Role of Salivary Biomarkers in Detection of Cardiovascular Diseases (CVD)

Proteomic profiling of extracellular vesicles derived from human serum for the discovery of biomarkers in Avascular necrosis

BACKGROUND

Avascular necrosis (AVN) is a medical condition characterized by the destruction of bone tissue due to a diminished blood supply. When the rate of tissue destruction surpasses the rate of regeneration, effective treatment becomes challenging, leading to escalating pain, arthritis, and bone fragility as the disease advances. A timely diagnosis is imperative to prevent and initiate proactive treatment for osteonecrosis. We explored the potential of differentially expressed proteins in serum-derived extracellular vesicles (EVs) as biomarkers for AVN of the femoral head in humans. We analyzed the genetic material contained in serum-derived exosomes from patients for early diagnosis, treatment, and prognosis of avascular necrosis.

METHODS

EVs were isolated from the serum of both patients with AVN and a control group of healthy individuals. Proteomic analyses were conducted to compare the expression patterns of these proteins by proteomic analysis using LC-MS/MS.

RESULTS

Our results show that the levels of IGHV3-23, FN1, VWF, FGB, PRG4, FCGBP, and ZSWIM9 were upregulated in the EVs of patients with AVN compared with those of healthy controls. ELISA results showed that VWF and PRG4 were significantly upregulated in the patients with AVN.

CONCLUSIONS

These findings suggest that these EV proteins could serve as promising biomarkers for the early detection and diagnosis of AVN. Early diagnosis is paramount for effective treatment, and the identification of new osteonecrosis biomarkers is essential to facilitate swift diagnosis and proactive intervention. Our study provides novel insights into the identification of AVN-related biomarkers that can enhance clinical management and treatment outcomes.

Understanding exosomes: Part 3-therapeutic + diagnostic potential in dentistry

Exosomes are the smallest subset of extracellular signaling vesicles secreted by most cells with the ability to communicate with other tissues and cell types over long distances. Their use in regenerative medicine has gained tremendous momentum recently due to their ability to be utilized as therapeutic options for a wide array of various diseases. Over 5000 publications are currently being published on this topic yearly, many of which in the dental space. This extensive review article is the first scoping review aimed at summarizing all therapeutic uses of exosomes in regenerative dentistry. A total of 944 articles were identified as using exosomes in the dental field for either their regenerative/therapeutic potential or for diagnostic purposes derived from the oral cavity. In total, 113 research articles were selected for their regenerative potential (102 in vitro, 60 in vivo, 50 studies included both). Therapeutic exosomes were most commonly derived from dental pulps, periodontal ligament cells, gingival fibroblasts, stem cells from exfoliated deciduous teeth, and the apical papilla which have all been shown to facilitate the regenerative potential of a number of tissues including bone, cementum, the periodontal ligament, nerves, aid in orthodontic tooth movement, and relieve temporomandibular joint disorders, among others. Results demonstrate that the use of exosomes led to positive outcomes in 100% of studies. In the bone field, exosomes were found to perform equally as well or better than rhBMP2 while significantly reducing inflammation. Periodontitis animal models were treated with simple gingival injections of exosomes and benefits were even observed when the exosomes were administered intravenously. Exosomes are much more stable than growth factors and were shown to be far more resistant against degradation by periodontal pathogens found routinely in a periodontitis environment. Comparative studies in the field of periodontal regeneration found better outcomes for exosomes even when compared to their native parent stem cells. In total 47 diagnostic studies revealed a role for salivary/crevicular fluid exosomes for the diagnosis of birth defects, cardiovascular disease, diabetes, gingival recession detection, gingivitis, irritable bowel syndrome, neurodegenerative disease, oral lichen planus, oral squamous cell carcinoma, oropharyngeal cancer detection, orthodontic root resorption, pancreatic cancer, periodontitis, peri-implantitis, Sjögren syndrome, and various systemic diseases. Hence, we characterize the exosomes as possessing "remarkable" potential, serving as a valuable tool for clinicians with significant advantages.

Biomarkers and optical based biosensors in cardiac disease detection: early and accurate diagnosis

Rapid and precise detection methods for the early-stage detection of cardiovascular irregularities are crucial to stopping and reducing their development. Cardiovascular diseases (CVDs) are the leading cause of death in the world. Hence, cardiac-related biomarkers are essential for monitoring and managing of process. The necessity for biomarker detection has significantly widened the field of biosensor development. Bio-sensing methods offer rapid detection, low cost, sensitivity, portability, and selectivity in the development of devices for biomarker detection. For the prediction of cardiovascular diseases, some biomarkers can be used, like C-reactive protein (CRP), troponin I or T, creatine kinase (CK-MB), B-type natriuretic peptide (BNP), myoglobin (Mb), suppression of tumorigenicity 2 protein (ST2) and galectin-3 (Gal3). In this review, recent research studies were covered for gaining insight into utilizing optical-based biosensors, including surface plasmon resonance (SPR), photonic crystals (PCs), fluorescence-based techniques, fiber optics, and also Raman spectroscopy biosensors for the ultrasensitive detection of cardiac biomarkers. The main goal of this review is to focus on the improvement of optical biosensors in the future for the diagnosis of heart diseases and to discuss how to enhance their properties for use in medicine. Some main data from each study reviewed are emphasized, including the CVD biomarkers and the response range of the optical-based devices and biosensors.

The Potential Role of Salivary NT-proBNP in Heart Failure

BACKGROUND

Serum natriuretic peptides (NPs) have an established role in heart failure (HF) diagnosis. Saliva NT-proBNP that may be easily acquired has been studied little.

METHODS

Ninety-nine subjects were enrolled; thirty-six obese or hypertensive with dyspnoea but no echocardiographic HF findings or raised NPs served as controls, thirteen chronic HF (CHF) patients and fifty patients with acute decompensated HF (ADHF) requiring hospital admission. Electrocardiogram, echocardiogram, 6 min walking distance (6MWD), blood and saliva samples, were acquired in all participants.

RESULTS

Serum NT-proBNP ranged from 60-9000 pg/mL and saliva NT-proBNP from 0.64-93.32 pg/mL. Serum NT-proBNP was significantly higher in ADHF compared to CHF (p = 0.007) and in CHF compared to controls (p < 0.05). There was no significant difference in saliva values between ADHF and CHF, or between CHF and controls. Saliva and serum levels were positively associated only in ADHF patients (R = 0.352, p = 0.012). Serum NT-proBNP was positively associated with NYHA class (R = 0.506, p < 0.001) and inversely with 6MWD (R = -0.401, p = 0.004) in ADHF. Saliva NT-proBNP only correlated with age in ADHF patients.

CONCLUSIONS

In the current study, saliva NT-proBNP correlated with serum values in ADHF patients, but could not discriminate between HF and other causes of dyspnoea. Further research is needed to explore the value of saliva NT-proBNP.

Periodontitis and cardiovascular risk factors in subjects with and without type 1 diabetes: A cross sectional analysis

AIMS

This cross-sectional analysis explored the relationships between periodontal disease (PD) and subclinical CVD in a cohort of patients with type 1 diabetes and non-diabetic controls.

METHODS

Data were collected from adults enrolled in the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study or enrolled through the Barbara Davis Center for Diabetes Adult Clinic. A clinical periodontal exam measured attachment loss and probing depth. Brachial artery distensibility (brachD), carotid intima-media thickness (cIMT), and pulse wave velocity (PWV) were assessed as measures of subclinical cardiovascular structure and function.

RESULTS

144 participants with T1D and 148 non-diabetics were enrolled. Compared to non-diabetic controls, T1D participants had a higher probing depth (2.6 mm vs. 2.5 mm; p = 0.04), higher attachment loss (2.7 mm vs. 2.4 mm; p < 0.01), lower brachD (mean 5.8 vs. 6.4 mmHg; p < 0.01), a higher cIMT (mean 0.68 vs. 0.64 mm; p < 0.01), and a higher PWV (mean 8.3 vs. 7.8 m/s; p < 0.01). There were no significant associations between PD and CVD metrics.

CONCLUSIONS

Periodontal and cardiovascular health was worse in participants with T1D compared to non-diabetics. No significant associations between PD measures and CVD were identified.

Salivary biomarkers: novel noninvasive tools to diagnose chronic inflammation

Several chronic disorders including type 2 diabetes (T2D), obesity, heart disease and cancer are preceded by a state of chronic low-grade inflammation. Biomarkers for the early assessment of chronic disorders encompass acute phase proteins (APP), cytokines and chemokines, pro-inflammatory enzymes, lipids and oxidative stress mediators. These substances enter saliva through the blood flow and, in some cases, there is a close relation between their salivary and serum concentration. Saliva can be easily collected and stored with non-invasive and cost-saving procedures, and it is emerging the concept to use it for the detection of inflammatory biomarkers. To this purpose, the present review aims to discuss the advantages and challenges of using standard and cutting-edge techniques to discover salivary biomarkers which may be used in diagnosis/therapy of several chronic diseases with inflammatory consequences with the pursuit to possibly replace conventional paths with detectable soluble mediators in saliva. Specifically, the review describes the procedures used for saliva collection, the standard approaches for the measurement of salivary biomarkers and the novel methodological strategies such as biosensors to improve the quality of care for chronically affected patients.

A Review on Saliva-Based Health Diagnostics: Biomarker Selection and Future Directions

The human body has a unique way of saying when something is wrong with it. The molecules in the body fluids can be helpful in the early detection of diseases by enabling health and preventing disease progression. These biomarkers enabling better healthcare are becoming an extensive area of research interest. Biosensors that detect these biomarkers are becoming the future, especially Point Of Care (POC) biosensors that remove the need to be physically present in the hospital. Detection of complex and systemic diseases using biosensors has a long way to go. Saliva-based biosensors are gaining attention among body fluids due to their non-invasive collection and ability to detect periodontal disease and identify systemic diseases. The possibility of saliva-based diagnostic biosensors has gained much publicity, with companies sending home kits for ancestry prediction. Saliva-based testing for covid 19 has revealed effective clinical use and relevance of the economic collection. Based on universal biomarkers, the detection of systemic diseases is a booming research arena. Lots of research on saliva-based biosensors is available, but it still poses challenges and limitations as POC devices. This review paper talks about the relevance of saliva and its usefulness as a biosensor. Also, it has recommendations that need to be considered to enable it as a possible diagnostic tool.

Graphical Abstract

Metabolic Pathway of Cardiospecific Troponins: From Fundamental Aspects to Diagnostic Role (Comprehensive Review)

Many molecules of the human body perform key regulatory functions and are widely used as targets for the development of therapeutic drugs or as specific diagnostic markers. These molecules undergo a significant metabolic pathway, during which they are influenced by a number of factors (biological characteristics, hormones, enzymes, etc.) that can affect molecular metabolism and, as a consequence, the serum concentration or activity of these molecules. Among the most important molecules in the field of cardiology are the molecules of cardiospecific troponins (Tns), which regulate the processes of myocardial contraction/relaxation and are used as markers for the early diagnosis of ischemic necrosis of cardiomyocytes (CMC) in myocardial infarction (MI). The diagnostic value and diagnostic capabilities of cardiospecific Tns have changed significantly after the advent of new (highly sensitive (HS)) detection methods. Thus, early diagnostic algorithms of MI were approved for clinical practice, thanks to which the possibility of rapid diagnosis and determination of optimal tactics for managing patients with MI was opened. Relatively recently, promising directions have also been opened for the use of cardiospecific Tns as prognostic markers both at the early stages of the development of cardiovascular diseases (CVD) (arterial hypertension (AH), heart failure (HF), coronary heart disease (CHD), etc.), and in non-ischemic extra-cardiac pathologies that can negatively affect CMC (for example, sepsis, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), etc.). Recent studies have also shown that cardiospecific Tns are present not only in blood serum, but also in other biological fluids (urine, oral fluid, pericardial fluid, amniotic fluid). Thus, cardiospecific Tns have additional diagnostic capabilities. However, the fundamental aspects of the metabolic pathway of cardiospecific Tns are definitively unknown, in particular, specific mechanisms of release of Tns from CMC in non-ischemic extra-cardiac pathologies, mechanisms of circulation and elimination of Tns from the human body, mechanisms of transport of Tns to other biological fluids and factors that may affect these processes have not been established. In this comprehensive manuscript, all stages of the metabolic pathway are consistently and in detail considered, starting from release from CMC and ending with excretion (removal) from the human body. In addition, the possible diagnostic role of individual stages and mechanisms, influencing factors is analyzed and directions for further research in this area are noted.

Aptamers Targeting Cardiac Biomarkers as an Analytical Tool for the Diagnostics of Cardiovascular Diseases: A Review

The detection of cardiac biomarkers is used for diagnostics, prognostics, and the risk assessment of cardiovascular diseases. The analysis of cardiac biomarkers is routinely performed with high-sensitivity immunological assays. Aptamers offer an attractive alternative to antibodies for analytical applications but, to date, are not widely practically implemented in diagnostics and medicinal research. This review summarizes the information on the most common cardiac biomarkers and the current state of aptamer research regarding these biomarkers. Aptamers as an analytical tool are well established for troponin I, troponin T, myoglobin, and C-reactive protein. For the rest of the considered cardiac biomarkers, the isolation of novel aptamers or more detailed characterization of the known aptamers are required. More attention should be addressed to the development of dual-aptamer sandwich detection assays and to the studies of aptamer sensing in alternative biological fluids. The universalization of aptamer-based biomarker detection platforms and the integration of aptamer-based sensing to clinical studies are demanded for the practical implementation of aptamers to routine diagnostics. Nevertheless, the wide usage of aptamers for the diagnostics of cardiovascular diseases is promising for the future, with respect to both point-of-care and laboratory testing.

Raman spectroscopy: current applications in breast cancer diagnosis, challenges and future prospects

Despite significant improvements in the way breast cancer is managed and treated, it continues to persist as a leading cause of death worldwide. If detected and diagnosed early, when tumours are small and localised, there is a considerably higher chance of survival. However, current methods for detection and diagnosis lack the required sensitivity and specificity for identifying breast cancer at the asymptomatic or very early stages. Thus, there is a need to develop more rapid and reliable methods, capable of detecting disease earlier, for improved disease management and patient outcome. Raman spectroscopy is a non-destructive analytical technique that can rapidly provide highly specific information on the biochemical composition and molecular structure of samples. In cancer, it has the capacity to probe very early biochemical changes that accompany malignant transformation, even prior to the onset of morphological changes, to produce a fingerprint of disease. This review explores the application of Raman spectroscopy in breast cancer, including discussion on its capabilities in analysing both ex-vivo tissue and liquid biopsy samples, and its potential in vivo applications. The review also addresses current challenges and potential future uses of this technology in cancer research and translational clinical application.

The Importance of Cardiac Troponin Metabolism in the Laboratory Diagnosis of Myocardial Infarction (Comprehensive Review)

The study of the metabolism of endogenous molecules is not only of great fundamental significance but also of high practical importance, since many molecules serve as drug targets and/or biomarkers for laboratory diagnostics of diseases. Thus, cardiac troponin molecules have long been used as the main biomarkers for confirmation of diagnosis of myocardial infarction, and with the introduction of high-sensitivity test methods, many of our ideas about metabolism of these cardiac markers have changed significantly. In clinical practice, there are opening new promising diagnostic capabilities of cardiac troponins, the understanding and justification of which are closely connected with the fundamental principles of the metabolism of these molecules. Our current knowledge about the metabolism of cardiac troponins is insufficient and extremely disconnected from various literary sources. Thus, many researchers do not sufficiently understand the potential importance of cardiac troponin metabolism in the laboratory diagnosis of myocardial infarction. The purpose of this comprehensive review is to systematize information about the metabolism of cardiac troponins and during the discussion to focus on the potential impact of cTns metabolism on the laboratory diagnosis of myocardial infarction. The format of this comprehensive review includes a sequential consideration and analysis of the stages of the metabolic pathway, starting from possible release mechanisms and ending with elimination mechanisms. This will allow doctors and researchers to understand the significant importance of cTns metabolism and its impact on the laboratory diagnosis of myocardial infarction.

Non-Invasive Assessment of Congestion by Cardiovascular and Pulmonary Ultrasound and Biomarkers in Heart Failure

Worsening chronic heart failure (HF) is responsible for recurrent hospitalization and increased mortality risk after discharge, irrespective to the ejection fraction. Symptoms and signs of pulmonary and systemic congestion are the most common cause for hospitalization of acute decompensated HF, as a consequence of increased cardiac filling pressures. The elevated cardiac filling pressures, also called hemodynamic congestion, may precede the occurrence of clinical congestion by days or weeks. Since HF patients often have comorbidities, dyspnoea, the main symptom of HF, may be also caused by respiratory or other illnesses. Recent studies underline the importance of the diagnosis and treatment of hemodynamic congestion before HF symptoms worsen, reducing hospitalization and improving prognosis. In this paper we review the role of integrated evaluation of biomarkers and imaging technics, i.e., echocardiography and pulmonary ultrasound, for the diagnosis, prognosis and treatment of congestion in HF patients.

Biology of Cardiac Troponins: Emphasis on Metabolism

Simple Summary

Cardiovascular diseases, including myocardial infarction, are among the most common diseases worldwide. Markers associated with the diagnosis of myocardial infarction have been in the spotlight for many years. The most commonly used markers of myocardial infarction are cardiac troponins. However, insufficient understanding of the biology and metabolism of cardiac troponins does not allow us to fully unlock the full diagnostic potential of these cardiomarkers. In this article, I summarized and discussed in detail the features of the metabolism of cardiac troponins. I conducted a comprehensive review of current literary sources and presented my point of view. The format of the manuscript includes a consistent description of the biology and stages of the metabolism of cardiac troponins, starting from the release and circulation, and ending with the features of elimination of cardiac troponins. The possible influence of the biology of cardiac troponins on the diagnostic value of cardiac troponins is analyzed. Based on the analysis of the literature, I found a close relationship between the diagnostic value of cardiac troponins and their biology/metabolism. Further research is needed to increase the diagnostic value of cardiac troponins, and to fully unlock their diagnostic potential.

Abstract

Understanding of the biology of endo- and exogenous molecules, in particular their metabolism, is not only of great theoretical importance, but also of high practical significance, since many molecules serve as drug targets or markers for the laboratory diagnostics of many human diseases. Thus, cardiac troponin (cTns) molecules have long been used as key markers for the confirmation of diagnosis of myocardial infarction (MI), and with the introduction of contemporary (high sensitivity) test methods, many of our concepts related to the biology of these cardiac markers have changed significantly. In current clinical practice, there are opening new promising diagnostic capabilities of cTns, the understanding and justification of which is closely connected with the theoretical principles of the metabolism of these molecules. However, today, the biology and metabolism of cTns have not been properly investigated; in particular, we do not know the precise mechanisms of release of these molecules from the myocardial cells (MCs) of healthy people and the mechanisms of circulation, and the elimination of cTns from the bloodstream. The main purpose of this manuscript is to systematize information about the biology of cTns, with an emphasis on the metabolism of cTns. The format of this paper, starting with the release of cTns in the blood and concluding with the metabolism/filtration of troponins, provides a comprehensive yet logically easy way for the readers to approach our current knowledge in the framework of understanding the basic mechanisms by which cTns are produced and processed. Conclusions. Based on the analysis of the current literature, the important role of biology and all stages of metabolism (release, circulation, removal) of cTns in laboratory diagnostics should be noted. It is necessary to continue studying the biology and metabolism of cTns, because this will improve the differential diagnosis of MI and i a new application of cTns immunoassays in current clinical practice.

Microfluidic Point-of-Care (POC) Devices in Early Diagnosis: A Review of Opportunities and Challenges

The early diagnosis of infectious diseases is critical because it can greatly increase recovery rates and prevent the spread of diseases such as COVID-19; however, in many areas with insufficient medical facilities, the timely detection of diseases is challenging. Conventional medical testing methods require specialized laboratory equipment and well-trained operators, limiting the applicability of these tests. Microfluidic point-of-care (POC) equipment can rapidly detect diseases at low cost. This technology could be used to detect diseases in underdeveloped areas to reduce the effects of disease and improve quality of life in these areas. This review details microfluidic POC equipment and its applications. First, the concept of microfluidic POC devices is discussed. We then describe applications of microfluidic POC devices for infectious diseases, cardiovascular diseases, tumors (cancer), and chronic diseases, and discuss the future incorporation of microfluidic POC devices into applications such as wearable devices and telemedicine. Finally, the review concludes by analyzing the present state of the microfluidic field, and suggestions are made. This review is intended to call attention to the status of disease treatment in underdeveloped areas and to encourage the researchers of microfluidics to develop standards for these devices.

Dental Healthcare Amid the COVID-19 Pandemic

The hustle and bustle of the planet Earth have come to a halt thanks to the novel coronavirus. The virus has affected approximately 219 million people globally; taken the lives of 4.55 million patients as of September 2021; and created an ambiance of fear, social distancing, and economic instability. The purpose of this review article is to trace the historical origin and evolution of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). The virus is highly contagious with a unique feature of rapid mutations-the scientific research is paving the way for discoveries regarding novel coronavirus disease (COVID-19) diagnosis, features, prevention, and vaccination. The connections between the coronavirus pandemic and dental practices are essential because COVID-19 is transmitted by aerosols, fomites, and respiratory droplets, which are also produced during dental procedures, putting both the patient and the dentist at risk. The main emphasis of this paper is to highlight the psychological, economic, and social impact of this pandemic on dental practices throughout the world and under what circumstances and guidelines can dental health care be provided. In the current situation of the pandemic, an appropriate screening tool must be established either by using rapid molecular testing or saliva point-of-care technology, which will be effective in identifying as well as isolating the potential contacts and carriers in hopes to contain and mitigate infection. The blessing in disguise is that this virus has united the leaders, scientists, health care providers, and people of all professions from all around the world to fight against a common enemy.

Clinical Treatment Analysis and Imaging Study of Patients with Acute Angina in Cardiovascular Medicine

With the accelerating pace of life, increasing stress and unhealthy diet make cardiovascular disease one of the important diseases that endanger human health, among which the incidence of acute angina is gradually increasing. At present, there are many clinical treatment studies on acute angina pectoris, but the relevant imaging analysis is very lacking. In order to study the clinical treatment of patients with acute angina pectoris and analyze the relevant medical images, to arrive at a more effective treatment method, this article launched an in-depth study. First, we selected 88 patients with acute angina in a hospital as the research object and randomly divided them into a control group (n = 44) and an experimental group (n = 44) Yan et al. (2020). The control group was treated with conventional acute angina pectoris drugs, while the experimental group was treated with clopidogrel on this basis. The two groups were treated at the same time, and the treatment time lasted for 3 months. Then, the risk factors of the two groups of patients were analyzed, and the differences were statistically significant (P < 0.05). Then, the medical images of the two groups of patients were analyzed, and the diastolic blood pressure, systolic blood pressure, and coronary artery stenosis were compared before and after treatment. After treatment, the diastolic blood pressure and systolic blood pressure of the experimental group were 88.31 ± 3.15 mmHg and 125.63 ± 4.16 mmHg, respectively. The proportion of patients with zero-vessel disease and single-vessel disease in the experimental group increased to 15.91% and 56.82%. The treatment plan received by the experimental group patients had a better improvement effect. Finally, the clinical efficacy was compared. The total effective rates of the control and experimental groups were 72.7% and 88.6%, respectively. This shows that the treatment method adopted by the experimental group of patients has a better curative effect and is worthy of clinical promotion.

Serum-Derived Neuronal Exosomal miRNAs as Biomarkers of Acute Severe Stress

Stress is the physical and psychological tension felt by an individual while adapting to difficult situations. Stress is known to alter the expression of stress hormones and cause neuroinflammation in the brain. In this study, miRNAs in serum-derived neuronal exosomes (nEVs) were analyzed to determine whether differentially expressed miRNAs could be used as biomarkers of acute stress. Specifically, acute severe stress was induced in Sprague-Dawley rats via electric foot-shock treatment. In this acute severe-stress model, time-dependent changes in the expression levels of stress hormones and neuroinflammation-related markers were analyzed. In addition, nEVs were isolated from the serum of control mice and stressed mice at various time points to determine when brain damage was most prominent; this was found to be 7 days after foot shock. Next-generation sequencing was performed to compare neuronal exosomal miRNA at day 7 with the neuronal exosomal miRNA of the control group. From this analysis, 13 upregulated and 11 downregulated miRNAs were detected. These results show that specific miRNAs are differentially expressed in nEVs from an acute severe-stress animal model. Thus, this study provides novel insights into potential stress-related biomarkers.

Microfluidic integrated capacitive biosensor for C-reactive protein label-free and real-time detection

A microfluidic chip has been integrated with a capacitive biosensor based on mass-producible three-dimensional (3D) interdigital electrode arrays. To achieve the monitoring of biosensor preparation and cardiac- and periodontitis-related biomarkers, all the processes were detected in a continuously on-site way. Fabrication steps for the microfluidic chip-bonded 3D interdigital capacitor biosensor include gold thiol modification, the activation of EDC/sulfo-NHS, and the bioconjugation of antibodies. Fluorescent characterization and X-ray photoelectron spectroscopy analysis were applied to assess the successful immobilization of the C-reactive protein (CRP) antibody. The experimental results indicate the good specificity and high sensitivity of the microfluidic integrated 3D capacitive biosensor. The limit of detection of the 3D capacitive biosensor for CRP label-free detection was about 1 pg mL^-1. This 3D capacitive biosensor with integrated microfluidics is mass-producible and has achieved the on-site continuous detection of cardiac- and periodontitis-related biomarkers with high performance.

Differential Glycosylation Levels in Saliva from Patients with Lung or Breast Cancer: A Preliminary Assessment for Early Diagnostic Purposes

Glycans play a fundamental role in several biological processes, such as cell-cell adhesion, signaling, and recognition. Similarly, abnormal glycosylation is involved in many pathological processes, among which include tumor growth and progression. Several highly glycosylated proteins found in blood are currently used in clinical practice as cancer biomarkers (e.g., CA125, PSA, and CA19-9). The development of novel non-invasive diagnostic procedures would greatly simplify the screening and discovery of pathologies at an early stage, thus also allowing for simpler treatment and a higher success rate. In this observational study carried out on 68 subjects diagnosed with either breast or lung cancer and 34 healthy volunteers, we hydrolyzed the glycoproteins in saliva and quantified the obtained free sugars (fucose, mannose, galactose, glucosamine, and galactosamine) by using high-performance anion-exchange chromatography with pulsed-amperometric detection (HPAEC-PAD). The glycosidic profiles were compared by using multivariate statistical analysis, showing differential glycosylation patterns among the three categories. Furthermore, Receiver Operating Characteristics (ROC) analysis allowed obtaining a reliable and minimally invasive protocol able to discriminate between healthy and pathological subjects.

Emerging Role of Epigenetics in Explaining Relationship of Periodontitis and Cardiovascular Diseases

Cardiovascular diseases such as ischemic heart diseases or stroke are among the leading cause of deaths globally, and evidence suggests that these diseases are modulated by a multifactorial and complex interplay of genetic, environmental, and lifestyle factors. Genetic predisposition and chronic exposure to modifiable risk factors have been explored to be involved in the pathophysiology of CVD. Environmental factors contribute to an individual's propensity to develop major cardiovascular risk factors through epigenetic modifications of DNA and histones via miRNA regulation of protein translation that are types of epigenetic mechanisms and participate in disease development. Periodontal disease (PD) is one of the most common oral diseases in humans that is characterized by low-grade inflammation and has been shown to increase the risk of CVDs. Risk factors involved in PD and CVD are determined both genetically and behaviorally. Periodontal diseases such as chronic inflammation promote DNA methylation. Epigenetic modifications involved in the initiation and progression of atherosclerosis play an essential role in plaque development and vulnerability. Epigenetics has opened a new world to understand and manage human diseases, including CVDs and periodontal diseases. Genetic medicine has started a new era of epigenetics to overcome human diseases with various new methodology. Epigenetic profiling may aid in better diagnosis and stratification of patients showing potential predisposed states for disease. A better understanding of the exact regulatory mechanisms of epigenetic pathways driving inflammation is slowly emerging and will aid in developing novel tools for the treatment of disease.

New biomarkers from multiomics approaches: improving risk prediction of atrial fibrillation

Atrial fibrillation (AF) is a common cardiac arrhythmia leading to many adverse outcomes and increased mortality. Yet the molecular mechanisms underlying AF remain largely unknown. Recent advances in high-throughput technologies make large-scale molecular profiling possible. In the past decade, multiomics studies of AF have identified a number of potential biomarkers of AF. In this review, we focus on the studies of multiomics profiles with AF risk. We summarize recent advances in the discovery of novel biomarkers for AF through multiomics studies. We also discuss limitations and future directions in risk assessment and discovery of therapeutic targets for AF.

Effect of Serum on Electrochemical Detection of Bioassays Having Ag Nanoparticle Labels

The effect of serum on electrochemical detection of bioassays having silver nanoparticle (AgNP) detection labels was investigated. Both a model assay and an antigen-specific sandwich bioassay for the heart failure marker NT-proBNP were examined. In both cases, the AgNP labels were conjugated to a detection antibody. Electrochemical detection was carried out using a galvanic exchange/anodic stripping voltammetry method in which Au3+ exchanges with AgNP labels. The assays were carried out using a paper-based electrode platform. The bioassays were exposed to different serum conditions prior to and during detection. There are three important outcomes reported in this article. First, both the model- and antigen-specific assays could be formed in undiluted serum with no detectable interferences from the serum components. Second, to achieve the maximum possible electrochemical signal, the highest percentage of serum that can remain in an assay buffer during electrochemical detection is 0.25% when no washing is performed. The assay results are rendered inaccurate when 0.50% or more of serum is present. Third, the factors inhibiting galvanic exchange in serum probably relate to surface adsorption of biomolecules onto the AgNP labels, chelation of Au3+ by serum components, or both. The results reported here provide general guidance for using metal NP labels for electrochemical assays in biofluids.

Salivary Biomarkers for Diagnosis and Therapy Monitoring in Patients with Heart Failure. A Systematic Review

The aim of this study was to perform a systematic review on the potential value of saliva biomarkers in the diagnosis, management and prognosis of heart failure (HF). The correlation between saliva and plasma values of these biomarkers was also studied. PubMed was searched to collect relevant literature, i.e., case-control, cross-sectional studies that either compared the values of salivary biomarkers among healthy subjects and HF patients, or investigated their role in risk stratification and prognosis in HF patients. No randomized control trials were included. The search ended on 31st of December 2020. A total of 15 studies met the inclusion criteria. 18 salivary biomarkers were analyzed and the levels of all biomarkers studied were found to be higher in HF patients compared to controls, except for amylase, sodium, and chloride that had smaller saliva concentrations in HF patients. Natriuretic peptides are the most commonly used plasma biomarkers in the management of HF. Their saliva levels show promising results, although the correlation of saliva to plasma values is weakened in higher plasma values. In most of the publications, differences in biomarker levels between HF patients and controls were found to be statistically significant. Due to the small number of patients included, larger studies need to be conducted in order to facilitate the use of saliva biomarkers in clinical practice.

Salivary Immunoglobulin Gamma-3 Chain C Is a Promising Noninvasive Biomarker for Systemic Lupus Erythematosus

We aimed to characterize the salivary protein components and identify biomarkers in patients with systemic lupus erythematosus (SLE). A proteomic analysis using two-dimensional gel electrophoresis and mass spectrometry was performed to determine the alterations of salivary proteins between patients with SLE and healthy controls, and the concentrations of the candidate proteins were measured through Western blot analysis and the enzyme-linked immunosorbent assay. The 10 differentially expressed protein spots were immunoglobulin gamma-3 chain C region (IGHG3), immunoglobulin alpha-1 chain C region, protein S100A8, lactoferrin, leukemia-associated protein 7, and 8-oxoguanine DNA glycosylase. The patients with SLE exhibited enhanced salivary IGHG3 (3.9 ± 2.15 pg/mL) and lactoferrin (4.7 ± 1.8 pg/mL) levels compared to patients with rheumatoid arthritis (1.8 ± 1.01 pg/mL and 3.2 ± 1.6 pg/mL, respectively; p < 0.001 for both) or healthy controls (2.2 ± 1.64 pg/mL and 2.2 ± 1.7 pg/mL, respectively; p < 0.001 for both). The salivary IGHG3 levels correlated with the erythrocyte sedimentation rate (r = 0.26, p = 0.01), anti-double-stranded DNA (dsDNA) antibody levels (r = 0.25, p = 0.01), and nephritis (r = 0.28, p = 0.01). The proteomic analysis revealed that the salivary IGHG3 levels were associated with SLE and lupus disease activity, suggesting that salivary IGHG3 may be a promising noninvasive biomarker for SLE.

Electrochemical sensing: A prognostic tool in the fight against COVID-19

The COVID-19 pandemic has devastated the world, despite all efforts in infection control and treatment/vaccine development. Hospitals are currently overcrowded, with health statuses of patients often being hard to gauge. Therefore, methods for determining infection severity need to be developed so that high-risk patients can be prioritized, resources can be efficiently distributed, and fatalities can be prevented. Electrochemical prognostic biosensing of various biomarkers may hold promise in solving these problems as they are low-cost and provide timely results. Therefore, we have reviewed the literature and extracted the most promising biomarkers along with their most favourable electrochemical sensors. The biomarkers discussed in this paper are C-reactive protein (CRP), interleukins (ILs), tumour necrosis factor alpha (TNFα), interferons (IFNs), glutamate, breath pH, lymphocytes, platelets, neutrophils and D-dimer. Metabolic syndrome is also discussed as comorbidity for COVID-19 patients, as it increases infection severity and raises chances of becoming infected. Cannabinoids, especially cannabidiol (CBD), are discussed as a potential adjunct therapy for COVID-19 as their medicinal properties may be desirable in minimizing the neurodegenerative or severe inflammatory damage caused by severe COVID-19 infection. Currently, hospitals are struggling to provide adequate care; thus, point-of-care electrochemical sensor development needs to be prioritized to provide an approximate prognosis for hospital patients. During and following the immediate aftermath of the pandemic, electrochemical sensors can also be integrated into wearable and portable devices to help patients monitor recovery while returning to their daily lives. Beyond the COVID-19 pandemic, these sensors will also prove useful for monitoring inflammation-based diseases such as cancer and cardiovascular disease.

COVID-19 Pandemic and Role of Human Saliva as a Testing Biofluid in Point-of-Care Technology

Novel coronavirus disease 2019 (COVID-19) outbreak has termed as a controllable pandemic, and the entire world has come to a standstill trying to mitigate the disease with health systems. Health care providers, around the globe, are fighting day and night. Currently, rapid testing is taking place with the help of nasopharyngeal, oropharyngeal swab, bronchoalveolar lavage, sputum, urine, and blood. All these approaches are invasive or embarrassing to the infected person. It is observed that salivary glands are hosting severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) because of angiotensin-converting enzyme 2 and the detection of high viral loads in the saliva and is playing a crucial role in virus transmission, especially from individuals showing absolutely no symptoms. Saliva is proving to be a promising noninvasive sample specimen for the diagnosis of COVID-19, thus helping to monitor the infection and prevent it from further spreading by prompt isolation.

Ultrasensitive detection of interleukin 1α using 3-phosphonopropionic acid modified FTO surface as an effective platform for disposable biosensor fabrication

In this study, we utilized a carboxyalkylphosphonic acid covered fluorine doped tin oxide (FTO) as an electrode material for fabrication of Interleukin 1α (IL-1α) immunosensor. For this aim, anti-IL-1α antibodies were attached on the 3-phosphonopropionic acid (PHP) modified FTO surface covalently. Electrochemical (electrochemical impedance spectroscopy and cyclic voltammetry) and morphological (scanning electron microscopy and atomic force microscopy) characterizations were performed to monitor the successful fabrication of immunoelectrodes. After incubation of anti-IL-1α antibody immobilized FTO electrodes in IL-1α antigen solutions, increases were seen in impedimetric responses. IL-1α antigen was determined in a linear detection range from 0.02 to 2 pg/mL by EIS. The detection limit of the suggested immunosensor was 6 fg/mL. The applicability of the designed biosensor was tested by using human serum and saliva samples and acceptable results were obtained. In addition, high sensitivity, good specificity, low detection limit made the proposed immunosensor a potential technique for IL-1α antigen determination in routine clinical analysis.

Salivary Extracellular DNA and DNase Activity in Periodontitis

Extracellular DNA (ecDNA) is a potential marker and predictor in several inflammatory diseases. Periodontitis, a chronic inflammatory disease, is associated with epithelial cell death and could lead to release of DNA. Our aim was to analyze salivary DNA concentration and deoxyribonuclease (DNase) activity in periodontitis patients. We hypothesized that salivary ecDNA will be higher than in controls and could serve as a marker of periodontitis severity. Samples of saliva were collected from 25 patients with chronic periodontitis and 29 age-matched controls. DNA was quantified fluorometrically in whole saliva, as well as in supernatants after centrifugation (depletion of cells at 1600× g) and in double-centrifuged supernatants (depletion of cell debris at 1600× g and 16,000× g). The subcellular origin of ecDNA was assessed using real-time PCR. In comparison to controls, patients with periodontitis had twofold higher salivary DNA (p < 0.01), higher mitochondrial DNA in centrifuged supernatants (p < 0.05) and lower nuclear ecDNA in double-centrifuged samples (p < 0.05). No correlations were found between salivary DNA and oral health status, but mitochondrial DNA positively correlated with papillary bleeding index in centrifuged samples. Salivary DNase activity was comparable between the groups. In conclusion, we proved that salivary DNA is higher in periodontitis. The source of the higher mitochondrial DNA in cell-free saliva and the causes of lower nuclear ecDNA remain to be elucidated. Further studies should focus on the role of mitochondrial DNA as a potential driver of inflammation in periodontitis.

Biochemical analysis of oral fluids for disease detection

The field of diagnostics using invasive blood testing represents the majority of diagnostic tests used as part of routine health monitoring. The relatively recent introduction of salivary diagnostics has lead to a major paradigm shift in diagnostic analyses. Additionally, in this era of big data, oral fluid testing has shown promising outcomes in a number of fields, particularly the areas of genomics, microbiomics, proteomics, metabolomics, and transcriptomics. Despite the analytical challenges involved in the interpretation of large datasets generated from biochemical studies involving bodily fluids, including saliva, many studies have identified novel oral biomarkers for diagnosing oral and systemic diseases. In this regard, oral biofluids, including saliva, gingival crevicular fluid (GCF), peri-implant crevicular fluid (PICF), dentinal tubular fluid (DTF), are now attracting increasing attention due to their important attributes, such as noninvasive sampling, easy handling, low cost, and more accurate diagnosis of oral diseases. Recently, the utilization of salivary diagnostics to evaluate systemic diseases and monitor general health has increased in popularity among clinicians. Saliva contains a wide range of protein, DNA and RNA biomarkers, which assist in the diagnosis of multiple diseases and conditions, including cancer, cardiovascular diseases (CVD), auto-immune and degenerative diseases, respiratory infections, oral diseases, and microbial (viral, bacterial and fungal) diseases. Moreover, due to its noninvasive nature and ease-of-adoption by children, it is now being used in mass screening programs, oral health-related studies and clinical trials in support of the development of therapeutic agents. The recent advent of highly sensitive technologies, such as next-generation sequencing, mass spectrometry, highly sensitives ELISAs, and homogeneous immunoassays, suggests that even small quantities of salivary biomarkers are able to be assayed accurately, providing opportunities for the development of many future diagnostic applications (including emerging technologies, such as point-of-care and rapid molecular technologies). The present article explores the omics and biochemical compositions of various oral biofluids with important value in diagnostics and monitoring.

Evaluation of Osteocalcin Levels in Saliva of Periodontitis Patients and Their Correlation with the Disease Severity: A Cross-Sectional Study

OBJECTIVES

 The present study aimed to investigate osteocalcin levels in saliva of healthy and periodontitis patients and correlate these levels with periodontitis severity.

MATERIALS AND METHODS

 This cross-sectional study was conducted in a hospital setup. A total of 95 individuals participated in the study with 46 subjects in group I (healthy individuals) and 49 subjects in group II (mild, moderate, and severe chronic periodontitis patients). A detailed assessment of clinical periodontal parameters and alveolar bone loss was made. Unstimulated saliva samples were collected from all study subjects and osteocalcin levels were quantitatively analyzed by sandwich enzyme-linked immunosorbent essay technique.

STATISTICAL ANALYSIS

 One-way analysis of variance, Spearman's correlation test, and Pearson's chi-squared test were applied at a significance level of 95%. p-Values less than 0.05 were considered statistically significant.

RESULTS

 The results showed a significant association of qualification with group II (p < 0.02). Bone loss scores were also significantly associated with periodontitis severity (p < 0.01). However, no statistically significant difference was observed between group I and group II in terms of mean salivary osteocalcin levels (p = 0.68). Also, an insignificant correlation was also observed between osteocalcin levels and periodontitis severity (p = 0.13).

CONCLUSION

 The overall study results showed that there was no significant difference between saliva osteocalcin levels of healthy and periodontitis patients. Also, there was a nonsignificant correlation between osteocalcin levels and periodontitis severity. The findings of the present study support the hypothesis that low osteocalcin levels in saliva might be considered as a poor indicator of periodontal disease progression and severity.

Nanoscale Technologies in Highly Sensitive Diagnosis of Cardiovascular Diseases

Cardiovascular diseases (CVD) are the leading cause of death and morbidity in the world and are a major contributor to healthcare costs. Although enormous progress has been made in diagnosing CVD, there is an urgent need for more efficient early detection and the development of novel diagnostic tools. Currently, CVD diagnosis relies primarily on clinical symptoms based on molecular imaging (MOI) or biomarkers associated with CVDs. However, sensitivity, specificity, and accuracy of the assay are still challenging for early-stage CVDs. Nanomaterial platform has been identified as a promising candidate for improving the practical usage of diagnostic tools because of their unique physicochemical properties. In this review article, we introduced cardiac biomarkers and imaging techniques that are currently used for CVD diagnosis. We presented the applications of various nanotechnologies on diagnosis within cardiac immunoassays (CIAs) and molecular imaging. We also summarized and compared different cardiac immunoassays based on their sensitivities and working ranges of biomarkers.

Salivary Redox Biomarkers in Selected Neurodegenerative Diseases

Neurodegenerative diseases (NDDs), such as Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease, are disorders, which cause irreversible and progressive deterioration of the central nervous system. The pathophysiology of NDDs is still not fully explained; nevertheless, oxidative stress is considered as a critical mediator of cerebral degeneration, brain inflammation, as well as neuronal apoptosis. Therefore, it is not surprising that redox biomarkers are increasingly used in the diagnosis of neurodegenerative diseases. As saliva is a very easy to obtain bioliquid, it seems promising to use this biomaterial in the diagnosis of NDDs. Saliva collection is easy, cheap, stress-free, and non-infectious, and it does not require the help of a specialised medical personnel. Additionally, the concentrations of many salivary redox biomarkers correlate with their content in blood serum as well as the degree of disease progression, which makes them non-invasive indicators of NDDs. This paper reviews the latest knowledge concerning the use of salivary redox biomarkers in the diagnosis and prognosis of selected neurodegenerative diseases.

Diagnostic value of salivary CRP and IL-6 in patients undergoing anti-TNF-alpha therapy for rheumatic disease

Introduction

Saliva has been increasingly used as a diagnostic medium for disease detection and monitoring. The aim of this observational, prospective, pilot study was to investigate whether salivary concentrations of CRP and IL-6 correlate with those in serum and with the clinical course of a rheumatic disease.

Materials and methods

Nineteen patients with rheumatic disease newly scheduled for anti-TNFα therapy were included. Patients received anti-TNFα treatment (adalimumab, certolizumab, golimumab or infliximab) as per standard protocols. CRP and IL-6 were measured with high-sensitivity immunoassays before and after 12 weeks of therapy, according to standard regimens. The data were analyzed with nonparametric statistics.

Results

Concentrations of CRP in saliva correlated significantly with those in serum (R = 0.62; p < 0.0001) and decreased markedly after successful response to treatment. In patients with a limited response to treatment salivary CRP levels increased. In contrast to CRP, the salivary concentrations of IL-6 did not change significantly over the course of therapy and they did not correlate with serum IL-6 concentrations. Salivary levels of neither CRP nor IL-6 corresponded to parameters of oral health and hygiene.

Conclusions

Salivary CRP but not IL-6 could be of potential use for monitoring the rheumatic disease activity.

The Clinical Significance and Potential Role of C-Reactive Protein in Chronic Inflammatory and Neurodegenerative Diseases

C-reactive protein (CRP) is an acute-phase protein synthesized by hepatocytes in response to pro-inflammatory cytokines during inflammatory/infectious processes. CRP exists in conformationally distinct forms such as the native pentameric CRP and monomeric CRP (mCRP) and may bind to distinct receptors and lipid rafts and exhibit different functional properties. It is known as a biomarker of acute inflammation, but many large-scale prospective studies demonstrate that CRP is also known to be associated with chronic inflammation. This review is focused on discussing the clinical significance of CRP in chronic inflammatory and neurodegenerative diseases, such as cardiovascular disease, type 2 diabetes mellitus, age-related macular degeneration, hemorrhagic stroke, Alzheimer’s disease, and Parkinson’s disease, including recent advances on the implication of CRP and its forms specifically on the pathogenesis of these diseases. Overall, we highlight the advances in these areas that may be translated into promising measures for the diagnosis and treatment of inflammatory diseases.