A Multicenter Study to Evaluate Harmonization of Assays for C-Terminal Telopeptides of Type I Collagen (ß-CTX): A Report from the IFCC-IOF Committee for Bone Metabolism (C-BM)

Abstract Background Biochemical bone turnover markers are useful tools to assess bone remodeling. C-terminal telopeptide of type I collagen (ß-CTX) has been recommended as a reference marker for bone resorption in research studies. Methods We describe the results of a multicenter study for routine clinical laboratory assays for ß-CTX in serum and plasma. Four centers (Athens GR, Copenhagen DK, Liege BE and Sheffield UK) collected serum and plasma (EDTA) samples from 796 patients presenting to osteoporosis clinics. Specimens were analyzed in duplicate with each of the available routine clinical laboratory methods according to the manufacturers’ instructions. Passing-Bablok regressions, Bland–Altman plots, V-shape evaluation method, and Concordance correlation coefficient for ß-CTX values between serum and plasma specimens and between methods were used to determine the agreement between results. A generalized linear model was employed to identify possible variables that affected the relationship between the methods. Two pools of serum were finally prepared and sent to the four centers to be measured in 5-plicates on 5 consecutive days with the different methods. Results We identified significant variations between methods and between centers although comparison results were generally more consistent in plasma compared to serum. We developed univariate linear regression equations to predict Roche Elecsys®, IDS-iSYS, or IDS ELISA ß-CTX results from any other assay and a multivariable model including the site of analysis, the age, and weight of the patient. The coefficients of determination (R2) increased from approximately 0.80 in the univariate model to approximately 0.90 in the multivariable one, with the site of analysis being the major contributing factor. Results observed on the pools also suggest that long-term storage could explain the difference observed with the different methods on serum. Conclusion Our results show large within- and between-assay variation for ß-CTX measurement, particularly in serum. Stability of the analyte could be one of the explanations. More studies should be undertaken to overcome this problem. Until harmonization is achieved, we recommend measuring ß-CTX by the same assay on EDTA plasma, especially for research purposes in large pharmacological trials where samples can be stored for long periods before they are assayed.

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A multicenter study to evaluate harmonization of assays for N-terminal propeptide of type I procollagen (PINP): a report from the IFCC-IOF Joint Committee for Bone Metabolism

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2019-0174 ◽

2019 ◽

Vol 57 (10) ◽

pp. 1546-1555 ◽

Cited By ~ 4

Author(s):

Etienne Cavalier ◽

Richard Eastell ◽

Niklas Rye Jørgensen ◽

Konstantinos Makris ◽

Symeon Tournis ◽

...

Keyword(s):

Multicenter Study ◽

Evaluation Method ◽

Clinical Laboratory ◽

Cellular Level ◽

Type I ◽

Type I Procollagen ◽

Edta Plasma ◽

Turnover Markers ◽

Routine Clinical Laboratory ◽

The Relationship

Abstract Background Biochemical bone turnover markers (BTM) are useful tools to assess bone remodeling at the cellular level. N-terminal propeptide of type I procollagen (PINP) has been recommended as a reference marker for bone formation in research studies. Methods We describe the results of a multicenter study for routine clinical laboratory assays for PINP in serum and plasma. Four centers (Athens, Greece [GR], Copenhagen, Denmark [DK], Liege, Belgium [BE] and Sheffield, United Kingdom [UK]) collected serum and plasma (EDTA) samples from 796 patients presenting to osteoporosis clinics. Specimens were analyzed in duplicate with each of the available routine clinical laboratory methods according to the manufacturers’ instructions. Passing-Bablok regressions, Bland-Altman plots, V-shape evaluation method and the concordance correlation coefficient for PINP values between serum and plasma specimens and between methods were used to determine the agreement between results. A generalized linear model was employed to identify possible variables that affected the relationship between the methods. Results We showed that both EDTA plasma and serum were suitable for PINP determination. We observed a significant proportional bias between Orion radioimmunoassay and the automated methods for PINP (Roche Cobas and IDS iSYS), which both gave very similar results. The multivariate model did not improve the excellent correlation that was observed between the methods. Conclusions Harmonization of PINP assays is possible by applying a correction factor or correctly assigning the values of the calibrators. This work will benefit from further collaboration between assays manufacturers and clinical laboratory professionals.

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Contractile properties of EDL and soleus muscles of myostatin-deficient mice

Journal of Applied Physiology ◽

10.1152/japplphysiol.00126.2006 ◽

2006 ◽

Vol 101 (3) ◽

pp. 898-905 ◽

Cited By ~ 95

Author(s):

Christopher L. Mendias ◽

James E. Marcin ◽

Daniel R. Calerdon ◽

John A. Faulkner

Keyword(s):

Type I Collagen ◽

Contractile Properties ◽

Negative Regulator ◽

Type I ◽

Lengthening Contractions ◽

Tetanic Force ◽

The Difference ◽

The Impact ◽

Deficient Mice

Myostatin is a negative regulator of muscle mass. The impact of myostatin deficiency on the contractile properties of healthy muscles has not been determined. We hypothesized that myostatin deficiency would increase the maximum tetanic force (Po), but decrease the specific Po(sPo) of muscles and increase the susceptibility to contraction-induced injury. The in vitro contractile properties of extensor digitorum longus (EDL) and soleus muscles from wild-type ( MSTN+/+), heterozygous-null ( MSTN+/−), and homozygous-null ( MSTN−/−) adult male mice were determined. For EDL muscles, the Poof both MSTN+/−and MSTN−/−mice were greater than the Poof MSTN+/+mice. For soleus muscles, the Poof MSTN−/−mice was greater than that of MSTN+/+mice. The sPoof EDL muscles of MSTN−/−mice was less than that of MSTN+/+mice. For soleus muscles, however, no difference in sPowas observed. Following two lengthening contractions, EDL muscles from MSTN−/−mice had a greater force deficit than that of MSTN+/+or MSTN+/−mice, whereas no differences were observed for the force deficits of soleus muscles. Myostatin-deficient EDL muscles had less hydroxyproline, and myostatin directly increased type I collagen mRNA expression and protein content. The difference in the response of EDL and soleus muscles to myostatin may arise from differences in the levels of a myostatin receptor, activin type IIB. Compared with the soleus, the amount of activin type IIB receptor was approximately twofold greater in EDL muscles. The results support a significant role for myostatin not only in the mass of muscles but also in the contractility and the composition of the extracellular matrix of muscles.

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Homozygous Type I Protein C Deficiency in Two Unrelated Families Exhibiting Thrombophilia Related to Ala136→Pro or Arg286→His Mutations

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648908 ◽

1994 ◽

Vol 72 (04) ◽

pp. 526-533 ◽

Cited By ~ 4

Author(s):

G L Long ◽

J A Tomczak ◽

I R Rainville ◽

M Dreyfus ◽

W Schramm ◽

...

Keyword(s):

Genetic Analysis ◽

Protein C ◽

Clinical Laboratory ◽

Polymerase Chain Reaction Amplification ◽

Type I ◽

Protein C Deficiency ◽

Restriction Endonuclease Site ◽

Direct Dna Sequencing ◽

Serine Protease Domain ◽

The Difference

SummarySeparate single nucleotide mutations have been identified in two unrelated homozygous type I protein C deficient individuals suffering from thrombophilia. Each mutation, initially established by direct DNA sequencing of polymerase chain reaction amplification products, results in an amino acid substitution. The first mutation (PCClamart) results in an Ala136 to Pro substitution in the protein’s second epidermal growth factor-like domain. The second mutation (PCMtinchen) results in an Arg286 to His substitution in the serine protease domain. Comparison of the location of these two mutations and the relative conservation of the two regions in homologous vitamin K-dependent plasma proteins is consistent with the difference in severity of protein C deficiency and disease in the two individuals. Both mutations result in the abolition of a naturally occurring restriction endonuclease site, thereby allowing independent confirmation of the mutations and rapid and unambiguous genetic analysis of protein C deficiency in family members. In both families, the genetic analysis has proven useful in cases where an assignment of the protein C status based upon clinical laboratory measurements was either ambiguous or incorrect.

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AFM Imaging of Water, Cells and Tissues

MRS Proceedings ◽

10.1557/proc-874-l4.1 ◽

2005 ◽

Vol 874 ◽

Author(s):

Xiaodong Li

Keyword(s):

Type I Collagen ◽

Calibration Method ◽

Phase Imaging ◽

Type I ◽

Contact Mode ◽

Tapping Mode ◽

Afm Imaging ◽

The Difference ◽

Afm Cantilever ◽

Pit Cell

AbstractThis paper presents the results of several AFM case studies of water, tumor cells, pit cells, and type-I collagen samples. The AFM imaging procedures, surface structural characterization capabilities such as contact mode, tapping mode, and friction mode are discussed. The difference in surface morphology between the pit cell submerged in liquid and the cell in air was observed. The AFM tapping mode phase imaging technique was used to study the crosslinks in the type-I collagen. The calibration method for accurately measuring the AFM cantilever spring constant with the help of a nanoindenter is also presented.

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Correction to: A Multicenter Study to Evaluate Harmonization of Assays for C-Terminal Telopeptides of Type I Collagen (ß-CTX): A Report from the IFCC-IOF Committee for Bone Metabolism (C-BM)

Calcified Tissue International ◽

10.1007/s00223-021-00839-y ◽

2021 ◽

Author(s):

E. Cavalier ◽

◽

R. Eastell ◽

N. R. Jørgensen ◽

K. Makris ◽

...

Keyword(s):

Bone Metabolism ◽

Multicenter Study ◽

Type I Collagen ◽

Type I

A correction to this paper has been published: https://doi.org/10.1007/s00223-021-00839-y

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IBD1: The metrics and evaluation method for DNN processor benchmark while doing Inference task

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-202552 ◽

2021 ◽

pp. 1-13

Author(s):

Wei Min Zhang ◽

Long Zhang ◽

Zheyu Zhang ◽

Mingjun Sun

Keyword(s):

Deep Learning ◽

Evaluation System ◽

Evaluation Method ◽

Hardware Acceleration ◽

Performance Comparison ◽

Current Status ◽

Input Size ◽

Comparison Results ◽

The Difference ◽

The Many

With the many varieties of AI hardware prevailing on the market, it is often hard to decide which one is the most suitable to use but not only with the best performance. As there is an industry-wide trend demand for deep learning deployment, the inference benchmark for the effectiveness of DNN processor becomes important and is of great help to select and optimize AI hardware. To systematically benchmark deep learning deployment platforms, and give more objective and useful metrics comparison. In this paper, an end to end benchmark evaluation system was brought up called IBD, it combined 4 steps include three components with 6 metrics. The performance comparison results are obtained from the chipsets from Qualcomm, HiSilicon, and NVIDIA, which can provide hardware acceleration for AI inference. To comprehensively reflect the current status of the DNN processor deploying performance, we chose six devices from three kinds of deployment scenarios which are cloud, desktop and mobile, ten models from three different kinds of applications with diverse characteristics are selected, and all these models are trained from three major training frameworks. Several important observations were made by using our methodologies. Experimental results showed that workload diversity should focus on the difference came from training frameworks, inference frameworks with specific processors, input size and precision (floating and quantized).

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The difference between residual monomer dentin bonding HEMA and UDMA with acetone and ethanol solvent after binding to type I collagen

Dental Journal (Majalah Kedokteran Gigi) ◽

10.20473/j.djmkg.v51.i4.p169-172 ◽

2018 ◽

Vol 51 (4) ◽

pp. 169

Author(s):

N. Normayanti ◽

Adioro Soetojo ◽

Nirawati Pribadi

Keyword(s):

High Performance ◽

Type I Collagen ◽

Composite Resin ◽

Tooth Surface ◽

Type I ◽

Residual Monomer ◽

Dentin Bonding ◽

Post Operative Pain ◽

The Difference ◽

Caries Lesions

Background: In caries and non-caries lesions involving dentine, it is necessary to provide dentine-bonding material to help improve retention between the composite resin and the tooth surface. Composite resin attachment to dentine is influenced by bonding polymerization reactions. In several studies, researchers found that polymerized monomers will experience volume shrinkage because not all will fully polymerize but, rather, become residual monomers that can cause post-operative pain. Purpose: This study aimed to identify the difference in the amount of residual monomers between HEMA- and UDMA-based dentin bonding materials with acetone and ethanol solvents after binding to type I collagen. Methods: Four groups featured in this study: HEMA with acetone solvent and type I collagen , HEMA with ethanol solvent and type I collagen , UDMA with acetone solvent and type I collagen and UDMA with ethanol solvent and type I collagen . All groups were checked by high performance liquid chromatography (HPLC) to quantify the remaining amount of monomers. Results: The percentage of residual monomers of dentine bonding HEMA with acetone solvent and type I collagen was 10.69%, HEMA with ethanol solvent and type I collagen was 13.93%, UDMA with acetone solvent and type I collagen was 2.89% and UDMA with ethanol solvent and type I collagen was 7.48%. Conclusion: HEMA with ethanol solvent has the highest number of residual monomers, while UDMA with acetone solvent has the lowest.

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Collagen fibrillogenesis in vitro: interaction of types I and V collagen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142670 ◽

1986 ◽

Vol 44 ◽

pp. 210-211

Author(s):

Arthur J. Wasserman ◽

Kathy C. Kloos ◽

David E. Birk

Keyword(s):

Type I Collagen ◽

Corneal Stroma ◽

Minor Component ◽

Homogeneous Distribution ◽

Type I ◽

Type V Collagen ◽

Fibril Morphology ◽

Type V ◽

In Vitro Interaction

Type I collagen is the predominant collagen in the cornea with type V collagen being a quantitatively minor component. However, the content of type V collagen (10-20%) in the cornea is high when compared to other tissues containing predominantly type I collagen. The corneal stroma has a homogeneous distribution of these two collagens, however, immunochemical localization of type V collagen requires the disruption of type I collagen structure. This indicates that these collagens may be arranged as heterpolymeric fibrils. This arrangement may be responsible for the control of fibril diameter necessary for corneal transparency. The purpose of this work is to study the in vitro assembly of collagen type V and to determine whether the interactions of these collagens influence fibril morphology.

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