Protocol and standard operating procedures for common use in a worldwide multicenter study on reference values

The reference intervals (RIs) given in laboratory reports have an important role in aiding clinicians in interpreting test results in reference to values of healthy populations. In this report, we present a proposed protocol and standard operating procedures (SOPs) for common use in conducting multicenter RI studies on a national or international scale. The protocols and consensus on their contents were refined through discussions in recent C-RIDL meetings. The protocol describes in detail (1) the scheme and organization of the study, (2) the target population, inclusion/exclusion criteria, ethnicity, and sample size, (3) health status questionnaire, (4) target analytes, (5) blood collection, (6) sample processing and storage, (7) assays, (8) cross-check testing, (9) ethics, (10) data analyses, and (11) reporting of results. In addition, the protocol proposes the common measurement of a panel of sera when no standard materials exist for harmonization of test results. It also describes the requirements of the central laboratory, including the method of cross-check testing between the central laboratory of each country and local laboratories. This protocol and the SOPs remain largely exploratory and may require a reevaluation from the practical point of view after their implementation in the ongoing worldwide study. The paper is mainly intended to be a basis for discussion in the scientific community.Japan Society for the Promotion of Science (24256003

Generation of human antibody fragments against Streptococcus mutans using a phage display chain shuffling approach

BACKGROUND: Common oral diseases and dental caries can be prevented effectively by passive immunization. In humans, passive immunotherapy may require the use of humanized or human antibodies to prevent adverse immune responses against murine epitopes. Therefore we generated human single chain and diabody antibody derivatives based on the binding characteristics of the murine monoclonal antibody Guy's 13. The murine form of this antibody has been used successfully to prevent Streptococcus mutans colonization and the development of dental caries in non-human primates, and to prevent bacterial colonization in human clinical trials. RESULTS: The antibody derivatives were generated using a chain-shuffling approach based on human antibody variable gene phage-display libraries. Like the parent antibody, these derivatives bound specifically to SAI/II, the surface adhesin of the oral pathogen S. mutans. CONCLUSIONS: Humanization of murine antibodies can be easily achieved using phage display libraries. The human antibody fragments bind the antigen as well as the causative agent of dental caries. In addition the human diabody derivative is capable of aggregating S. mutans in vitro, making it a useful candidate passive immunotherapeutic agent for oral diseases

Heart-Type Fatty Acid-Binding Protein Predicts Long-Term Mortality and Re-Infarction in Consecutive Patients With Suspected Acute Coronary Syndrome Who Are Troponin-Negative

ObjectivesThe purpose of this study was to establish the prognostic value of measuring heart fatty acid-binding protein (H-FABP) in patients with suspected acute coronary syndrome (ACS) (in particular, low- to intermediate-risk patients), in addition to troponin measured with the latest third-generation troponin assay.BackgroundWe have previously shown that H-FABP is a useful prognostic marker in patients with proven ACS.MethodsPatients (n = 1,080) consecutively admitted to the hospital with suspected ACS were recruited over 46 weeks. Siemens Advia Ultra-TnI (Siemens Healthcare Diagnostics, Newbury, United Kingdom) and Randox Evidence H-FABP (Randox Laboratories, Ltd., Co., Antrim, United Kingdom) were analyzed on samples collected 12 to 24 h from symptom onset. After exclusion of patients with ST-segment elevation and new left bundle branch block, 955 patients were included in the analysis.ResultsThe primary outcome measure of death or readmission with myocardial infarction after a minimum follow-up period of 12 months (median 18 months) occurred in 96 of 955 patients (10.1%). The H-FABP concentration was an independent predictor of death or myocardial infarction, after multivariate adjustment. Patients with H-FABP concentrations >6.48 μg/l had significantly increased risk of adverse events (adjusted hazard ratio: 2.62, 95% confidence interval: 1.30 to 5.28, p = 0.007). Among troponin-negative patients (which constituted 79.2% of the cohort), the aforementioned cutoff of 6.48 μg/l identified patients at very high risk for adverse outcomes independent of patient age and serum creatinine.ConclusionsWe have demonstrated that the prognostic value of elevated H-FABP is additive to troponin in low- and intermediate-risk patients with suspected ACS. Other studies suggest that our observations reflect the value of H-FABP as a marker of myocardial ischemia, even in the absence of frank necrosis

Lipogenesis by Isolated Human Apocrine Sweat Glands: Testosterone Has no Effect During Long-Term Organ Maintenance

Lipid synthesis by freshly isolated human apocrine glands has been measured by the incorporation of [U-14C] acetate. Incorporation is linear over 6h at 1010 ± 282 pmol/mg wet weight/h (n = 11; mean ± sem). The lipid classes, as percentages of the total lipid synthesized, were found by TLC to be cholesterol 12.3 ± 2.0, mono-glycerides 7.5 ± 1.5, 1,2 di-glycerides 3.0 ± 0.9, 1,3 di-glycerides 3.5 ± 0.5, tri-glycerides 28.4 ± 1.8, free fatty acids 2.0 ± 0.4, lysolecithin 15.4 ± 3.9, sphingomyelin 9.9 ± 4.3, phosphatidyl-choline 8.4 ± 0.4, phosphatidyl-ethanolamine -inositol and -serine 1.8 ± 0.1, phosphatidic acid and cardiolipin 3.3 ± 0.5, and unidentified 3.3 ± 0.5 (mean ± sem, n = 5); Glands were maintained on permeable supports. After 10 d maintenance, electron microscopy showed that the cellular architecture had been preserved, that the ATP contents were the same as in freshly isolated glands, and that [U-14]C] acetate incorporation was not significantly altered at 851 ± 237 pmol/mg/h (n = 18). The addition of 3μM testosterone had no effect on acetate incorporation at 844 ± 231 pmol/mg/h (n = 18). The lipid classes and their proportions were similar to the values for fresh glands after 10 d maintenance both with and without testosterone

Discovering the sluggishness of triathlon running - using the attractor method to quantify the impact of the bike-run transition

Running in a triathlon, a so-called brick run, is uniquely influenced by accumulated load from its preceding disciplines. Crucially, however, and irrespective of race type, the demands of a triathlon always exceed the sum of its parts. Triathletes of all levels commonly report subjectively perceived incoordination within the initial stages of the cycle run transition (T2). Although minimizing it, and its influence on running kinematics, can positively impact running and overall triathlon performance, the mechanisms behind the T2 effect remain unclear. In the present study, we assessed the influence of the pre-load exercise mode focusing on the biomechanical perspective. To analyze inertial sensor-based raw data from both legs, the so-called Attractor Method was applied. The latter represents a sensitive approach, allowing to quantify subtle changes of cyclic motions to uncover the transient effect, a potentially detrimental transient phase at the beginning of a run. The purpose was to analyze the impact of a pre-load on the biomechanics of a brick run during a simulated Olympic Distance triathlon (without the swimming section). Therefore, we assessed the influence of pre-load exercise mode on running pattern (δM) and precision (δD), and on the length of the transient effect (tT) within a 10 km field-based run in 22 well-trained triathletes. We found that δD, but not δM, differed significantly between an isolated run (IRun) and when it was preceded by a 40 km cycle (TRun) or an energetically matched run (RRun). The average distance ran until overcoming the transient phase (tT) was 679 m for TRun, 450 m for RRun, and 29 4 m for IRun. The results demonstrated that especially the first kilometer of a triathlon run is prone to an uncoordinated running sensation, which is also commonly reported by athletes. That is, i) the T2 effect appeared more linked to variability in running style than to running style per se ii) run tT distance was influenced by preceding exercise load mode, being greater for a TRun than for the RRun condition, and iii) the Attractor Method seemed to be a potentially promising method of sensitively monitoring T2 adaptation under ecologically valid conditions