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Skin and platelet alpha-synuclein as peripheral biomarkers of Parkinson's disease.

Parkinson's disease (PD) is a heterogeneous disease that can be difficult to diagnose, and for which we have no simple effective biomarker. In this study we have investigated whether peripheral alpha-synuclein might represent a useful biomarker given that it has a central role in the pathogenesis of PD. We found that full length and truncated alpha-synuclein is present in platelets, but the amount is very variable and does not correlate with disease presence or severity. Furthermore, we show that alpha-synuclein can be detected by immunoblotting in some, but not all, human skin biopsies, but again its level does not correlate with disease presence or severity. We conclude that skin or platelet alpha-synuclein would not be an appropriate diagnostic biomarker for PD.

Biomarkers↗

Physiologically based modeling of 1,2,4-trimethylbenzene inhalation toxicokinetics.

A physiologically based toxicokinetic model was developed for inhalation exposure of 1,2,4-trimethylbenzene (TMB) in man. The model consists of six compartments for TMB and one compartment for the metabolite 3,4-dimethylhippuric acid (DMHA). Based on previous experimental findings from human exposures to TMB, liver metabolism was divided in two pathways, one of the first order and one of the Michaelis-Menten type. Muscle tissue was split in two compartments to account for working and resting muscle tissues during bicycle exercise. The model was used to investigate how various factors influence potential biomarkers of exposure, i.e., TMB in blood and exhaled air and DMHA in urine. Increasing the work load from rest to moderate exercise (100 W) more than doubled all biomarker levels end of shift. The effect on next morning levels was even more pronounced, illustrated by a fivefold increase in the DMHA excretion rate. Simulations of five daily 8-h exposures suggest that biomarker levels end of shift remain fairly constant whereas the levels prior to shift increase gradually during the week. This suggests that end of shift levels reflect the exposure of the same day whereas levels Friday morning reflect exposure during the entire working week. Simulations with randomly generated exposures show that the variability due to fluctuating exposure is lower next morning than end of shift. End of shift exhalation rate of TMB is more sensitive to fluctuation than TMB in venous blood and DMHA in urine. Biomarker levels for 25 ppm exposure at different sampling times are given.

Administration, Inhalation↗

Bone marrow infiltration pattern in B-cell chronic lymphocytic leukemia is related to immunoglobulin heavy-chain variable region mutation status and expression of 70-kd zeta-associated protein (ZAP-70).

B-cell chronic lymphocytic leukemia (B-CLL) consists of at least 2 subtypes with either somatically mutated or unmutated immunoglobulin heavy-chain variable region (IgVH) genes. A prognostic significance of the infiltration pattern in bone marrow trephine biopsy has been described before. The combined pattern analysis and detection of 70-kd zeta-associated protein (ZAP-70) expression in formalin-fixed, paraffin-embedded bone marrow trephines has not been investigated so far. To evaluate the relationship between ZAP-70 expression, mutation status, and the infiltration pattern in B-CLL, we analyzed bone marrow trephine biopsies from B-CLL patients (n = 35). The expression of ZAP-70 was related to the infiltration type: in all samples with diffuse infiltration pattern, the leukemic cells showed ZAP-70 staining, whereas leukemic cells in a nodular infiltration pattern were negative. By contrast, the mixed-pattern type showed a variable ZAP-70 expression. Besides definitely negative or positive ZAP-70 expression, a few samples showed a faint ZAP-70 staining, and the classification into the positive or negative group was difficult. In addition, the infiltration type was related to the mutation status in a subset of samples: mutation of the IgVH gene was restricted to the nondiffuse infiltration pattern and was not found in cases with diffuse infiltration of bone marrow. The expression of ZAP-70, detected by an immunohistochemical assay and also by real-time quantitative reverse transcriptase-polymerase chain reaction assigned 83% of the chronic lymphocytic leukemia cases to the suspected immunoglobulin mutation subtype. In 2 patients with ZAP-70 expression, a mutated IgVH status was found. These cases exhibited a mixed pattern of infiltration. We conclude that the pure nodular type of marrow infiltration in B-CLL is associated with IgH hypermutation and ZAP-70 negativity, whereas the predominantly diffuse type of infiltration reveals unmutated IgH genes with ZAP-70 overexpression. The mixed type of infiltration is displayed by mutated as well as unmutated cases with a varying pattern of ZAP-70 expression.

Adult↗

The randomized controlled trial in studies using biomarkers.

The randomized controlled trial (RCT) is a scientific experiment during which observations on the effects of therapy or a preventive action are conducted by the researcher under rigorous control. The purpose of the experiment is to clear the uncertainties surrounding a clinical/research issue and involves isolating the 'treatment' and 'end result' variables from external influences. RCTs therefore make use of scientific method standards: measuring, which includes the possibility of reproducing observations; controlling factors unconnected to the cause-effect relationship of interest; and the external verification or 'falsification' of the cause-effect relationship. Many RCTs are now including biomarkers to answer scientific questions in a more accurate way. In the present methodological paper, the main aspects involved in the design and conduction of a trial are discussed, with special emphasis on the use of biomarkers. Aspects that are often overlooked by scientists involved in the design of trials include multiple comparisons, subgroup analysis, the duration of the observations, the use of surrogate endpoints, and ethical issues. This review summarizes the main issues that should be addressed in a protocol, and illustrates these with an example.

Biomarkers↗

[Validity of chromosome analysis and bleomycin sensitivity assay in the prevention of head and neck cancer in Hungary].

Because of unfavourable cancer mortality statistics of Hungary, the search of different biomarkers is one of the most important demands of the national primary cancer prevention programme. The aim of this study was to clarify the usefulness of bleomycin sensitivity assay elaborated in the USA, and to find whether it serves under our environmental conditions as a biomarker of individual sensitivity and risk for head and neck cancer, beside chromosomal aberration analysis. The test reflecting mutagen sensitivity is based on the mean values of chromatid breaks induced by bleomycin in vitro in a single lymphocyte (break/cell = b/c). Since cancer formation is influenced by environmental mutagens, in contrast to others, their 111 head and neck cancer patients were matched not only with 230 healthy controls (106 nonsmokers and 124 smokers), but also with 44 strong alcoholic and smoking patients with liver diseases whose lifestyle did not differ from that of the cancer patients. According to the results of conventional chromosome analysis, the aberrant cell frequency was the highest in the cancer patients (3.34%), while in the alcoholics (2.73%) and healthy smokers (2.88%) the values were similar. Thus, the genetic instability occurring in the form of elevated rate of spontaneous chromosomal aberrations was mostly expressed in head and neck cancer patients. Mutagen sensitivity measured by the b/c values of bleomycin assay was significantly higher in both the cancer (1.16 b/c) and the alcoholic patients (1.34 b/c) compared with the controls (1.0 b/c). The bleomycin sensitivity assay, therefore, seems to be the biomarker not only of cancer, but also the disease of the same etiology such as alcohol-related liver disease. However the method is not suitable for the assessment of individual cancer risk because of the high variability of b/c values in each group, and their considerable overlapping with the controls. It can also be supported with extremely high mutagen sensitivity of Hungarian controls (63 and 67%), which is three-fold of US values (23%). The bleomycin sensitivity assay is not a selective biomarker if comparing to the controls, probably due to the action of more complex exposures under Hungarian environmental conditions. When estimating cancer risk, the results of conventional chromosome analysis offer more information than bleomycin sensitivity assay.

Adult↗

Defective surface expression of attractin on T cells in patients with common variable immunodeficiency (CVID).

The proliferative responses of T lymphocytes of a subset of patients with CVID are abnormally low. This may be due to abnormalities in extracellular interactions or signalling defects downstream from membrane-associated receptors. Demonstrating that the T cell receptor signalling was normal, we observed no abnormal pattern of activation-induced tyrosine phosphorylation in cells from CVID patients. Moreover, the addition of exogenous IL-2 increased the low proliferation to mitogens, thus indicating the integrity of the IL-2R signalling apparatus. Attractin is a rapidly expressed T cell activation antigen involved in forming an association between T cells and monocytes. Twenty-four to 48 h after activation by CD3 cross-linking, attractin expression was not up-regulated on the cells of CVID patients despite normal up-regulation of CD25 and CD26. On control cells, however, attractin expression was up-regulated together with CD25 and CD26. The addition of the purified 175-kD attractin was capable of restoring the proliferative response of peripheral blood mononuclear cells following CD3 X-L in the presence of suboptimal concentrations of rIL-2 (10 and 20 U/ml). The effect was dose-dependent with the maximal effect at a concentration of 500 ng/ml, and present at a concentration as low as 50 ng/ml. Due to the likely role of attractin in cell guidance and amplification of the immune response, our results indicate that the lack of up-regulation of the molecule in patients with CVID may in turn affect any further step of productive immune response. Our finding may also imply a potential therapeutic role for this novel molecule.

Adolescent↗

Biomarkers in diagnostic obstetric and gynecologic pathology: a review.

Until recently, the histologic diagnosis of obstetrical and gynecologic neoplasia was based principally on morphologic criteria. However, interobserver reproducibility for entities such as squamous intraepithelial, endometrial, and trophoblastic disease varies widely between observers. This inherent variability in interpretation between individuals has led to wide ranges in diagnostic precision between practices, and in many cases, between recognized experts. The advent of immunohistochemistry, and the more recent accelerated discovery of new genes and their functions has resulted in the discovery of cellular proteins or nucleic acids that are differentially expressed in tumors. When applied in conjunction with existing histologic criteria, these "biomarkers" have the potential to enhance diagnostic consistency and reproducibility. The gains expected are to practicing diagnostic pathologists (who will enjoy greater diagnostic consistency) and to academics (for whom biomarkers may uncover new pathways unappreciated by histologic diagnosis alone). However, fundamental to the success in both arenas will be critical analysis of the potential pitfalls in immunohistochemistry, strict validation of new markers as they arrive in the field, and a realistic view of their value in the laboratory management of obstetrical and gynecologic diseases.

Biomarkers, Tumor↗

The erythrosense as a real-time biomarker to reveal the presence of enhanced red blood cell aggregability in atherothrombosis.

Both anemia and inflammation might be present in individuals with atherothrombosis. We have evaluated the eventual influence of these 2 variables on the degree of erythrocyte adhesiveness/aggregation in the peripheral blood of 583 women and 402 men with various atherothrombotic risk factors and vascular events. It turned out that both anemia and inflammation (highly sensitive C-reactive protein concentrations) influence the degree of cell adhesiveness/aggregation and that there is no interaction between them. Thus, the degree of erythrocyte adhesiveness/aggregation might have the diagnostic advantage of being enhanced in individuals with atherothrombosis who have inflammation and no anemia as well as those who have anemia and no inflammation. These findings might help to turn a phenomenon of hemorheological relevance into a diagnostic tool for the detection of individuals at risk of an acute ischemic event.

Anemia↗

Multiomics approaches to cardiovascular disease: technological innovations and clinical translation.

Cardiovascular diseases (CVDs) remain the leading cause of global morbidity and mortality, reflecting a persistent gap between clinical phenotyping and the molecular mechanisms that govern disease initiation, progression, and interindividual variability. Recent advances in emerging technologies have fundamentally reshaped cardiovascular physiology by enabling high-resolution, cross-layer profiling of the heart and vasculature across genomic, epigenomic, transcriptomic, proteomic, metabolomic, lipidomic, glycomic, and fluxomic layers, increasingly at single-cell and spatial resolution. These approaches reveal CVD as a coordinated, multilayered process driven by dynamic interactions among cell types, regulatory programs, and metabolic states, rather than isolated gene-level defects. In this review, we synthesize how emerging multiomic, computational, and functional genomic technologies are redefining the study of cardiovascular disease across molecular, cellular, and tissue levels. We highlight recent innovations in single-cell and spatial atlases, long-read sequencing, proteomics and metabolomics, integrative data modeling, and functional omics approaches, including genome-scale perturbation screens and single-cell perturbation frameworks. These platforms enable mechanistic dissection of regulatory circuits, distinguish primary disease drivers from secondary adaptations, and directly assess therapeutic reversibility, advancing the field beyond associative biomarker discovery toward mechanism-guided target prioritization. We further discuss key methodological and translational challenges accompanying high-dimensional cardiovascular data, including preanalytical variability, control selection, temporal misalignment across molecular layers, population diversity, and reference bias. By integrating technological innovation with computational rigor and functional validation, this review frames emerging omics-enabled strategies as a unified, physiologically grounded framework for translating molecular insight into clinically meaningful cardiovascular phenotypes and advancing precision cardiovascular medicine.

Humans↗

The Gyrolab platform for immunogenicity assessment and biotherapeutic and biomarker analysis: technical advances and bioanalytical applications.

Gyrolab is an automated ligand‑binding assay platform designed for the quantification of proteins with high sensitivity and broad dynamic range. Its low minimum required dilution and microfluidic disc format enable efficient sample processing while maintaining assay robustness, making it a valuable tool across drug‑development stages. This review summarizes published applications of Gyrolab for pharmacokinetic and toxicokinetic analysis and immunogenicity assessment through anti‑drug antibody detection. In addition, the platform's high-volume assay discs have facilitated its use in biomarker studies, allowing quantification of low‑abundance analytes. Representative examples from the literature are presented together with key assay elements, including analytes, matrices, dynamic ranges, and critical reagents. Because assay replicates remain an important consideration for Gyrolab workflows, recent publications addressing singlet versus duplicate strategies and their impact on data interpretation are also discussed. Finally, we provide real analytical data visualized using a three‑dimensional Gyrolab viewer to illustrate variability in duplicate measurements and to highlight future opportunities for improving assay reliability.

Humans↗

Proliferating cell nuclear antigen (PCNA) expression as a prognostic indicator for renal cell carcinoma: comparison with tumour grade, mitotic index, and silver-staining nucleolar organizer region numbers.

Proliferating cell nuclear antigen (PCNA) expression in renal cell carcinoma (RCC) was determined by immunohistochemical staining using the PC10 clone. PCNA indices ranged from 2.4 to 53.1 per cent with mean indices of 12.6, 19.0, and 31.6 per cent for grades 1 to 3 RCC and 31.9 per cent for sarcomatoid RCC. There was a significant difference between the indices of grades 1 and 3 and grades 2 and 3 tumours and between grades 1 and 2 RCC and sarcomatoid RCC. AgNOR scores and mitotic indices were determined for each tumour and comparison of PCNA indices with mean AgNOR scores and mitotic indices showed only a weak correlation (PCNA/AgNOR r = 0.406, PCNA/mitotic index r = 0.315). Tumours were divided according to PCNA index (< or = 18 per cent and > 18 per cent) and there was a significant difference in survival between the two groups, for all cases, and for each of the Robson stages. Multivariate analysis using Cox's proportional hazard model showed PCNA index, tumour stage, and mean AgNOR score to be independent predictors of survival, while tumour grade and mitotic index were found to be dependent variables.

Antigens, Neoplasm↗

Role of creatinine clearance as a screening test in persons with spinal cord injury.

OBJECTIVES: To determine (1) the variability of annual creatinine clearance (C(Cr)) testing for subjects with chronic spinal cord injury (SCI) and (2) whether decisions to change neurogenic bladder management are made based on C(Cr) measurements. DESIGN: Retrospective chart review. SETTING: Inpatient Veterans Affairs SCI unit. PARTICIPANTS: The medical records of 70 men were consecutively selected for review from among 664 veterans enrolled in the SCI clinic. All patient charts had to have at least 5 C(Cr) tests performed within 10 years preceding the review. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Development of renal insufficiency and change in medical or bladder management of the patient, based on the results of the C(Cr) test. RESULTS: For individual patients, the results of 24-hour C(Cr) were highly variable from 1 evaluation to the next; the within-subject standard deviation (SD) for C(Cr) was 25.9mL/min. The within-subject SD for serum creatinine was 0.12mg/dL. For all comparisons of repeatability, variability, and reliability, serum creatinine was superior to C(Cr). No medical management decisions were made based on the result of the 24-hour creatinine clearance. Renal ultrasound results and postvoid bladder residuals were the major factors in changing medical management with regard to renal function preservation. CONCLUSIONS: The C(Cr) test has little value as a screening measure for renal disease in SCI patients because of its variability in serial testing.

Biomarkers↗

Elevated circulating levels of matrix metalloproteinase-9 in type 1 diabetic patients with and without retinopathy.

OBJECTIVE: Tissue expression pattern of matrix metalloproteinases (MMPs) and their inhibitors TIMPs indicate that microvascular complications of diabetes mellitus are associated with extracellular matrix remodelling. We investigated whether circulating levels of MMP-9 and TIMP-1 are altered in diabetic retinopathy and whether they might serve as biological markers of ocular complications in type 1 diabetes. RESEARCH DESIGN AND METHODS: We recruited 47 type 1 diabetic patients free of vascular complications (n=40) or with retinopathy (n=14). Patients with macroangiopathy, neuropathy and nephropathy were excluded. A group of nondiabetic control subjects (n=35) was also constituted for comparative purposes. Peripheral blood levels of MMP-9 and TIMP-1 were determined using immunoenzymatic assays. RESULTS: Type 1 diabetic subjects exhibited significantly higher circulating levels of both MMP-9 and MMP-9/TIMP-1 ratio, as well as a tendency to increased serum TIMP-1 levels relative to nondiabetic controls (p<0.001). Diabetic patients with retinopathy also displayed elevated systemic values of MMP-9 and MMP-9/TIMP-1 ratio when compared to patients without retinopathy (p<0.05). Logistic regression analysis identified diabetes duration firstly (P<0.01), and MMP-9 serum levels secondly (P<0.01) as significant and independent variables associated with the existence of retinopathy. CONCLUSIONS: Our data suggest that peripheral blood MMP-9 levels might serve as surrogate biomarkers of retinopathy in type 1 diabetic patients free of other vascular complications.

Adult↗

Exfoliated buccal and microdissected lung cell expression of antioxidant enzymes.

INTRODUCTION: An exfoliated buccal cell biomarker assay for antioxidant gene transcript levels was used to measure inter-tissue concordance with lung, and inter-subject variability in a lung cancer case-control study. METHODS: First, qualitative RNA-specific RT-PCR was used to compare expression in exfoliated buccal cells with that in laser microdissected lung tissue remote from the tumor from 14 individuals providing both specimens. RESULTS: There was complete [100% for quinone oxidoreductase 1 (NQO1), glutathione peroxidase (GPX), and superoxide dismutase 1 (SOD1)], or predominant [85.7% for catalase (CAT)] inter-tissue concordance for qualitative expression. Second, quantitative real-time RT-PCR for antioxidant enzyme transcript levels was performed in exfoliated buccal samples from these same 14 individuals, as well as 28 additional individuals providing buccal cells only, for a total of 42 buccal specimens (19 current smokers and 23 ex- or never-smokers), of whom 26 (61.39%) had a new diagnosis of lung cancer. DISCUSSION: Wide inter-individual expression differences for each gene transcript (>10(1)-10(4)-fold) were observed in the exfoliated buccal cells, unrelated to smoking and case-control status. In multivariate analyses, family history of tobacco-related malignancy correlated inversely with buccal NQO1 and CAT mRNA levels (p=0.003, p<0.001, respectively). This antioxidant expression trait may relate to family risk of cancer, but is notably unrelated to oxidant challenges inherent in cigarette smoke.

Adult↗

Surveillance in the management of the cancer patient with special reference to breast and colon cancer.

Senior surgeons of the Society of Surgical Oncology were surveyed concerning their followup practices for patients with colon and breast cancer and compared them with the recommendations in the current literature. Intensive followup is not indicated for patients with breast cancer patients and all surgeons agree by using physical examination and mammograms predominantly. Colon cancer followup was variable and the literature indicates a small survival advantage for intensive followup.

Biomarkers, Tumor↗

Sources, vertical fluxes, and accumulation of aliphatic hydrocarbons in coastal sediments of the Río de la Plata Estuary, Argentina.

Settling particles and underlying sediments collected at 1, 2.5 and 4 km off the metropolitan Buenos Aires coast were analyzed to evaluate the sources and accumulation of resolved (RES), unresolved (UCM), and biomarker aliphatic hydrocarbons. Sedimentary aliphatic concentrations (RES 0.11-14 microg x g(-1); UCM 0.1-800 microg x g(-1)) included variability associated with north-south gradients and an exponential offshore reduction. Highest concentrations were registered close to Buenos Aires port and sewer, compared to cleaner northern stations and southward sites affected by a seaward residue transport. Sediment traps deployed in the sewer area revealed large hydrocarbon (38 and 319 mg x m(-2) x day(-1), RES and UCM) and total organic carbon fluxes (29 +/- 26 g x m(-2) x day(-1). The composition of RES and hopanes evaluated by principal component analysis indicated a consistent offshore gradient defined bythe relative contribution of lower vs higher molecular weight components. Distant sites showed decreasing proportions of petrogenic n-C(17-26) alkanes, isoprenoids, and C(20-27) terpanes and relative enrichment of n-C(27,29,31,33) terrestrial plant alkanes and C(31-33) homohopanes. Sediment hydrocarbon profiles showed an average 2-fold reduction down to 20 cm depth with preferential removal of lower molecular weight components and enrichment of n-C(23-35) alkanes and hopanes. Sediment inventories and trap depositional fluxes indicate the accumulation of 5800-9700 tons of aliphatic hydrocarbons in the top 0-5 cm sediments with a strong interfacial alteration and selective preservation of refractory components: n-C(13-22) (1.0%) < isoprenoids (3.2%) < n-C(23-35) (6.1%) < hopanes (47%) approximately UCM (50%), compared to intermediate stability of organic carbon (12%) and quantitative preservation of polychlorinated biphenyls (PCBs) (91%).

Argentina↗

Circulating ICAM-1 (intercellular cell-adhesion molecule 1) is associated with early stages of atherosclerosis development and with inflammatory cytokines in healthy 58-year-old men: the Atherosclerosis and Insulin Resistance (AIR) study.

There is a lack of data on circulating levels of cell-adhesion molecules in relation to subclinical atherosclerosis measured in both the carotid and femoral arteries in humans. The aim of the present study was to investigate the relationship between clinically silent atherosclerosis and cell-adhesion molecules, and to explore the relationship between these molecules, C-reactive protein and the inflammatory cytokines interleukin-6, tumour necrosis factor-alpha (TNF-alpha), soluble TNF-alpha receptor p55 and soluble TNF-alpha receptor p75. The study group (n=391) consisted of clinically healthy 58-year-old men recruited from the general population. The results showed a positive trend between levels of soluble intercellular cell-adhesion molecule 1 (sICAM-1) and plaque occurrence in the carotid and femoral arteries (P=0.008), and also a univariate correlation between sICAM-1 levels and the composite variable of carotid and femoral intima-media thickness (P<0.001). When adjusted for other risk factors, the relationship between sICAM-1 and intima-media thickness no longer reached statistical significance. The level of sICAM-1 was associated with those of the pro-inflammatory cytokine TNF-alpha, its two soluble receptors, and also interleukin-6 and C-reactive protein. Levels of soluble E-selectin and vascular cell-adhesion molecule 1 (VCAM-1) showed weak or no association with subclinical atherosclerosis and inflammatory variables. Thus, in clinically healthy middle-aged men, levels of sICAM-1, but not of soluble VCAM-1 or E-selectin, were associated with both subclinical atherosclerosis and inflammatory variables.

Antigens, CD↗

Differentiation and characterization of B-cell precursors detected in the yolk sac and embryo body of embryos beginning at the 10- to 12-somite stage.

The embryonic sites in which progenitors of the hematopoietic lineages first emerge are ideal regions to characterize both the cells and environment needed to initiate blood cell development. For a number of years both the murine yolk sac and embryo have been recognized to contain progenitors of B lymphocytes. However, clonal, quantitative in vitro assays, which allow precise observation of precursors and their progeny, have been lacking. Moreover, the site of origin of the initial events remains controversial. In this report we document the presence of B-cell progenitors in yolk sac and embryonic tissue obtained from mouse fetuses beginning at the 10-somite stage, day 8.5. We determine the frequency, cell-surface phenotype, and growth properties of these progenitors. We show that these cells can differentiate into immunoglobulin-secreting cells and that the progeny derived from single progenitors are diverse with respect to immunoglobulin heavy-chain allotype expression, diversity-joining region use, and heavy-chain variable-region utilization.

Animals↗