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Background: The risk of developing a state of low energy availability (LEA) (<30 kcals/kg free-fat mass) in endurance athletes is known and recommendations for nutrition are available. However, information on male adolescent cyclists and the influence of hot temperatures is limited. Objectives: The aim of this study was to investigate the impact on energy availability of two 4-day nutritional intervention strategies: (1) supplementary carbohydrate (CHO) intake during exercise and (2) designing and implementing individual nutritional interventions. Methods: Each intervention was preceded by a 4-day basal assessment. Eight competitive male junior road cyclists (aged 16–17 years) were investigated using a 4-day diet and activity records, alongside bioelectric impedance analysis. Their real-time power output, interstitial glucose, and temperature were recorded via sensors and a bike computer. Their energy intake (EI) was estimated from daily, self-reported food diaries. Results: Overall, 100% and 71% of the cyclists were in a state of LEA during the baseline assessment of the supplementary CHO and nutritional interventions, respectively. LEA prevalence, not modified by supplementary CHO intake alone (from 100% to 87%, ns), was markedly reduced by the individual nutritional intervention (from 71% to 14%, p < 0.05). When considering all the data as a whole, LEA was positively influenced by the training load (OR 1.06; 95% Cl 1.03 to 1.09) and free-fat mass (OR 1.46; 1.04 to 2.04) and was negatively affected by EI (OR 0.994; 0.991 to 0.997). A hot environment (air temperature) failed to influence the LEA or glucose dynamics. Conclusions: the nutritional intervention, but not the supplementary CHO intake, markedly reduced the prevalence of LEA in adolescents, who often fail to match their energy expenditure with their energy intake during the competitive season. Nutritional education is essential for adolescent endurance cycling teams. [ABSTRACT FROM AUTHOR]

This review provides a comprehensive overview of point-of-care (PoC) devices across several key diagnostic applications, including blood analysis, infectious disease detection, neural interfaces, and commercialized integrated circuits (ICs). In the blood analysis section, the focus is on biomarkers such as glucose, dopamine, and aptamers, and their respective detection techniques. The infectious disease section explores PoC technologies for detecting pathogens, RNA, and DNA, highlighting innovations in molecular diagnostics. The neural interface section reviews advancements in neural recording and stimulation for therapeutic applications. Finally, a survey of commercialized ICs from companies such as Abbott and Medtronic is presented, showcasing existing PoC devices already in widespread clinical use. This review emphasizes the role of complementary metal-oxide-semiconductor (CMOS) technology in enabling compact, efficient diagnostic systems and offers insights into the current and future landscape of PoC devices. [ABSTRACT FROM AUTHOR]

Diabetes has emerged as a worldwide health crisis, affecting approximately 537 million adults. Maintaining blood glucose requires careful observation of diet, physical activity, and adherence to medications if necessary. Diet monitoring historically involves keeping food diaries; however, this process can be labor-intensive, and recollection of food items may introduce errors. Automated technologies such as food image recognition systems (FIRS) can make use of computer vision and mobile cameras to reduce the burden of keeping diaries and improve diet tracking. These tools provide various levels of diet analysis, and some offer further suggestions for improving the nutritional quality of meals. The current study is a systematic review of mobile computer vision-based approaches for food classification, volume estimation, and nutrient estimation. Relevant articles published over the last two decades are evaluated, and both future directions and issues related to FIRS are explored. [ABSTRACT FROM AUTHOR]

This study endeavored to design and develop an innovative closed-loop diagnostic and therapeutic system with the following objectives: (a) the noninvasive detection of glucose concentration in sweat utilizing nanonengineered screen-printed biosensors; (b) the management of measured data through a specialized computer system comprising both hardware and software components, thereby enabling the precise control of therapeutic responses via a patch-based nanomedicine delivery system. This initiative addresses the significant challenges inherent in the management of diabetes mellitus, including the imperative need for glucose-level monitoring to optimize glycemic control. Leveraging chronoamperometric results as a foundational dataset and the in vivo hypoglycemic activity of nanoemulsion formulations, this research underscores the efficacy and accuracy of glucose concentration estimation, decision-making mechanism responses, and transdermal hypoglycemic treatment effects, within the proposed system. [ABSTRACT FROM AUTHOR]

This article introduces an algorithm for detecting glucose and silicon levels in solution. The research focuses on addressing the critical need for accurate and efficient glucose monitoring, particularly in the context of diabetic management. Understanding and monitoring silicon levels in the body is crucial due to its significant role in various physiological processes. Silicon, while often overshadowed by other minerals, plays a vital role in bone health, collagen formation, and connective tissue integrity. Moreover, recent research suggests its potential involvement in neurological health and the prevention of certain degenerative diseases. Investigating silicon levels becomes essential for a comprehensive understanding of its impact on overall health and well-being and paves the way for targeted interventions and personalized healthcare strategies. The approach presented in this paper is based on the integration of hyperspectral data and artificial intelligence techniques. The algorithm investigates the effectiveness of two distinct models utilizing SVMR and a perceptron independently. SVMR is employed to establish a robust regression model that maps input features to continuous glucose and silicon values. The study outlines the methodology, including feature selection, model training, and evaluation metrics. Experimental results demonstrate the algorithm's effectiveness at accurately predicting glucose and silicon concentrations and showcases its potential for real-world application in continuous glucose and silicon monitoring systems. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is a chronic metabolic condition characterized by high blood glucose levels owing to decreased insulin production or sensitivity. Current diagnostic approaches for gestational diabetes entail intrusive blood tests, which are painful and impractical for regular monitoring. Additionally, typical blood glucose monitoring systems are restricted in their measurement frequency and need finger pricks for blood samples. This research study focuses on the development of a non-invasive, real-time glucose monitoring method based on the detection of glucose in human tears and finger blood using mid-infrared (IR) spectroscopy. The proposed solution combines a fuzzy logic-based calibration mechanism with an IR sensor and Arduino controller. This calibration technique increases the accuracy of non-invasive glucose testing based on MID absorbance in fingertips and human tears. The data demonstrate that our device has high accuracy and reliability, with an error rate of less than 3%, according to the EGA. Out of 360 measurements, 97.5% fell into zone A, 2.2% into zone B, and 0.3% into zone C of the Clarke Error Grid. This suggests that our device can give clinically precise and acceptable estimates of blood glucose levels without inflicting any harm or discomfort on the user. [ABSTRACT FROM AUTHOR]

According to the age-old adage, while eyes are often considered the gateway to the soul, they might also provide insights into a more pragmatic aspect of our health: blood sugar levels. This potential breakthrough could be realized through the development of smart contact lenses (SCLs). Although contact lenses were first developed for eyesight correction, new uses have recently become available. In the near future, it might be possible to monitor a variety of ocular and systemic disorders using contact lens sensors. Within the realm of glaucoma, SCLs present a novel prospect, offering a potentially superior avenue compared to traditional management techniques. These lenses introduce the possibility of non-invasive and continuous monitoring of intraocular pressure (IOP) while also enabling the personalized administration of medication as and when needed. This convergence holds great promise for advancing glaucoma care. In this review, recent developments in SCLs, including their potential applications, such as IOP and glucose monitoring, are briefly discussed. [ABSTRACT FROM AUTHOR]

Neonatal diabetes mellitus is a rare genetic disease that affects 1 in 90,000 live births. The start of the disease is often before the baby is 6 months old, with rare cases of onset between 6 months and 1 year. It is characterized by low or absent insulin levels in the blood, leading to severe hyperglycemia in the patient, which requires temporary insulin therapy in around 50% of cases or permanent insulin therapy in other cases. Two major processes involved in diabetes mellitus are a deformed pancreas with altered insulin-secreting cell development and/or survival or faulty functioning of the existing pancreatic beta cell. We will discuss the cases of two preterm girls with neonatal diabetes mellitus in this research. In addition to reviewing the literature on the topic, we examined the different mutations, patient care, and clinical outcomes both before and after insulin treatment. [ABSTRACT FROM AUTHOR]

Sweat, a biofluid secreted naturally from the eccrine glands of the human body, is rich in several electrolytes, metabolites, biomolecules, and even xenobiotics that enter the body through other means. Recent studies indicate a high correlation between the analytes' concentrations in the sweat and the blood, opening up sweat as a medium for disease diagnosis and other general health monitoring applications. However, low concentration of analytes in sweat is a significant limitation, requiring high-performing sensors for this application. Electrochemical sensors, due to their high sensitivity, low cost, and miniaturization, play a crucial role in realizing the potential of sweat as a key sensing medium. MXenes, recently developed anisotropic two-dimensional atomic-layered nanomaterials composed of early transition metal carbides or nitrides, are currently being explored as a material of choice for electrochemical sensors. Their large surface area, tunable electrical properties, excellent mechanical strength, good dispersibility, and biocompatibility make them attractive for bio-electrochemical sensing platforms. This review presents the recent progress made in MXene-based bio-electrochemical sensors such as wearable, implantable, and microfluidic sensors and their applications in disease diagnosis and developing point-of-care sensing platforms. Finally, the paper discusses the challenges and limitations of MXenes as a material of choice in bio-electrochemical sensors and future perspectives on this exciting material for sweat-sensing applications. [ABSTRACT FROM AUTHOR]

Non-Invasive blood glucose monitoring using infrared (IR) light is considered to be a useful and reliable tool for measuring blood sugar levels during daily activities. IR-based glucose monitoring depends on the variant absorption levels of IR light waves by blood with high or low levels of glucose solution. This paper introduces a low-cost finger probe to measure glucose based on Arduino and embedding a Clarke error grid with fuzzy logic. An electronic blood glucose meter was designed and implemented in a non-invasive and painless manner based on an infrared sensor. The electrical signal expressing the level of glucose in the blood with a mathematical equation was used to calibrate and map the physical and electrical values. The final numerical value was validated with the Clarke error grid by implementing fuzzy logic (FL). The designed device was tested on 30 subjects with 15 diabetes subjects. The results show the high significance of results at points where the FL was able to determine an error range of less than 10% of measured glucose within the same range of the reference measurements. The proposed method of using FL with a Clarke error grid gives more confident and precise outputs in cases of this kind of portable device. [ABSTRACT FROM AUTHOR]

A diboronic acid anthracene-based fluorescent system for detecting blood glucose could be used for 180 days. However, there has not yet been a boronic acid immobilized electrode to selectively detect glucose in a signal-increased way. Considering malfunctions of sensors at high sugar levels, the electrochemical signal should be increased proportionally to the glucose concentration. Therefore, we synthesized a new diboronic acid derivative and fabricated the derivative-immobilized electrodes for the selective detection of glucose. We performed cyclic voltammetry and electrochemical impedance spectroscopy with an Fe(CN)63−/4− redox pair for detecting glucose in the range of 0–500 mg/dL. The analysis revealed increased electron-transfer kinetics such as increased peak current and decreased semicircle radius of Nyquist plots as the glucose concentration increased. The cyclic voltammetry and impedance spectroscopy showed that the linear detection range of glucose was 40 to 500 mg/dL with limits of detection of 31.2 mg/dL and 21.5 mg/dL, respectively. We applied the fabricated electrode to detect glucose in artificial sweat and obtained 90% of the performance of the electrodes in PBS. Cyclic voltammetry measurements of other sugars such as galactose, fructose, and mannitol also showed linear increased peak currents proportional to the concentrations of the tested sugars. However, the slopes of the sugars were lower than that of glucose, indicating selectivity for glucose. These results proved the newly synthesized diboronic acid is a promising synthetic receptor for developing a long-term usable electrochemical sensor system. [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIPs) have gained growing interest among researchers worldwide, due to their key features that make these materials interesting candidates for implementation as receptors into sensor applications. In fact, MIP-based glucose sensors could overcome the stability issues associated with the enzymes present in commercial glucose devices. Various reports describe the successful development of glucose MIPs and their coupling to a wide variety of transducers for creating sensors that are able to detect glucose in various matrices. In this review, we have summarized and critically evaluated the different production methods of glucose MIPs and the different transducer technologies used in MIP-based glucose sensors, and analyzed these from a commercial point of view. In this way, this review sets out to highlight the most promising approaches in MIP-based sensing in terms of both manufacturing methods and readout technologies employed. In doing so, we aim at delineating potential future approaches and identifying potential obstacles that the MIP-sensing field may encounter in an attempt to penetrate the commercial, analytical market. [ABSTRACT FROM AUTHOR]

This paper presents a low-noise potentiostat readout circuit with a chopper fully differential difference amplifier (FDDA) for glucose monitoring. Glucose monitoring is necessary for the early diagnosis of diabetes complications and for health management. Ammeter electrochemical sensors are widely used for glucose detection, and in general, a three-electrode structure of a reference electrode (RE), a counter electrode (CE), and a working electrode (WE) is implemented with a potentiostat structure. A low-noise characteristic of the readout circuit is essential for highly accurate glucose monitoring. The chopping technique can reduce low-frequency noises such as 1/f noise and can achieve the required low-noise characteristic. The proposed potentiostat readout circuit is based on a low-noise chopper FDDA with a class-AB output stage. The implementation of the chopper FDDA scheme of the potentiostat readout circuit can decrease the number of amplifiers in the control part of the potentiostat, with reduced power consumption and a wide dynamic output range. The negative feedback loop of the inverting amplifier scheme with the FDDA maintains the voltage between the WE and RE constants. The negative feedback loop tracks the reference voltage of the RE with an input voltage of the WE. The proposed potentiostat readout circuit is designed in the standard 0.18 µm CMOS process, and the simulated current consumption is 48.54 μA with a 1.8 V power supply. The simulated input-referred noise level was 8.53 pArms. [ABSTRACT FROM AUTHOR]

Background: Self-monitoring of blood glucose (SMBG) is of paramount relevance for type 2 diabetes mellitus (T2DM) patients. However, past evidence shows that there are physical and cognitive issues that might limit the usage of glucometers by T2DM patients aged 65 years and over. Objective: Our aim was to investigate the physical and cognitive issues related to the usage of glucometers by T2DM patients aged 65 years and over. Materials and Methods: The extant literature was analysed to define an original framework showing the logical nexus between physical and cognitive issues and quality of life. Then we collected evidence addressing the specific case of the Accu-Chek® Instant glucometer produced by Roche Diabetes Care GmbH, which implements new features claiming to improve usability. We conducted 30 interviews with T2DM patients aged 65 years and over, three interviews with senior nurses, and a focus group with three senior physicians and three senior nurses. Results: From the interviews, both patients and nurses declared that they were generally satisfied with the Accu-Chek® Instant glucometer's characteristics. In the focus group, the results were commented on and, in the light of some diverging answers, improvements have been set up for future implementation. Conclusions: Our study produces evidence and future suggestions about the usage of glucometers by type 2 diabetes patients aged 65 years and over. [ABSTRACT FROM AUTHOR]

Glucose measurement is a fundamental tool in the daily care of Diabetes Mellitus (DM) patients and healthcare professionals. While there is an established market for glucose sensors, the rising number of DM cases has promoted intensive research to provide accurate systems for glucose monitoring. Polyaniline (PAni) is a conductive polymer with a linear conjugated backbone with sequences of single C–C and double C=C bonds. This unique structure produces attractive features for the design of sensing systems such as conductivity, biocompatibility, environmental stability, tunable electrochemical properties, and antibacterial activity. PAni-based glucose sensors (PBGS) were actively developed in past years, using either enzymatic or non-enzymatic principles. In these devices, PAni played roles as a conductive material for electron transfer, biocompatible matrix for enzymatic immobilization, or sensitive layer for detection. In this review, we covered the development of PBGS from 2015 to the present, and it is not even exhaustive; it provides an overview of advances and achievements for enzymatic and non-enzymatic PBGB PBGS for self-monitoring and continuous blood glucose monitoring. Additionally, the limitations of PBGB PBGS to advance into robust and stable technology and the challenges associated with their implementation are presented and discussed. [ABSTRACT FROM AUTHOR]

Featured Application: The design is highly sensitive to various glucose concentrations in biological media and can be used for non-invasive monitoring of glucose concentrations. The article investigates the near-field probe of a special design to account for changes in glucose concentration. The probe is designed in such a way that it emits radiation in both directions from its plane. In this paper, it was proposed to modernize this design and consider the unidirectional emission of the probe in order to maximize the signal and reduce energy loss. We have done extensive research for both bidirectional and unidirectional probe designs. Numerical simulations and field experiments were carried out to determine different concentrations of glucose (0, 4, 5.3, 7.5 mmol/L). Numerical modeling of a unidirectional probe showed that the interaction of radiation generated by such a probe with a multilayer structure simulating a human hand showed a better result and high sensitivity compared to a bidirectional probe. Further, based on the simulation results, a phantom (physical model) of a human hand was recreated from layers with dielectric properties as close as possible to the properties of materials during simulation. The probe was constructed from a copper tube and matched both the geometric and physical parameters of the model. The experimental measurement was carried out using a vector network analyzer in the frequency range 2–10 GHz. The experimental measurement was carried out using a vector network analyzer in the frequency range 2–10 GHz for the unidirectional and bidirectional probes. Further, the results of the experiment were compared with the results of numerical simulation. According to the results of multiple experiments, it was found that the average deviation between the concentrations was 2 dB for a unidirectional probe and 0.4 dB for a bidirectional probe. Thus, the sensitivity of the unidirectional probe was 1.5 dB/(mmol/L) for the bidirectional one 0.3 dB/(mmol/L). Thus, the improved design of the near-field probe can be used to record glucose concentrations. [ABSTRACT FROM AUTHOR]

An affinity-viscometry-based micro-sensor probe for continuous glucose monitoring was investigated with respect to its suitability for bioprocesses. The sensor operates with glucose and dextran competing as binding partner for concanavalin A, while the viscosity of the assay scales with glucose concentration. Changes in viscosity are determined with a micro-electromechanical system (MEMS) in the measurement cavity of the sensor probe. The study aimed to elucidate the interactions between the assay and a typical phosphate buffered bacterial cultivation medium. It turned out that contact with the medium resulted in a significant long-lasting drift of the assay's viscosity at zero glucose concentration. Adding glucose to the medium lowers the drift by a factor of eight. The cglc values measured off-line with the glucose sensor for monitoring of a bacterial cultivation were similar to the measurements with an enzymatic assay with a difference of less than ±0.15 g·L-1. We propose that lectin agglomeration, the electro-viscous effect, and constitutional changes of concanavalin A due to exchanges of the incorporated metal ions may account for the observed viscosity increase. The study has demonstrated the potential of the MEMS sensor to determine sensitive viscosity changes within very small sample volumes, which could be of interest for various biotechnological applications. [ABSTRACT FROM AUTHOR]

Diabetes is a rapidly growing disease that can be monitored at an individual level by controlling the blood glucose level, hence minimizing the negative impact of the disease. Significant research efforts have been focused on the design of novel and improved technologies to overcome the limitations of existing glucose analysis methods. In this context, nanotechnology has enabled the diagnosis at the single cell and molecular level with the possibility of incorporation in advanced molecular diagnostic biochips. Recent years have witnessed the exploration and synthesis of various types of nanomaterials with enzyme-like properties, with their subsequent integration into the design of biomimetic optical sensors for glucose monitoring. This review paper will provide insights on the type, nature and synthesis of different biomimetic nanomaterials. Moreover, recent developments in the integration of these nanomaterials for optical glucose biosensing will be highlighted, with a final discussion on the challenges that must be addressed for successful implementation of these nano-devices in the clinical applications is presented. [ABSTRACT FROM AUTHOR]

The anxiety and pain associated with frequent finger pricking has always been troublesome for diabetics measuring blood glucose (BG) in their daily lives. For this reason, a reliable glucose monitoring system that allows noninvasive measurements is highly desirable. Our main objective is to develop a biosensor that can detect low-level glucose in saliva (physiological range 0.5-20 mg/dL). Salivary glucose (SG) sensors were built using a layer-by-layer self-assembly of single-walled carbon nanotubes, chitosan, gold nanoparticles, and glucose oxidase onto a screen-printed platinum electrode. An electrochemical method was utilized for the quantitative detection of glucose in both buffer solution and saliva samples. A standard spectrophotometric technique was used as a reference method to validate the glucose content of each sample. The disposable glucose sensors have a detection limit of 0.41 mg/dL, a sensitivity of 0.24 µA⋅s⋅dL⋅mg-1, a linear range of 0.5-20 mg/dL in buffer solution, and a response time of 30 s. A study of 10 healthy subjects was conducted, and SG levels between 1.1 to 10.1 mg/dL were successfully detected. The results revealed that the noninvasive SG monitoring could be an alternative for diabetes self-management at home. This paper is not intended to replace regular BG tests, but to study SG itself as an indicator for the quality of diabetes care. It can potentially help patients control and monitor their health conditions, enabling them to comply with prescribed treatments for diabetes. [ABSTRACT FROM AUTHOR]

Proof-of-concept studies that display the potential of using a glucose-sensitive hydrogel as a continuous glucose sensor are presented. The swelling ratio, porosity, and diffusivity of the hydrogel increased with glucose concentration. In glucose solutions of 50, 100, 200, and 300 mg/dL, the hydrogel swelling ratios were 4.9, 12.3, 15.9, and 21.7, respectively, and the swelling was reversible. The impedance across the hydrogel depended solely on the thickness and had an average increase of 47 Ω/mm. The hydrogels exposed to a hyperglycemic solution were more porous than the hydrogels exposed to a normal glycemic solution. The diffusivity of 390 Da MW fluorescein isothiocyanate in hydrogels exposed to normal and hyperglycemic solutions was examined using fluorescence recovery after photobleaching and was found to be 9.3 × 10-14 and 41.4 × 10-14 m2/s, respectively, compared to 6.2 × 10-10 m2/s in glucose solution. There was no significant difference between the permeability of hydrogels in normal and hyperglycemic glucose solutions with averages being 5.26 × 10-17 m2 and 5.80 × 10-17 m2, respectively, which resembles 2-4% agarose gels. A prototype design is presented for continuous intravascular glucose monitoring by attaching a glucose sensor to an FDA-approved stent. [ABSTRACT FROM AUTHOR]

Fourier transformation infrared (FT-IR) spectroscopy has been used to measure glucose concentrations in different matrices. The accuracy of the FT-IR technique does not meet the requirements of medical applications, so we have developed a new, efficient and precise method based on attenuated total reflectance coupled with wavelet transformation (ATR-WT-IR). One thousand interferograms, divided into training- and testing-sets, have been recorded from four glucose concentrations using an ATR-IR unit. Signals were subjected to (WT) and neural network (NN) study in order to design correlation algorithm. The Pearson's Correlation Coefficient (PCC) obtained by judging the predicted- against the real-concentrations was 0.9954, with a mean square error of 8.4e-005. The proposed ATRWT-IR method shows efficiency in glucose prediction and could possibly to be integrated into a non-invasive monitoring technique. [ABSTRACT FROM AUTHOR]

(1) Background: The use of smart devices to better manage diabetes has increased significantly in recent years. These technologies have been introduced in order to make life easier for patients with diabetes by allowing better control of the stability of blood sugar levels and anticipating the occurrence of dangerous events (hypo/hyperglycemia), etc. That being said, the main objectives of the self-management of diabetes is to improve the lifestyle and life quality of patients with diabetes; (2) Methods: We performed a systematic review based on articles that focus on the use of smart devices for the monitoring and better management of diabetes. The search was focused on keywords related to the topic, such as "Diabetes", "Technology", "Self-management", "Artificial Intelligence", etc. This was performed using databases, such as Scopus, Google Scholar, and PubMed; (3) Results: A total of 89 studies, published between 2011 and 2021, were included. The majority of the selected research aims to solve a diabetes management problem (e.g., blood glucose prediction, early detection of risk events, and the automatic adjustment of insulin doses, etc.). In these studies, wearable devices were used in combination with artificial intelligence (AI) techniques; (4) Conclusions: Wearable devices have attracted a great deal of scientific interest in the field of healthcare for people with chronic conditions, such as diabetes. They are capable of assisting in the management of diabetes, as well as preventing complications associated with this condition. Furthermore, the usage of these devices has improved illness management and quality of life. [ABSTRACT FROM AUTHOR]

In recent years, wearable contact lenses for medical applications have attracted significant attention, as they enable continuous real-time recording of physiological information via active and noninvasive measurements. These devices play a vital role in continuous monitoring of intraocular pressure (IOP), noninvasive glucose monitoring in diabetes patients, drug delivery for the treatment of ocular illnesses, and colorblindness treatment. In specific, this class of medical devices is rapidly advancing in the area of drug loading and ocular drug release through incorporation of electrospun fibers. The electrospun fiber matrices offer a high surface area, controlled morphology, wettability, biocompatibility, and tunable porosity, which are highly desirable for controlled drug release. This article provides an overview of the advances of contact lens devices in medical applications with a focus on four main applications of these soft wearable devices: (i) IOP measurement and monitoring, (ii) glucose detection, (iii) ocular drug delivery, and (iv) colorblindness treatment. For each category and application, significant challenges and shortcomings of the current devices are thoroughly discussed, and new areas of opportunity are suggested. We also emphasize the role of electrospun fibers, their fabrication methods along with their characteristics, and the integration of diverse fiber types within the structure of the wearable contact lenses for efficient drug loading, in addition to controlled and sustained drug release. This review article also presents relevant statistics on the evolution of medical contact lenses over the last two decades, their strengths, and the future avenues for making the essential transition from clinical trials to real-world applications. [ABSTRACT FROM AUTHOR]

This paper describes the design methodology and calibration technique for a low-power digital pulse width modulation demodulator to enhance its robustness against the process, voltage, and temperature variations in different process corners, in addition to intra-die variability, which makes it a very good choice for implantable monitoring sensors. Furthermore, the core of the proposed demodulator is fully digital. Thus, along with the proposed design methodology, the proposed demodulator can be simply redesigned in advanced subnanometer CMOS technologies without much difficulty as compared to analog demodulators. The proposed demodulator consists of an envelope detector, a digitizer, a ring oscillator, and a data detector with digital calibration. All the proposed circuits are designed and simulated in the standard 1P9M TSMC's 40 nm CMOS technology. Simulation results have shown that the circuit is capable of demodulating and recovering data from an input signal with a carrier frequency of 13.56 MHz and a data rate of 143 kB/s with an average power consumption of 5.62 μ W. [ABSTRACT FROM AUTHOR]

The use of microwave technology is currently under investigation for non-invasive estimation of glycemia in patients with diabetes. Due to their construction, metamaterial (MTM)-based sensors have the potential to provide higher sensitivity of the phase shift of the S21 parameter ( ∠ S 21 ) to changes in glucose concentration compared to standard microstrip transmission line (MSTL)-based sensors. In this study, a MSTL sensor and three MTM sensors with 5, 7, and 9 MTM unit cells are exposed to liquid phantoms with different dielectric properties mimicking a change in blood glucose concentration from 0 to 14 mmol/L. Numerical models were created for the individual experiments, and the calculated S-parameters show good agreement with experimental results, expressed by the maximum relative error of 8.89% and 0.96% at a frequency of 1.99 GHz for MSTL and MTM sensor with nine unit cells, respectively. MTM sensors with an increasing number of cells show higher sensitivity of 0.62° per mmol/L and unit cell to blood glucose concentration as measured by changes in ∠ S 21 . In accordance with the numerical simulations, the MTM sensor with nine unit cells showed the highest sensitivity of the sensors proposed by us, with an average of 3.66° per mmol/L at a frequency of 1.99 GHz, compared to only 0.48° per mmol/L for the MSTL sensor. The multi-cell MTM sensor has the potential to proceed with evaluation of human blood samples. [ABSTRACT FROM AUTHOR]

Hyperglycemia is associated with adverse outcomes after coronary artery bypass grafting (CABG). While there is a consensus that blood glucose control may benefit patients undergoing CABG, the role of biomarkers, optimal method, and duration of such monitoring are still unclear. The aim of this study is to define the efficacy of a continuous glucose monitoring system (CGMS) and link it to pro-inflammatory biomarkers while on insulin pump therapy in diabetic patients undergoing CABG. We prospectively assessed CGMS for 72 h in 105 patients including 52 diabetics undergoing isolated CABG. In diabetics, CGMS was connected to an insulin pump for precise glucose control. On top of conventional biomarkers (HbA1C, lipid profile), high sensitive C-reactive protein (hs-CRP), Regulated upon Activation Normal T cell Expressed and presumably Secreted (RANTES), and leptin levels were collected before surgery, 1 h, 12 h, 7 days, and at 1 year after CABG. Overall, CGMS revealed high glucose independently from underlying diabetes during first 48 h following CABG but was higher (p < 0.05) in diabetics. The insulin pump improved glycemic control over early follow-up (72 h) post-CABG. There were no hypoglycemic episodes in patients on insulin pump therapy and those receiving bolus insulin therapy. We revealed a lower rate of postpericardiotomy syndrome (PCTS) in patients on insulin pump therapy compared to patients prescribed bolus insulin therapy in the early postoperative period (p = 0.03). Hs-CRP and RANTES levels were lower in patients with T2DM on insulin pump therapy compared to patients prescribed bolus insulin therapy in the early postoperative period (p < 0.05). It is most likely due to the fact that insulin pump therapy decreases systemic inflammatory response. Further controlled trials should assess whether CGMS improves outcomes after cardiac surgery. [ABSTRACT FROM AUTHOR]

We present fluorescent Janus hydrogel microbeads for continuous glucose sensing with pH calibration. The Janus hydrogel microbeads, that consist of fluorescent glucose and pH sensors, were fabricated with a UV-assisted centrifugal microfluidic device. The microbead can calibrate the pH values of its surroundings and enables accurate measurements of glucose within various pH conditions. As a proof of concept, we succeeded in obtaining the accurate value of glucose concentration in a body-fluid-like sample solution. We believe that our fluorescent microbeads, with pH calibration capability, could be applied to fully implantable sensors for continuous glucose monitoring. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a chronic metabolic disorder, being globally one of the most deadly diseases. This disease requires continually monitoring of the body's glucose levels. There are different types of sensors for measuring glucose, most of them invasive to the patient. Fiber optic sensors have been proven to have advantages compared to conventional sensors and they have great potential for various applications, especially in the biomedical area. Compared to other sensors, they are smaller, easy to handle, mostly non-invasive, thus leading to a lower risk of infection, high precision, well correlated and inexpensive. The objective of this review article is to compare different types of fiber optic sensors made with different experimental techniques applied to biomedicine, especially for glucose sensing. Observations are made on the way of elaboration, as well as the advantages and disadvantages that each one could have in real applications. [ABSTRACT FROM AUTHOR]

Diabetes patients suffer from abnormal blood glucose levels, which can cause diverse health disorders that affect their kidneys, heart and vision. Due to these conditions, diabetes patients have traditionally checked blood glucose levels through Self-Monitoring of Blood Glucose (SMBG) techniques, like pricking their fingers multiple times per day. Such techniques involve a number of drawbacks that can be solved by using a device called Continuous Glucose Monitor (CGM), which can measure blood glucose levels continuously throughout the day without having to prick the patient when carrying out every measurement. This article details the design and implementation of a system that enhances commercial CGMs by adding Internet of Things (IoT) capabilities to them that allow for monitoring patients remotely and, thus, warning them about potentially dangerous situations. The proposed system makes use of smartphones to collect blood glucose values from CGMs and then sends them either to a remote cloud or to distributed fog computing nodes. Moreover, in order to exchange reliable, trustworthy and cybersecure data with medical scientists, doctors and caretakers, the system includes the deployment of a decentralized storage system that receives, processes and stores the collected data. Furthermore, in order to motivate users to add new data to the system, an incentive system based on a digital cryptocurrency named GlucoCoin was devised. Such a system makes use of a blockchain that is able to execute smart contracts in order to automate CGM sensor purchases or to reward the users that contribute to the system by providing their own data. Thanks to all the previously mentioned technologies, the proposed system enables patient data crowdsourcing and the development of novel mobile health (mHealth) applications for diagnosing, monitoring, studying and taking public health actions that can help to advance in the control of the disease and raise global awareness on the increasing prevalence of diabetes. [ABSTRACT FROM AUTHOR]

The aim of this review was to investigate existing guidelines and scientific evidence on determining insulin dosage in people with type 1 and type 2 diabetes, and in particular to check whether the prandial insulin dose should be calculated based on glycemia or the meal composition, including the carbohydrates, protein and fat content in a meal. By exploring the effect of the meal composition on postprandial glycemia we demonstrated that several factors may influence the increase in glycemia after the meal, which creates significant practical difficulties in determining the appropriate prandial insulin dose. Then we reviewed effects of the existing insulin therapy regimens on glycemic control. We demonstrated that in most existing algorithms aimed at calculating prandial insulin doses in type 1 diabetes only carbohydrates are counted, whereas in type 2 diabetes the meal content is often not taken into consideration. We conclude that prandial insulin doses in treatment of people with diabetes should take into account the pre-meal glycemia as well as the size and composition of meals. However, there are still open questions regarding the optimal way to adjust a prandial insulin dose to a meal and the possible benefits for people with type 1 and type 2 diabetes if particular parameters of the meal are taken into account while calculating the prandial insulin dose. The answers to these questions may vary depending on the type of diabetes. [ABSTRACT FROM AUTHOR]

Digital technologies are gaining an important role in the management of patients with diabetes. We assessed clinical outcomes and user satisfaction of incorporating a digital diabetes care system in diabetes clinics of a developing country. The system integrated a wireless blood glucose monitor that communicates data to any smartphone utilizing a patented acoustic data transfer method, a mobile-app, and cloud-based software that stores, analyzes, and presents data. Five hospital endocrinology clinics in Vietnam sequentially recruited all patients willing to join the study, providing they had a smartphone and access to internet connectivity. Face-to-face visits were conducted at baseline and at 12 weeks, with monthly digital visits scheduled in the interim and additional digital visits performed as needed. HbA1c levels were measured at baseline and at 12 weeks (±20 days). The study included 300 patients of whom 279 completed the evaluation. Average glucose levels declined from 170.4 ± 64.6 mg/dL in the first 2 weeks to 150.8 ± 53.2 mg/dL in the last 2 weeks ( n = 221; p < 0.001). HbA1c levels at baseline and 12 weeks declined from 8.3% ± 1.9% to 7.6% ± 1.3% ( n = 126; p < 0.001). The digital solution was broadly accepted by both patients and healthcare professionals and improved glycemic outcomes. The durability, scalability, and cost-effectiveness of this approach merits further study.

Diabetes has become a serious health concern. The use and popularization of blood glucose measurement devices have led to a tremendous increase on health for diabetics. Tracking and maintaining traceability between glucose measurements, insulin doses and carbohydrate intake can provide useful information to physicians, health professionals, and patients. This paper presents an information system, called GLUMIS (GLUcose Management Information System), aimed to support diabetes management activities. It is made of two modules, one for glucose prediction and one for data visualization and a reasoner to aid users in their treatment. Through integration with glucose measurement devices, it is possible to collect historical data on the treatment. In addition, the integration with a tool called the REALI System allows GLUMIS to also process data on insulin doses and eating habits. Quantitative and qualitative data were collected through an experimental case study involving 10 participants. It was able to demonstrate that the GLUMIS system is feasible. It was able to discover rules for predicting future values of blood glucose by processing the past history of measurements. Then, it presented reports that can help diabetics choose the amount of insulin they should take and the amount of carbohydrate they should consume during the day. Rules found by using one patient's measurements were analyzed by a specialist that found three of them to be useful for improving the patient's treatment. One such rule was "if glucose before breakfast ∈ [ 47 , 89 ] , then glucose at afternoon break in [ 160 , 306 ] ". The results obtained through the experimental study and other verifications associated with the algorithm created had a double objective. It was possible to show that participants, through a questionnaire, viewed the visualizations as easy, or very easy, to understand. The secondary objective showed that the innovative algorithm applied in the GLUMIS system allows the decision maker to have much more precision and less loss of information than in algorithms that require the data to be discretized. [ABSTRACT FROM AUTHOR]

Diabetes has become a chronic metabolic disorder, and the growing diabetes population makes medical care more important. We investigated using a portable and noninvasive contact lens as an ideal sensor for diabetes patients whose tear fluid contains glucose. The key feature is the reversible covalent interaction between boronic acid and glucose, which can provide a noninvasive glucose sensor for diabetes patients. We present a phenylboronic acid (PBA)-based HEMA contact lens that exhibits a reversible swelling/shrinking effect to change its thickness. The difference in thickness can be detected in a picture taken with a smartphone and analyzed using software. Our novel technique offers the following capabilities: (i) non-enzymatic and continuous glucose detection with the contact lens; (ii) no need for an embedded circuit and power source for the glucose sensor; and (iii) the use of a smartphone to detect the change in thickness of the contact lens with no need for additional photo-sensors. This technique is promising for a noninvasive measurement of the glucose level and simple implementation of glucose sensing with a smartphone. [ABSTRACT FROM AUTHOR]