scholarly journals A Preliminary Study on the Ability of the Trypsin-Like Peptidase Activity Assay Kit to Detect Periodontitis

2020 ◽  
Vol 8 (3) ◽  
pp. 98
Author(s):  
Masanori Iwasaki ◽  
Michihiko Usui ◽  
Wataru Ariyoshi ◽  
Keisuke Nakashima ◽  
Yoshie Nagai-Yoshioka ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Operating Characteristic ◽  
Area Under The Curve ◽  
Population Based ◽  
Case Definition ◽  
Peptidase Activity ◽  
Activity Assay ◽  
Severe Periodontitis ◽  
Study Population ◽  
Preliminary Study

This study aimed to explore whether the Trypsin-Like Peptidase Activity Assay Kit (TLP-AA-Kit), which measures the activity of N-benzoyl-dl-arginine peptidase (trypsin-like peptidase), can be used as a reliable tool for periodontitis detection in population-based surveillance. In total, 105 individuals underwent a full-mouth periodontal examination and provided tongue swabs as specimens for further analyses. The results of the TLP-AA-Kit were scored between 1 and 5; higher scores indicated higher trypsin concentrations. Receiver operating characteristic analyses were used to evaluate the predictive validity of the TLP-AA-Kit, where the periodontitis case definition provided by the Centers for Disease Control/American Academy of Periodontology served as the reference. Severe and moderate periodontitis were identified in 4.8% and 16.2% of the study population, respectively. The TLP-AA-Kit showed high diagnostic accuracy for severe periodontitis, with an area under the curve of 0.93 (95% confidence interval = 0.88–0.99). However, the diagnostic accuracy of the TLP-AA-Kit for moderate/severe periodontitis was not reliable. While further studies are necessary to validate our results, the results provided herein highlight the potential of the TLP-AA-Kit as a useful tool for the detection of periodontitis, particularly in severe cases, for population-based surveillance.

scholarly journals Evaluation of the ability of the trypsin-like peptidase activity assay to detect severe periodontitis

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256538
Author(s):  
Masanori Iwasaki ◽  
Michihiko Usui ◽  
Wataru Ariyoshi ◽  
Keisuke Nakashima ◽  
Yoshie Nagai-Yoshioka ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Characteristic Curve ◽  
Case Definition ◽  
Epidemiological Surveillance ◽  
Peptidase Activity ◽  
Regression Analyses ◽  
Activity Assay ◽  
A Value ◽  
Multivariable Logistic Regression ◽  
Severe Periodontitis

Objectives N-benzoyl-DL-arginine peptidase (trypsin-like peptidase) is specifically produced by certain strains of periodontitis-associated bacteria. We aimed to examine the effectiveness of an objectively quantified trypsin-like peptidase activity assay (TLP-AA) for detecting severe periodontitis. Methods The study population included 347 adults (108 men and 239 women; average age, 43.3 years) who underwent a full-mouth periodontal examination. Specimens for the TLP-AA were obtained using tongue swabs. Using a color reader, the TLP-AA results were obtained as a* values, with higher positive a* values indicating an increased intense enzymatic activity. The predictive validity of the TLP-AA results for severe periodontitis was assessed using receiver operating characteristic curve analysis and the periodontitis case definition provided by the Centers for Disease Control and Prevention/American Academy of Periodontology as the gold standard. Furthermore, multivariable logistic regression analyses were performed to predict severe periodontitis using the TLP-AA results and health characteristics, as the exposure variables. Results Severe periodontitis was observed in 5.2% of the participants. TLP-AA had high diagnostic accuracy for severe periodontitis, with an area under the curve of 0.83 (95% confidence interval [CI]: 0.75–0.92). The cut-off score for the a* value that best differentiated individuals with severe periodontitis was 0.09, with a sensitivity of 83% and specificity of 77%. Multivariable logistic regression analyses revealed that the TLP-AA results were significantly associated with severe periodontitis after adjusting for health characteristics (adjusted odds ratios: 1.90 [95% CI: 1.37–2.62] for the a* value). Conclusions Objectively quantified TLP-AA results are potentially useful for detecting severe periodontitis in epidemiological surveillance.

The potential value of a pictorial atlas for aid in the visual diagnosis of 123I FP-CIT SPECT scans

2009 ◽  
Vol 48 (04) ◽  
pp. 173-178 ◽  
Author(s):  
H. Ham ◽  
A. Dobbeleir ◽  
P. Santens ◽  
Y. D'Asseler ◽  
I. Goethals
Keyword(s):  
Diagnostic Accuracy ◽  
Roc Analysis ◽  
Operating Characteristic ◽  
Interobserver Variability ◽  
Area Under The Curve ◽  
Visual Assessment ◽  
Added Value ◽  
Related Disorder ◽  
Visual Diagnosis ◽  
Spect Images

SummaryThe aim of our study was to evaluate the value of a pictorial atlas of 123I FP-CIT SPECT images for aid in the visual diagnosis. Patients, materials, methods: Sixty patients, of whom 20 were clinically diagnosed as ‘non-parkinsonian’ and 40 as having Parkinson's disease or any related disorder, were included in the study. An atlas consisting of 12 123I FP-CIT SPECT images was constructed first. Validity of the atlas was investigated by performing a receiver operating characteristic (ROC) analysis with the clinical diagnosis as the gold standard. The remaining 48 SPECT images were visually assessed twice by 5 observers, first with and secondly without consulting the atlas, or vice versa. The added value of the atlas was investigated by comparing the diagnostic accuracy and the interobserver variability for both methods. Results: ROC analysis performed on the atlas yielded an area under the curve of 1 for a threshold discriminating between clinically non-parkinsonian and parkinsonian patients that was situated between image 4 and 5 of the atlas. For the diagnostic accuracy, we found that the area under the ROC curve was systematically higher if observers had access to the atlas compared to when they had not (Wilcoxon's test, p<0.05). Also, the interobserver variability was significantly lower when observers used the atlas when compared to when they did not (p = 0.05). Conclusion: Diagnostic accuracy was significantly higher and interobserver variability significantly lower if observers had access to the atlas compared to when they had not. Hence, having a pictorial atlas available may facilitate the visual assessment of 123I FP-CIT SPECT scans.

scholarly journals Upregulation of the RNF8 gene can predict the presence of sperm in azoospermic individuals

2020 ◽  
Vol 47 (1) ◽  
pp. 61-67
Author(s):  
Majid Nazari ◽  
Emad Babakhanzadeh ◽  
S. Mohsen Aghaei Zarch ◽  
Mehrdad Talebi ◽  
Nima Narimani ◽  
...  
Keyword(s):  
Operating Characteristic ◽  
Characteristic Curve ◽  
Area Under The Curve ◽  
Testicular Biopsy ◽  
Negative Group ◽  
Nonobstructive Azoospermia ◽  
Entire Study ◽  
Biopsy Specimens ◽  
Study Population ◽  
Polymerase Chain

Objective: In this study, specimens from testicular biopsies of men with nonobstructive azoospermia (NOA) were used to investigate whether <i>RNF8</i> gene could serve as a biomarker to predict the presence of sperm in these patients.Methods: Testicular biopsy specimens from 47 patients were classified according to the presence of sperm (positive vs. negative groups) and investigated for the expression of <i>RNF8</i>. The level of <i>RNF8</i> gene expression in the testes was compared between these groups using reverse-transcription polymerase chain reaction.Results: The expression level of <i>RNF8</i> was significantly higher in testicular samples from the positive group than in those from the negative group. Moreover, the area under the curve of <i>RNF8</i> expression for the entire study population was 0.84, showing the discriminatory power of <i>RNF8</i> expression in differentiating between the positive and negative groups of men with NOA. A receiver operating characteristic curve analysis showed that <i>RNF8</i> expression had a sensitivity of 81% and a specificity of 84%, with a cutoff level of 1.76.Conclusion: This study points out a significant association between the expression of <i>RNF8</i> and the presence of sperm in NOA patients, which suggests that quantified <i>RNF8</i> expression in testicular biopsy samples may be a valuable biomarker for predicting the presence of spermatozoa in biopsy samples.

scholarly journals Inflammatory Breast Carcinoma: Elevated microRNA miR-181b-5p and Reduced miR-200b-3p, miR-200c-3p, and miR-203a-3p Expression as Potential Biomarkers with Diagnostic Value

Biomolecules ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1059
Author(s):  
Sarah Atef Fahim ◽  
Mahmoud Salah Abdullah ◽  
Nancy A. Espinoza-Sánchez ◽  
Hebatallah Hassan ◽  
Ayman M. Ibrahim ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Diagnostic Accuracy ◽  
Operating Characteristic ◽  
Area Under The Curve ◽  
Roc Curves ◽  
Diagnostic Value ◽  
Differentially Expressed Mirnas ◽  
E Box ◽  
Aggressive Breast Cancer ◽  
Potential Biomarkers

Inflammatory breast cancer (IBC) is a rare yet aggressive breast cancer variant, associated with a poor prognosis. The major challenge for IBC is misdiagnosis due to the lack of molecular biomarkers. We profiled dysregulated expression of microRNAs (miRNAs) in primary samples of IBC and non-IBC tumors using human breast cancer miRNA PCR array. We discovered that 28 miRNAs were dysregulated (10 were upregulated, while 18 were underexpressed) in IBC vs. non-IBC tumors. We identified 128 hub genes, which are putative targets of the differentially expressed miRNAs and modulate important cancer biological processes. Furthermore, our qPCR analysis independently verified a significantly upregulated expression of miR-181b-5p, whereas a significant downregulation of miR-200b-3p, miR-200c-3p, and miR-203a-3p was detected in IBC tumors. Receiver operating characteristic (ROC) curves implied that the four miRNAs individually had a diagnostic accuracy in discriminating patients with IBC from non-IBC and that miR-203a-3p had the highest diagnostic value with an AUC of 0.821. Interestingly, a combination of miR-181b-5p, miR-200b-3p, and miR-200c-3p robustly improved the diagnostic accuracy, with an area under the curve (AUC) of 0.897. Intriguingly, qPCR revealed that the expression of zinc finger E box-binding homeobox 2 (ZEB2) mRNA, the putative target of miR-200b-3p, miR-200c-3p, and miR-203a-3p, was upregulated in IBC tumors. Overall, this study identified a set of miRNAs serving as potential biomarkers with diagnostic relevance for IBC.

Evaluation of Serum GDF15, AFP, and PIVKA-II as Diagnostic Markers for HBV-Associated Hepatocellular Carcinoma

2020 ◽  
Author(s):  
Juanjuan Chen ◽  
Dongling Tang ◽  
Chu Xu ◽  
Zhili Niu ◽  
Huan Li ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Hepatitis B ◽  
Diagnostic Accuracy ◽  
Roc Curve ◽  
Operating Characteristic ◽  
Area Under The Curve ◽  
Serum Levels ◽  
Diagnostic Value ◽  
Serum Marker ◽  
B Virus

Abstract Objective To evaluate the potential diagnostic value of growth differentiation factor 15 (GDF15) alone and its combination with protein induced by vitamin K absence-II (PIVKA-II) and alpha-fetoprotein (AFP) for hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). Methods Serum levels of GDF15, PIVKA-II, and AFP were measured in 110 patients with HBV-associated HCC, 70 patients with HBV-related liver cirrhosis (LC), 70 patients with chronic hepatitis B (CHB), and 110 healthy patients. Results Serum GDF15 was positively related to the levels of PIVKA-II and AFP in patients with HCC (r = 0.352 and r = 0.378; all P &lt;.0001). When the receiver operating characteristic (ROC) curve was plotted for patients with HCC vs all control patients, serum GDF15 had diagnostic parameters of an area under the curve (AUC) of 0.693, a sensitivity of 67.30%, and a specificity of 66.70%, which were lower than parameters for PIVKA-II and AFP (all P &lt;.0001). When the ROC curve was plotted for patients with HCC vs patients with LC, the combination of GDF15 and PIVKA-II had the highest diagnostic accuracy of AUC and specificity as compared with other combinations (all P &lt;.0001). Conclusion We found that GDF15 is a potent serum marker for the detection of HBV-associated HCC and that PIVKA-II combined with GDF15 can improve diagnostic accuracy for HBV-associated HCC.

scholarly journals Validation of a commercially available SARS-CoV-2 serological Immunoassay

2020 ◽  
Author(s):  
Benjamin Meyer ◽  
Giulia Torriani ◽  
Sabine Yerly ◽  
Lena Mazza ◽  
Adrien Calame ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Predictive Value ◽  
Operating Characteristic ◽  
Neutralization Assay ◽  
Case Control ◽  
Immunofluorescence Assay ◽  
Assay Performance ◽  
Study Population ◽  
Rule Out

AbstractObjectivesTo validate the diagnostic accuracy of a Euroimmun SARS-CoV-2 IgG and IgA immunoassay for COVID-19.MethodsIn this unmatched (1:1) case-control validation study, we used sera of 181 laboratory-confirmed SARS-CoV-2 cases and 176 controls collected before SARS-CoV-2 emergence. Diagnostic accuracy of the immunoassay was assessed against a whole spike protein-based recombinant immunofluorescence assay (rIFA) by receiver operating characteristic (ROC) analyses. Discrepant cases between ELISA and rIFA were further tested by pseudo-neutralization assay.ResultsCOVID-19 patients were more likely to be male and older than controls, and 50.3% were hospitalized. ROC curve analyses indicated that IgG and IgA had high diagnostic accuracies with AUCs of 0.992 (95% Confidence Interval [95%CI]: 0.986-0.996) and 0.977 (95%CI: 0.963-0.990), respectively. IgG assays outperformed IgA assays (p=0.008). Taking an assessed 15% inter-assay imprecision into account, an optimized IgG ratio cut-off > 1.5 displayed a 100% specificity (95%CI: 98–100) and a 100% positive predictive value (95%CI: 97-100). A 0.5 cut-off displayed a 97% sensitivity (95%CI: 93–99) and a 97% negative predictive value (95%CI: 93–99). Substituting these thresholds for the manufacturer’s, improved assay performance, leaving 12% of IgG ratios indeterminate between 0.5-1.5.ConclusionsThe Euroimmun assay displays a nearly optimal diagnostic accuracy using IgG against SARS-CoV-2 in patient samples, with no obvious gains from IgA serology. The optimized cut-offs are fit for rule-in and rule-out purposes, allowing determination of whether individuals in our study population have been exposed to SARS-CoV-2 or not. IgG serology should however not be considered as a surrogate of protection at this stage.

scholarly journals Is kallikrein-8 a blood biomarker for detecting amnestic mild cognitive impairment? Results of the population-based Heinz Nixdorf Recall study

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Sara Schramm ◽  
Martha Jokisch ◽  
Karl-Heinz Jöckel ◽  
Arne Herring ◽  
Kathy Keyvani
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Operating Characteristic ◽  
Area Under The Curve ◽  
Population Based ◽  
Amnestic Mild Cognitive Impairment ◽  
Population Based Study ◽  
Blood Biomarker ◽  
Heinz Nixdorf Recall Study ◽  
Potential Clinical Utility

Abstract Background Kallikrein-8 (KLK8) might be an early blood-biomarker of Alzheimer’s disease (AD). We examined whether blood KLK8 is elevated in persons with amnestic mild cognitive impairment (aMCI) which is a precursor of AD, compared to cognitively unimpaired (CU) controls. Methods Forty cases and 80 controls, matched by sex and age (± 3years), were participants of the longitudinal population-based Heinz Nixdorf Recall study (baseline: 2000–2003). Standardized cognitive performance was assessed 5 (T1) and 10 years after baseline (T2). Cases were CU at T1 and had incidental aMCI at T2. Controls were CU at T1 and T2. Blood KLK8 was measured at T2. Using multiple logistic regression the association between KLK8 in cases vs. controls was investigated by estimating odds ratios (OR) and 95% confidence intervals (95%CI), adjusted for inter-assay variability and freezing duration. Using receiver operating characteristic (ROC) analysis, the diagnostic accuracy of KLK8 was determined by estimating the area under the curve (AUC) and 95%CI (adjusted for inter-assay variability, freezing duration, age, sex). Results Thirty-seven participants with aMCI vs. 72 CU (36.7%women, 71.0±8.0 (mean±SD) years) had valid KLK8 measurements. Mean KLK8 was higher in cases than in controls (911.6±619.8 pg/ml vs.783.1±633.0 pg/ml). Fully adjusted, a KLK8 increase of 500pg/ml was associated with a 2.68 (1.05–6.84) higher chance of having aMCI compared to being CU. With an AUC of 0.92 (0.86–0.97), blood KLK8 was a strong discriminator for aMCI and CU. Conclusion This is the first population-based study to demonstrate the potential clinical utility of blood KLK8 as a biomarker for incipient AD.

Classical (adiponectin, leptin, resistin) and new (chemerin, vaspin, omentin) adipocytokines in patients with prediabetes

2018 ◽  
Vol 0 (0) ◽  
Author(s):  
Antoaneta Gateva ◽  
Yavor Assyov ◽  
Adelina Tsakova ◽  
Zdravko Kamenov
Keyword(s):  
Insulin Resistance ◽  
Predictive Value ◽  
Operating Characteristic ◽  
Area Under The Curve ◽  
Serum Adiponectin ◽  
Endocrine Organ ◽  
Serum Leptin ◽  
Discriminating Power ◽  
Study Population ◽  
Obese Subjects

Abstract Background In the last decade, there has been an increased interest toward fat tissue as an endocrine organ that secretes many cytokines and bioactive mediators that play a role in insulin sensitivity, inflammation, coagulation and the pathogenesis of atherosclerosis. The aim of this study was to investigate classical (adiponectin, leptin, resistin) and new (chemerin, vaspin, omentin) adipocytokine levels in subjects with prediabetes [impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT)] and obese subjects with normoglycemia. Methods In this study, 80 patients with a mean age of 50.4 ± 10.6 years were recruited, divided into two groups with similar age and body mass index (BMI) – with obesity and normoglycemia (n = 41) and with obesity and prediabetes (n = 39). Results Serum adiponectin levels were significantly higher in subjects with normoglycemia compared to patients with prediabetes. Adiponectin has a good discriminating power to distinguish between patients with and without insulin resistance in our study population [area under the curve (AUC) = 0.728, p = 0.002]. Other adipocytokine levels were not significantly different between the two groups. The patients with metabolic syndrome (MetS) had significantly lower levels of leptin compared to those without MetS (33.03 ± 14.94 vs. 40.24 ± 12.23 ng/mL) and this difference persisted after adjustment for weight and BMI. Receiver operating characteristic (ROC) analysis showed that low serum leptin can predict the presence of MetS (p = 0.03), AUC = 0.645. Conclusion Serum adiponectin is statistically higher in patients with normoglycemia compared to those with prediabetes and has a predictive value for distinguishing between patients with and without insulin resistance in the studied population. Serum leptin has a good predictive value for distinguishing between patients with and without MetS in the studied population.

scholarly journals Proteolyzed Variant of IgG with Free C-Terminal Lysine as a Biomarker of Prostate Cancer

Biology ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 817
Author(s):  
Anna Lokshin ◽  
Lyudmila M. Mikhaleva ◽  
Eugene I. Goufman ◽  
Marina N. Boltovskaya ◽  
Natalia B. Tikhonova ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Diagnostic Accuracy ◽  
Conformational Changes ◽  
Operating Characteristic ◽  
Area Under The Curve ◽  
Enzyme Linked Immunosorbent Assay ◽  
Healthy Controls ◽  
Human Plasminogen ◽  
Total Psa ◽  
Circulating Levels

The differential diagnosis of prostate cancer is problematic due to the lack of markers with high diagnostic accuracy. We previously demonstrated the increased binding of IgG to human plasminogen (PLG) in plasma of patients with prostate cancer (PC) compared to healthy controls. Heavy and light chains of PLG (PLG-H and PLG-L) were immobilized on 96-well plates and the binding of IgG to PLG-H and PLG-L was analyzed in serum from 30 prostate cancer (PC) patients, 30 patients with benign prostatic hyperplasia (BPH) and 30 healthy controls using enzyme-linked immunosorbent assay (ELISA). Our results demonstrate that IgG from PC sera bind to PLG-H but not to PLG-L. This interaction occurred through the free IgG C-terminal lysine (Lys) that becomes exposed as a result of IgG conformational changes associated with proteolysis. Circulating levels of modified IgG with exposed C-terminal Lys (IgG-Lys) were significantly higher in PC patients than in healthy controls and in BPH. We used Receiver Operating Characteristic (ROC) analysis to calculate the sensitivity (SN) and specificity (SP) of circulating IgG-Lys for differentiating PC from BPH as 77% and 90%, respectively. The area under the curve (AUC) was 0.87. We demonstrated that the diagnostic accuracy of circulating levels of IgG-Lys is much higher than diagnostic accuracy of total PSA (tPSA).

scholarly journals A risk stratification approach for improved interpretation of diagnostic accuracy statistics

2016 ◽  
Author(s):  
Hormuzd A. Katki ◽  
Mark Schiffman
Keyword(s):  
Public Health ◽  
Risk Stratification ◽  
Diagnostic Accuracy ◽  
Area Under The Curve ◽  
Population Based ◽  
Screening Tests ◽  
Predictive Values ◽  
The Usa ◽  
Relative Gains ◽  
Youden’S Index

AbstractDiagnostic accuracy statistics, including predictive values, risk-differences, Youden’s index and Area Under the Curve (AUC), assess the promise of novel biomarkers proposed as diagnostic tests. We reinterpret these statistics in light of risk-stratification (how well a biomarker separates those at higher risk from those at lower risk) to better understand their implications for public-health programs. We introduce an intuitively simple statistic, Mean Risk Stratification (MRS): the average change in risk (pre-test vs. post-test) revealed for tested individuals. High MRS implies better risk separation achieved by testing. MRS demonstrates that conventional predictive values can mislead because they do not account for disease prevalence or test-positivity rates. Little risk-stratification is possible for rare diseases, demonstrating a “high-bar” to justify population-based screening. Importantly, we demonstrate that the risk-difference, Youden’s index, and AUC measure only multiplicative relative gains in risk-stratification: AUC=0.6 achieves only 20% of maximum risk-stratification (AUC=0.9 achieves 80%). However, large relative gains in risk-stratification might not imply large absolute gains if disease is rare or if the test is rarely positive. We illustrate MRS by our experience comparing the performance of cervical cancer screening tests in China vs. the USA. The test with the worst AUC=0.72 in China (visual inspection with ascetic acid) provides twice the risk-stratification of the test with best AUC=0.83 in the USA (human papillomavirus and Pap cotesting) because China has three times more cervical precancer/cancer. MRS could be routinely calculated to better understand the clinical/public-health implications of standard diagnostic accuracy statistics.

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