Distribution of Cardiac Stem Cells in the Human Heart

Introduction. The existence of human cardiac stem cells (hCSC) and their regenerative capacity are not fully defined. The aim of this study was to identify and analyse the distribution of hCSCs by flow cytometry (FCM). Methods. Tissue samples from the left ventricle (LV) and the appendages of the right atrium (RA) and left atrium (LA) were taken during cardiac surgery. Mononuclear cells (MNCs) were isolated, labelled for the stem-cell-marker c-kit and hematopoietic-lineage markers and analysed by FCM. Results. HCSCs could be isolated from the RA, LA, and LV without significant quantitative difference between both atria (A) (RA 4.80 ± 1.76% versus LA 4.99 ± 1.69% of isolated MNCs, P = 0.922). The number of hCSCs was significantly higher in both atria compared to the left ventricle (A 4.90 ± 1.29% versus LV 0.62 ± 0.14% of isolated MNCs, P = 0.035). Conclusion. The atria contain a higher concentration of hCSC than the left ventricle. HCSCs located in the atria could serve as an endogenous source for heart regeneration

Simultaneous identification of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and Trichomonas vaginalis ‒ multicenter evaluation of the Alinity m STI assay

Abstract Objectives Accurate and rapid diagnosis of sexually transmitted infections (STIs) is essential for timely administration of appropriate treatment and reducing the spread of the disease. We examined the performance of the new Alinity m STI assay, a qualitative real-time multiplex PCR test for simultaneous identification of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), and Trichomonas vaginalis (TV) run on the fully automated Alinity m platform. Methods This international, multicenter study evaluated the accuracy, reproducibility, and clinical performance of the Alinity m STI assay compared to commonly used STI assays in a large series of patient samples encountered in clinical practice. Results The Alinity m STI assay identified accurately and precisely single and mixed pathogens from an analytical panel of specimens. The Alinity m STI assay demonstrated high overall agreement rates with comparator STI assays (99.6% for CT [n=2,127], 99.2% for NG [n=2,160], 97.1% for MG [n=491], and 99.4% for TV [n=313]). Conclusions The newly developed Alinity m STI assay accurately detects the 4 sexually transmitted target pathogens in various collection devices across clinically relevant specimen types, regardless of single or mixed infection status

Improved molecular laboratory productivity by consolidation of testing on the new random-access analyzer Alinity m

Abstract Objectives Automated molecular analyzers have accelerated diagnosis, allowing earlier intervention and better patient follow-up. A recently developed completely automated molecular analyzer, Alinity™ m (Abbott), offers consolidated, continuous, and random-access testing that may improve molecular laboratory workflow. Methods An international, multicenter study compared laboratory workflow metrics across various routine analyzers and Alinity m utilizing assays for human immunodeficiency virus type 1 (HIV-1), hepatitis C virus (HCV), hepatitis B virus (HBV), high-risk human papillomavirus (HR HPV), and sexually transmitted infection (STI) (Chlamydia trachomatis [CT]/Neisseria gonorrhoeae [NG]/Trichomonas vaginalis [TV]/Mycoplasma genitalium [MG]). Three turnaround times (TATs) were assessed: total TAT (sample arrival to result), sample onboard TAT (sample loading and test starting to result), and processing TAT (sample aspiration to result). Results Total TAT was reduced from days with routine analyzers to hours with Alinity m, independent of requested assays. Sample onboard TATs for standard workflow using routine analyzers ranged from 7 to 32.5 h compared to 2.75–6 h for Alinity m. The mean sample onboard TAT for STAT samples on Alinity m was 2.36 h (±0.19 h). Processing TATs for Alinity m were independent of the combination of assays, with 100% of results reported within 117 min. Conclusions The consolidated, continuous, random-access workflow of Alinity m reduces TATs across various assays and is expected to improve both laboratory operational efficiency and patient care

Improving compliance to colorectal cancer screening using blood and stool based tests in patients refusing screening colonoscopy in Germany

Background Despite strong recommendations for colorectal cancer (CRC) screening, participation rates are low. Understanding factors that affect screening choices is essential to developing future screening strategies. Therefore, this study assessed patient willingness to use non-invasive stool or blood based screening tests after refusing colonoscopy. Methods Participants were recruited during regular consultations. Demographic, health, psychological and socioeconomic factors were recorded. All subjects were advised to undergo screening by colonoscopy. Subjects who refused colonoscopy were offered a choice of non-invasive tests. Subjects who selected stool testing received a collection kit and instructions; subjects who selected plasma testing had a blood draw during the office visit. Stool samples were tested with the Hb/Hp Complex Elisa test, and blood samples were tested with the Epi proColon® 2.0 test. Patients who were positive for either were advised to have a diagnostic colonoscopy. Results 63 of 172 subjects were compliant to screening colonoscopy (37%). 106 of the 109 subjects who refused colonoscopy accepted an alternative non-invasive method (97%). 90 selected the Septin9 blood test (83%), 16 selected a stool test (15%) and 3 refused any test (3%). Reasons for blood test preference included convenience of an office draw, overall convenience and less time consuming procedure. Conclusions 97% of subjects refusing colonoscopy accepted a non-invasive screening test of which 83% chose the Septin9 blood test. The observation that participation can be increased by offering non-invasive tests, and that a blood test is the preferred option should be validated in a prospective trial in the screening setting

Multicenter clinical comparative evaluation of Alinity m HIV-1 assay performance.

Abstract Background Accurate, rapid detection of HIV-1 RNA is critical for early diagnosis, treatment decision making, and long-term management of HIV-1 infection. Objective We evaluated the diagnostic performance of the Alinity m HIV-1 assay, which uses a dual target/dual probe design against highly conserved target regions of the HIV-1 genome and is run on the fully automated Alinity m platform. Study design This was an international, multisite study that compared the diagnostic performance of the Alinity m HIV-1 assay to four commercially available HIV-1 assays routinely used in nine independent clinical laboratories. Alinity m HIV-1 assay precision, detectability, and reproducibility was compared across four study sites. Results The Alinity m HIV-1 assay produced comparable results to currently available HIV-1 assays (correlation coefficient >0.995), with an overall bias of -0.1 to 0.10 Log10 copies/mL. The Alinity m HIV-1 assay and its predecessor m2000 HIV-1 assay demonstrated comparable detection of 16 different HIV-1 subtypes (R2 = 0.956). A high level of agreement (>88 %) between all HIV-1 assays was seen near clinical decision points of 1.7 Log10 copies/mL (50 copies/mL) and 2.0 Log10 copies/mL (200 copies/mL). Alinity m HIV-1 assay precision was 0.08 and 0.21 Log10 copies/mL at VLs of 1000 and 50 copies/mL, respectively, with a high level of detectability (≥97 % hit rate) and reproducibility across sites. Conclusions The Alinity m HIV-1 assay provides comparable diagnostic accuracy to current HIV-1 assays, and when run on the Alinity m system, has the capacity to shorten the time between diagnosis and treatment

Effects of autologous bone marrow stem cell transplantation on beta-adrenoceptor density and electrical activation pattern in a rabbit model of non-ischemic heart failure

BACKGROUND: Since only little is known on stem cell therapy in non-ischemic heart failure we wanted to know whether a long-term improvement of cardiac function in non-ischemic heart failure can be achieved by stem cell transplantation. METHODS: White male New Zealand rabbits were treated with doxorubicine (3 mg/kg/week; 6 weeks) to induce dilative non-ischemic cardiomyopathy. Thereafter, we obtained autologous bone marrow stem cells (BMSC) and injected 1.5–2.0 Mio cells in 1 ml medium by infiltrating the myocardium via a left anterolateral thoracotomy in comparison to sham-operated rabbits. 4 weeks later intracardiac contractility was determined in-vivo using a Millar catheter. Thereafter, the heart was excised and processed for radioligand binding assays to detect β(1)- and β(2)-adrenoceptor density. In addition, catecholamine plasma levels were determined via HPLC. In a subgroup we investigated cardiac electrophysiology by use of 256 channel mapping. RESULTS: In doxorubicine-treated animals β-adrenoceptor density was significantly down-regulated in left ventricle and septum, but not in right ventricle, thereby indicating a typical left ventricular heart failure. Sham-operated rabbits exhibited the same down-regulation. In contrast, BMSC transplantation led to significantly less β-adrenoceptor down-regulation in septum and left ventricle. Cardiac contractility was significantly decreased in heart failure and sham-operated rabbits, but was significantly higher in BMSC-transplanted hearts. Norepinephrine and epinephrine plasma levels were enhanced in heart failure and sham-operated animals, while these were not different from normal in BMSC-transplanted animals. Electrophysiological mapping revealed unaltered electrophysiology and did not show signs of arrhythmogeneity. CONCLUSION: BMSC transplantation improves sympathoadrenal dysregualtion in non-ischemic heart failure

The Range of Uncertainty: a Tool for Efficiently Addressing Result Variability Around Clinical Decision Points for Hepatitis C Response-Guided Therapy

Despite efforts to standardize molecular diagnostic tests, performance differences are not rare. Laboratories are challenged in situations where treatment rules have been established using a reference assay that is different from the assays being used in daily practice. Assessing the viral load status of patients with chronic hepatitis C under modern triple therapy is a recognized example. We demonstrate the use of the range of uncertainty as an easy and efficient tool that can provide information on the certainty of a test result's interpretation in the context of making hepatitis C virus treatment decisions

Flow Cytometric Evaluation of T Cell Activation Markers after Cardiopulmonary Bypass

Background. Cardiopulmonary bypass surgery (CPBS) is associated with an increased risk for infections or with subsequent organ dysfunction. As T cell activation is a central mechanism during inflammatory processes, we developed an assay to evaluate T cell activation pathways in patients undergoing CPBS. Methods. Blood was obtained from eleven patients undergoing CPBS preoperatively, on postoperative day (POD)-3, and on POD-7 and was stimulated with different concentrations of Concanavalin A (ConA). Cyclosporine and sirolimus, inhibiting different pathways of the T cell cycle, were added to blood ex vivo. Expression of T cell activation markers CD25 and CD95 was analyzed by flow cytometry. Results. In untreated blood, expression of CD25 and CD95 significantly increased with higher ConA concentrations (P<0.05) and decreased for all ConA concentrations for both antigens over the study time (P<0.05). Independently from the ConA concentration, inhibition of CD25 and CD95 expression was highest preoperatively for sirolimus and on POD-3 for cyclosporine. At all time points, inhibition of CD25 and CD95 expression was significantly higher after cyclosporine compared to sirolimus treatment (P<0.001). Conclusion. Our results showed that different pathways of T cell activation are impaired after CPBS. Such knowledge may offer the opportunity to identify patients at risk for postoperative complications

Flow Cytometric Evaluation of T Cell Activation Markers after Cardiopulmonary Bypass

Background. Cardiopulmonary bypass surgery (CPBS) is associated with an increased risk for infections or with subsequent organ dysfunction. As T cell activation is a central mechanism during inflammatory processes, we developed an assay to evaluate T cell activation pathways in patients undergoing CPBS. Methods. Blood was obtained from eleven patients undergoing CPBS preoperatively, on postoperative day (POD)-3, and on POD-7 and was stimulated with different concentrations of Concanavalin A (ConA). Cyclosporine and sirolimus, inhibiting different pathways of the T cell cycle, were added to blood ex vivo. Expression of T cell activation markers CD25 and CD95 was analyzed by flow cytometry. Results. In untreated blood, expression of CD25 and CD95 significantly increased with higher ConA concentrations ( &lt; 0.05) and decreased for all ConA concentrations for both antigens over the study time ( &lt; 0.05). Independently from the ConA concentration, inhibition of CD25 and CD95 expression was highest preoperatively for sirolimus and on POD-3 for cyclosporine. At all time points, inhibition of CD25 and CD95 expression was significantly higher after cyclosporine compared to sirolimus treatment ( &lt; 0.001). Conclusion. Our results showed that different pathways of T cell activation are impaired after CPBS. Such knowledge may offer the opportunity to identify patients at risk for postoperative complications