricular [LV] mass, reduced LV dilatation, less LV sphericity) versus the control group. LV systolic function (LV ejection fraction and echocardiography-derived strains) was improved, as was neurohormonal activation. Compared with nonmyocardial infarction, control animals increased myocardial glucose consumption mainly through anaerobic glycolysis while reducing utilization of free fatty acid (FFA) and branched-chain amino acid (BCAA). Empagliflozin-treated pigs did not consume glucose (reduction in myocardial glucose uptake, and glucose-related enzymes) but instead switched toward utilization of KB, FFA, and BCAA (increased myocardial uptake of these 3 metabolites, and enhanced expression/activity of the enzymes implicated in the metabolism of KB/FFA/BCAA). Empagliflozin increased myocardial ATP content and enhanced myocardial work efficiency. ConclusionsEmpagliflozin ameliorates adverse cardiac remodeling and heart failure in a nondiabetic porcine model. Empagliflozin switches myocardial fuel utilization away from glucose toward KB, FFA, and BCAA, thereby improving myocardial energetics, enhancing LV systolic function, and ameliorating adverse LV remodeling.

Simplified Criteria Using Pleural Fluid Cholesterol and Lactate Dehydrogenase to Distinguish between Exudative and Transudative Pleural Effusions

Background: An important part of the investigation of pleural effusion is the identification of markers that help separate exudate from transudate. Objectives: The purposes of this study were to compare the accuracy of published and new sets of criteria to distinguish between exudative and transudative pleural effusions, and to determine whether serum biochemical analysis is necessary. Methods: An externally validated cohort study was performed. Pleural effusions were determined to be transudative or exudative on the basis of an assessment of the medical record by two clinicians blinded to biochemical results. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and area under the receiver operating characteristic curve were determined for each proposed combination of criteria. Results: Pleural fluid analysis was available for 311 thoracenteses in the main cohort and for 112 thoracenteses in the validation cohort. The best sensitivity (97% [95% CI 94–99]) and negative likelihood ratio (0.04 [95% CI 0.02–0.08]) for identifying exudative effusions were observed with criteria combining pleural fluid lactate dehydrogenase greater than 0.6 the upper limit of normal serum lactate dehydrogenase and pleural fluid cholesterol greater than 1.04 mmol/L (40 mg/dL). The overall diagnostic accuracy was similar to Light’s criteria. Findings were similar in the validation cohort. Conclusions: Our proposed criteria using simultaneously pleural fluid lactate dehydrogenase and pleural fluid cholesterol can identify an exudate with a sensitivity and an overall diagnostic accuracy similar to Light’s criteria. It avoids simultaneous blood sampling, thus reducing patient discomfort and potential costs.

Absorbent Microbiopsy Sampling and RNA Extraction for Minimally Invasive, Simultaneous Blood and Skin Analysis.

Conventional skin biopsy limits the clinical research that involves cosmetically sensitive areas or pediatric applications due to its invasiveness. Here, we describe the protocol for usingan absorbent microneedle-based device, absorbent microbiopsy, for minimally invasive sampling of skin and blood mixture. Our goal is to help facilitate rapid progress in clinical research, the establishment of biomarkers for skin disease and reducing the risk for clinical research participants. In contrast to conventional skin biopsy techniques, the absorbent microbiopsy can be performed within seconds and does not require intensive training due to its simple design. In this report, we describe the use of absorbent microbiopsy, including loading and application, on avolunteer. Then, we show how to isolate RNA from the absorbed sample. Finally, we demonstrate the use of quantitative reverse transcription PCR (RT-qPCR) to quantify mRNA expression levels of both blood (CD3E and CD19) and skin (KRT14 and TYR). The methods that we describe utilize off the shelf kits and reagents. This protocol offers a minimally invasive approach for simultaneous sampling of skin and blood within the same absorbent microbiopsy matrix. We have found human ethics committees, clinicians and volunteers to be supportive of this approach to dermatological research.

Differentiating transudative and exudative pleural effusion by pleural fluid cholesterol

Background: Pleural effusion is one of the common condition encountered in day to day practise. Pleural effusions represent a very common diagnostic task to the physician. A correct diagnosis of the underlying disease is essential to rational management. Today there are a number of laboratory tests available to differentiate exudates and transudates which are considered cost effective to the patients, so this study was designed for the measurement of pleural fluid cholesterol to differentiate transudative and exudative pleural effusions (sensitivity-97.8%, specificity-100%) with the advantage that a contemporary blood sample is not required, thereby lowering cost of diagnostic procedure. Objectives: To study the diagnostic value of Pleural fluid Cholesterol in differentiating transudative and exudative pleural effusions. Methodology: This cross sectional descriptive study was conducted on patients of pleural effusion (n=60)age &gt;18 years patients with definitive clinical diagnosis and evidenced by radiological diagnosis of pleural effusion were taken as inclusion criteria. Results: The results showed majority of the patients were males (63.3%) and females (36.7%). According to lights criteria 46 patients were exudates and 14 patients were transudates and according to Pleural fluid Cholesterol criteria 45 patients were exudates and 15 patients were transudates with sensitivity of 97.8% and specificity of 100% and accuracy of 98.3%. Conclusion: The pleural fluid cholesterol criteria were found to be the most efficient criteria. Since this parameter involves the measurement of only pleural fluid values of cholesterol, it has following advantages-Economically it reduces number of biochemical tests and Simpler as there is no need to take simultaneous blood sample at the time of thoracocentesis.

Simultaneous collection of the portal and superior vena cava blood in conscious rats defined that intestinal epithelium is the major site of glucuronidation, but not sulfation and methylation, of quercetin.

Quercetin is a flavonoid with many physiological effects. Absorbed quercetin is rapidly conjugated in the intestinal epithelium and liver. Different positional isomers of quercetin conjugates have different physiological properties. However, the mechanisms of quercetin conjugation in the intestine are not fully clarified. We examined the regioselective quercetin conjugate formation in the intestine after oral administration of quercetin glycosides, by simultaneous sampling of blood from the portal vein and superior vena cava, and quantifying various positional isomers of quercetin glucuronides and sulfates in conscious rats. Concentrations of quercetin glucuronides were higher in blood from the portal vein than the superior vena cava, showing that glucuronidation mainly occurred in the intestine. Such differences were not observed for quercetin sulfates. Regioselectivity of the intestinal glucuronidation in quercetin hydroxyl groups were 7- >3'- >3- >4'-OH. Quercetin was mainly sulfated on 3'-OH at 30min, but on 4'-OH at 240min.

Quantitative pupillometry and neuron-specific enolase independently predict return of spontaneous circulation following cardiogenic out-of-hospital cardiac arrest: a prospective pilot study

This study aimed to identify neurological and pathophysiological factors that predicted return of spontaneous circulation (ROSC) among patients with out-of-hospital cardiac arrest (OHCA). This prospective 1-year observational study evaluated patients with cardiogenic OHCA who were admitted to a tertiary medical center, Nippon Medical School Hospital. Physiological and neurological examinations were performed at admission for quantitative infrared pupillometry (measured with NPi-200, NeurOptics, CA, USA), arterial blood gas, and blood chemistry. Simultaneous blood samples were also collected to determine levels of neuron-specific enolase (NSE), S-100b, phosphorylated neurofilament heavy subunit, and interleukin-6. In-hospital standard advanced cardiac life support was performed for 30 minutes.The ROSC (n = 26) and non-ROSC (n = 26) groups were compared, which a revealed significantly higher pupillary light reflex ratio, which was defined as the percent change between maximum pupil diameter before light stimuli and minimum pupil diameter after light stimuli, in the ROSC group (median: 1.3% [interquartile range (IQR): 0.0–2.0%] vs. non-ROSC: (median: 0%), (Cut-off: 0.63%). Furthermore, NSE provided the great sensitivity and specificity for predicting ROSC, with an area under the receiver operating characteristic curve of 0.86, which was created by plotting sensitivity and 1-specificity. Multivariable logistic regression analyses revealed that the independent predictors of ROSC were maximum pupillary diameter (odds ratio: 0.25, 95% confidence interval: 0.07–0.94, P = 0.04) and NSE at admission (odds ratio: 0.96, 95% confidence interval: 0.93–0.99, P = 0.04). Pupillary diameter was also significantly correlated with NSE concentrations (r = 0.31, P = 0.027). Conclusively, the strongest predictors of ROSC among patients with OHCA were accurate pupillary diameter and a neuronal biomarker, NSE. Quantitative pupillometry may help guide the decision to terminate resuscitation in emergency departments using a neuropathological rationale. Further large-scale studies are needed.

Somatic alterations in circulating cell-free DNA of oesophageal carcinoma patients during primary staging are indicative for post-surgical tumour recurrence

Oesophageal cancer (OC) has high mortality. This study aims at determining the feasibility of liquid biopsies for genomic profiling in early stage OC, comparing two different technologies for mutational analysis in circulating cell -free DNA (ccfDNA) and evaluating the clinical impact of these somatic alterations during primary staging. In 25 patients with locally advanced OC, endoscopic tumour biopsies and simultaneous blood samples were taken during primary staging. Genomic DNA from biopsies and ccfDNA were analysed for mutations using a 12 gene panel next-generation sequencing (NGS) assay as well as digital droplet PCR (ddPCR). Genetic data was correlated with patients’ outcome. In 21 of the tested biopsies (84%) at least one somatic mutation was detected by NGS. Mutations detected by NGS were detectable by ddPCR with similar allele frequencies. In three out of the 21 patients with proven mutations, the same mutations were also detectable in ccfDNA using NGS (14%). In contrast, ddPCR detected mutations in ccfDNA of five additional patients (8/21, 38%). Post-surgical outcome analysis was performed for those patients who had received complete tumour resection (n = 16). Five of them suffered from an early relapse within the first year after surgery, including four with detectable somatic mutations in ccfDNA during primary staging. Taken together, we showed a higher sensitivity for ddPCR compared to NGS in detecting mutated ccfDNA in OC. Detection of somatically altered ccfDNA during primary staging seems to be indicative for post-surgical tumour recurrence.

Abstract 4584: High-definition single-cell analysis of liquid and solid biopsies reveals heterogeneity of circulating tumor cells in metastatic colorectal cancer

Abstract Treatment of cancer patients is transitioning to personalized strategies using targeted drugs with the required companion biomarkers. Many current biomarkers are tissue-based, requiring a solid biopsy and limiting sampling frequency. Given this, there is significant interest in determining whether noninvasive, blood-based liquid biopsies, utilizing measurements of factors that exist in the blood such as circulating tumor cells (CTCs), reflect solid tumors and can serve as substitutes for solid tumor biopsies. Colorectal cancer with hepatic metastases (mCRC) is one of very few scenarios where metastatic patients routinely undergo surgical resection, providing an opportunity for accessible tissue and simultaneous blood sampling. We collected blood and tumor touch preparations from patients undergoing resection of CRC with the purpose to determine the correlation of solid biopsies and the liquid phase of solid tumors in the mCRC setting. Samples were processed using the previously described HD-SCA (High-Definition Single-Cell Analysis) workflow for high-resolution imaging and characterization of tumor cells at a single-cell level. Briefly, tumor cells were identified by presence of nuclear stain, pan-cytokeratin, and absence of CD45. The colon-specific marker CDX2 was included as a fourth color for further characterization. Subsets of cells were subjected to copy number variation (CNV) profiling. The comparison of pre- and post-surgery blood samples showed that the concentration of CTCs decreased significantly after surgery. The concentration was markedly higher in patients with synchronous disease undergoing simultaneous resection of the primary tumor, indicating that the presence of CTCs is related to tumor burden. Principal component analysis demonstrated that the CTCs were more similar to the metastatic cells than to the primary colon cells. While protein levels varied between the liquid and solid biopsy cell populations, morphologic parameters including, e.g., cell and nuclear area and roundness, were similar in the two. The intrapatient analysis showed heterogeneous CTC populations, in general with a small subset of cells bearing characteristics more similar to the solid tumor cells than the bulk of CTCs. The presence of subpopulations was further indicated by the CNV analysis, which showed that only a minority of CTCs had genomic rearrangements and that, in contrast to the solid biopsy cells, the rearranged cells were largely nonclonal. Based on the high-content HD-SCA data, the CTCs were further grouped into different subtypes. In conclusion, we introduce an approach for high-content comparison of liquid and solid biopsies at a single-cell level. We show that the concentration of CTCs is related to tumor burden, and present a subclassification of rare circulating cells in mCRC. Citation Format: Anna S. Gerdtsson, Jana-Aletta Thiele, Randolph Schaffer, Kelly Bethel, Steven Curley, Heinz-Josef Lenz, Diana L. Hanna, Jorge Nieva, Anand Kolatkar, Mariam Rodriguez Lee, James Hicks, Peter Kuhn. High-definition single-cell analysis of liquid and solid biopsies reveals heterogeneity of circulating tumor cells in metastatic colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4584.

Four Types of Pulse Oximeters Accurately Detect Hypoxia during Low Perfusion and Motion.

Pulse oximeter performance is degraded by motion artifacts and low perfusion. Manufacturers developed algorithms to improve instrument performance during these challenges. There have been no independent comparisons of these devices. We evaluated the performance of four pulse oximeters (Masimo Radical-7, USA; Nihon Kohden OxyPal Neo, Japan; Nellcor N-600, USA; and Philips Intellivue MP5, USA) in 10 healthy adult volunteers. Three motions were evaluated: tapping, pseudorandom, and volunteer-generated rubbing, adjusted to produce photoplethsmogram disturbance similar to arterial pulsation amplitude. During motion, inspired gases were adjusted to achieve stable target plateaus of arterial oxygen saturation (SaO2) at 75%, 88%, and 100%. Pulse oximeter readings were compared with simultaneous arterial blood samples to calculate bias (oxygen saturation measured by pulse oximetry [SpO2] - SaO2), mean, SD, 95% limits of agreement, and root mean square error. Receiver operating characteristic curves were determined to detect mild (SaO2 < 90%) and severe (SaO2 < 80%) hypoxemia. Pulse oximeter readings corresponding to 190 blood samples were analyzed. All oximeters detected hypoxia but motion and low perfusion degraded performance. Three of four oximeters (Masimo, Nellcor, and Philips) had root mean square error greater than 3% for SaO2 70 to 100% during any motion, compared to a root mean square error of 1.8% for the stationary control. A low perfusion index increased error. All oximeters detected hypoxemia during motion and low-perfusion conditions, but motion impaired performance at all ranges, with less accuracy at lower SaO2. Lower perfusion degraded performance in all but the Nihon Kohden instrument. We conclude that different types of pulse oximeters can be similarly effective in preserving sensitivity to clinically relevant hypoxia.

MA 15.03 Distribution of Circulating Tumor DNA in Lung Cancer: Analysis of Primary Lesion, Pulmonary Vein, Bone Marrow and Pripheral Blood

Circulating tumor DNA (ctDNA), extracted from plasma, is a non-invasive surrogate biomarker. However, the distribution of ctDNA in the body still remains to be elucidated. In this study, resected lung tumors, with simultaneous blood and bone marrow samples, were analyzed to elucidate the distribution of ctDNA.

Heparin Induces the Mobilization of Heart-Derived Multipotent Mesoangioblasts During Cardiac Surgery With Cardiopulmonary Bypass or Cardiac Catheterization.

We previously identified circulating mesoangioblasts (cMABs), a subset of mesenchymal stem cells that express cardiac mesodermal markers, in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). We also found that hepatocyte growth factor (HGF) is upregulated during cardiac surgery with CPB in humans, and induces MAB-like cell mobilization in rodents. These results strongly suggest that heparin induced MAB mobilization via HGF upregulation. Here, we tested this hypothesis in patients undergoing cardiac surgery or cardiac catheterization. We also examined whether human cMABs are derived from the heart.Methods and Results:Plasma HGF levels were determined by ELISA. Mononuclear cells isolated from blood samples were cultured on fibronectin-coated dishes, and outgrowing cMAB colonies were counted. We first confirmed that HGF upregulation and cMAB mobilization were observed before the start of CPB, excluding the possibility that CPB is the primary inducer of cMAB mobilization. We then examined patients undergoing cardiac catheterization and found that heparin significantly increased plasma HGF levels and the number of cMAB colonies in a dose-dependent manner. The results of simultaneous blood sampling from the aortic sinus, coronary sinus, and right atrium were consistent with the notion that human cMABs are derived from the heart. Human cMABs are mobilized by heparin injection during cardiac surgery or cardiac catheterization, presumably via HGF upregulation.

Distribution of circulating tumor DNA in lung cancer: analysis of the primary lung and bone marrow along with the pulmonary venous and peripheral blood.

Circulating tumor DNA (ctDNA), extracted from plasma, is a non-invasive surrogate biomarker. However, the distribution of ctDNA in the body still remains to be elucidated. In this study, resected lung tumors, with simultaneous blood and bone marrow samples, were analyzed to elucidate the distribution of ctDNA. Rib bone marrow, pulmonary venous blood (Pul.V) and peripheral blood (Peri.B) were obtained from 30 patients. The liquid samples were divided into cell pellets and supernatant by centrifugation; a total of 212 DNA samples were subjected to massively parallel sequencing. ctDNA was detected in 5 patients. Given that the frequency of mutations in the primary tumor was considered to be 100%, those in the other specimens were as follows; Pul.V plasma 20%, Peri.B plasma 11%, and the other samples 0%. Furthermore, ctDNA reflected the predominant mutations in the primary lesion. Clinically, the presence of ctDNA was associated with significantly poorer survival. These results suggest ctDNA “spill over” into an immediate outflow tract (Pul.V), and from there is disseminated to the entire body. Thus, it can be inferred that ctDNA reflects the cancer progression and could function as a prognostic marker.

Investigation of Regional Blood-Brain Barrier Integrity and Cerebral Efflux Transporter Function in Patients with Neuroepithelial Tumors by Means of [11C] Tariquidar Pet

At the human blood-brain barrier (BBB) high levels of efflux transporters, such as P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2), are expressed, which restrict the brain distribution of many drugs. The pharmacological treatment of brain tumors is often hampered by the impermeability of the BBB to anticancer drugs. It has been shown that the BBB may become disrupted in central necrotic parts of high-grade gliomas, leading to higher drug concentrations as compared to tumor-free brain tissue. In this study [11C]tariquidar, a drug-like radiotracer, which is subject to efflux transport by ABCB1 and ABCG2 at the human BBB, is used to study regional BBB integrity and cerebral efflux transporter function in patients with neuroepithelial tumors of the central nervous system (CNS). Seven patients diagnosed with a neuroepithelial tumor and elected for neurosurgery underwent a 60-min dynamic [11C]tariquidar brain PET scan and simultaneous arterial blood sampling. Four regions of interest (tumor, tumor rim, contralateral as well as ipsilateral tumor-free brain area) were delineated on MR-co-registered PET images. Logan graphical analysis was used to estimate the total distribution volume (VT) as a parameter of [11C]tariquidar distribution from blood to different brain regions. In all patients, brain distribution of [11C]tariquidar was very low, which was consistent with ABCB1/ABCG2-mediated efflux transport at the BBB. There were no significant differences in [11C]tariquidar VT values between tumor tissue and tumor-free tissue and between the central part of the tumor and the tumor rim. In 4 patients, VT values were lower in tumor tissue as compared to contralateral tumor-free brain tissue (-89% ± 78%, range: -22% to -200%). In 3 patients, VT values were higher in tumor tissue as compared with contralateral tumor-free brain tissue (+27% ± 14%, range: +13% to +40%). We found no significant differences in distribution of [11C]tariquidar to tumor tissue and tumor-free tissue, which argues against a major BBB disruption in these patients and suggests that anticancer drugs transported by ABCB1 and ABCG2, may not reach the tumor tissue in sufficiently high and therapeutically effective concentrations.

Relationships between body temperatures and inflammation indicators under physiological and pathophysiological conditions in pigs exposed to systemic lipopolysaccharide and dietary deoxynivalenol.

We studied the constancy of the relationship between rectal and intraabdominal temperature as well as their linkage to inflammatory markers (leucocyte counts, kynurenine-to-tryptophan ratio (Kyn-Trp ratio), tumour necrosis factor alpha (TNF-α) in healthy and in pigs exposed to lipopolysaccharide (LPS) and/or deoxynivalenol (DON). Barrows (n=44) were fed 4weeks either a DON-contaminated(4.59mg DON/kg feed)or a control (CON) diet andequipped with anintraabdominaltemperature logger and a multicatheter system (V.portaehepatis, V.lienalis, Vv.jugulares) facilitating infusion of 0.9% NaCl (CON) or LPS(7.5μg/kgBW) and simultaneous blood sampling. Body temperatures were measured and blood samples taken every 15min for leucocyte counts, TNF-α and Kyn-Trp ratio. Combination of diet and infusion created six groups: CON_CONjug .-CONpor. , CON_CONjug. -LPSpor. , CON_LPSjug. -CONpor. , DON_CONjug. -CONpor. , DON_CONjug. -LPSpor. , DON_LPSjug. -CONpor. . The relationship between both temperatures was not uniform for all conditions. Linear regression revealed that an intraabdominal increase per 1°C increase in rectal temperature was ~25% higher in all LPS-infused pigs compared to NaCl-infusion, albeit diet and site of LPS infusion modified the magnitude of this difference. Inflammatory markers were only strongly present under LPS influence and showed a significant relationship with body temperatures. For example, leucocyte counts in clinically inconspicuous animals were only significantly correlated to core temperature in DON-fed pigs, but in all LPS-infused groups, irrespective of diet and temperature method. In conclusion, the gradient between body core and rectal temperature is constant in clinically inconspicuous pigs, but not under various pathophysiological conditions. In the latter, measurement of inflammatory markers seems to be a useful completion.