Recreating the size-dependent reabsorption function of proximal convoluted tubule towards artificial kidney applications: Structural analysis and computational study.

Human kidneys tend to be affected adversely and fail to function more often than any other organ in the body because of diet, heredity, and lifestyle of a person. Dialysis is the technique presently in use for replacing the failed kidney function but it is packed with painfulness, bulkiness, and is costly also. There is a growing need for development of an artificial kidney that eradicates the problems associated with dialysis. This article proposes a structure that mimics the most important aspect of the human kidney: the size-dependent reabsorption of endothelial cells in the proximal convoluted tubule (PCT). The proposed structure consists of transporting channels connecting blood tubules surrounded on both sides of a main tubule. Geometries of the channels are analyzed for optimum flow by varying angles with respect to the main tubule. The analytical formulae have been developed by considering proper boundary conditions governing the flow in the structure, which makes the model as robust, concise, and realistic as the actual PCT. The mathematical model is validated against the benchmark FEM tool COMSOL Multiphysics and the results seem to be satisfactory. This article concludes, that slant channels possess a considerably higher average flow velocity of 5.39 × 10-5  m/s (≈52% reabsorption rate) than straight channels with 4.77 × 10-5  m/s (≈46% reabsorption rate) which is closer to the actual PCT reabsorption rate of 60%. The proposed model is first of its kind in nature among the reported works which creates and exhibits simulation environment of PCT reabsorption function supported by mathematical formulation and also can be useful to study and develop artificial kidney in near future.

Artificial intelligence powered glucose monitoring and controlling system: Pumping module.

BACKGROUND: Diabetes, a globally escalating health concern, necessitates innovative solutions for efficient detection and management. Blood glucose control is an essential aspect of managing diabetes and finding the most effective ways to control it. The latest findings suggest that a basal insulin administration rate and a single, high-concentration injection before a meal may not be sufficient to maintain healthy blood glucose levels. While the basal insulin rate treatment can stabilize blood glucose levels over the long term, it may not be enough to bring the levels below the post-meal limit after 60 min. The short-term impacts of meals can be greatly reduced by high-concentration injections, which can help stabilize blood glucose levels. Unfortunately, they cannot provide long-term stability to satisfy the post-meal or pre-meal restrictions. However, proportional-integral-derivative (PID) control with basal dose maintains the blood glucose levels within the range for a longer period. AIM: To develop a closed-loop electronic system to pump required insulin into the patient's body automatically in synchronization with glucose sensor readings. METHODS: The proposed system integrates a glucose sensor, decision unit, and pumping module to specifically address the pumping of insulin and enhance system effectiveness. Serving as the intelligence hub, the decision unit analyzes data from the glucose sensor to determine the optimal insulin dosage, guided by a pre-existing glucose and insulin level table. The artificial intelligence detection block processes this information, providing decision instructions to the pumping module. Equipped with communication antennas, the glucose sensor and micropump operate in a feedback loop, creating a closed-loop system that eliminates the need for manual intervention. RESULTS: The incorporation of a PID controller to assess and regulate blood glucose and insulin levels in individuals with diabetes introduces a sophisticated and dynamic element to diabetes management. The simulation not only allows visualization of how the body responds to different inputs but also offers a valuable tool for predicting and testing the effects of various interventions over time. The PID controller's role in adjusting insulin dosage based on the discrepancy between desired setpoints and actual measurements showcases a proactive strategy for maintaining blood glucose levels within a healthy range. This dynamic feedback loop not only delays the onset of steady-state conditions but also effectively counteracts post-meal spikes in blood glucose. CONCLUSION: The WiFi-controlled voltage controller and the PID controller simulation collectively underscore the ongoing efforts to enhance efficiency, safety, and personalized care within the realm of diabetes management. These technological advancements not only contribute to the optimization of insulin delivery systems but also have the potential to reshape our understanding of glucose and insulin dynamics, fostering a new era of precision medicine in the treatment of diabetes.

Design and Modeling of Bioreactor Utilizing Electrophoresis and Di-Electrophoresis Techniques for Regenerating Reabsorption Function of Human Kidney PCT in Microfluidics Environment.

The need for innovation in medical device technology is immense; especially to replace dialysis techniques the necessity is extremely high. Available techniques that promised to replace dialysis have not yet geared up to the marketization level. The utilization of live kidney cells makes these devices costly, delicate, and unreliable. This paper aims to design a bioreactor to mimic the reabsorption function of the kidney that is fully artificial and highly controllable, which can be one step forward to the emerging Kidney-on-Chip (KOC) technology. The additional benefit of the proposed design is that it utilizes size-dependent reabsorption along with charge-dependent reabsorption phenomena to make it more compatible with human kidney function. The electrophoresis (EP), and di-electrophoresis (DEP) techniques are utilized to mimic the reabsorption function in this report. The structure utilized in the present design exactly replicates the proximal convoluted tubule (PCT) dimensions and functions as well. The whole setup is implemented in the COMSOL Multiphysics FEM benchmark tool for simulation, and analysis with appropriate boundary conditions. The device when excited by an electric field, Electrophoresis has produced a maximum velocity of 1.07 m/s for DC excitation and di-electrophoresis has produced a maximum flow velocity of 1.23 m/s, where both the offset voltages are the same (0.7 V). The flow velocity obtained utilizing both EP and DEP produced a reabsorption rate of 50-58% depending on the voltage applied and dimensions considered which is close to 60% reabsorption rate of the normal human kidney PCT. In accordance with the outcomes produced, the di-electrophoresis technique proved to be more efficient in realizing bioreactor as compared to electrophoresis. The novelty of the present work lies in the creation of a simulation environment, rigorous analysis, and optimization of the bioreactor supported by compact mathematical model.

A comprehensive review on advancements in tissue engineering and microfluidics toward kidney-on-chip.

This review provides a detailed literature survey on microfluidics and its road map toward kidney-on-chip technology. The whole review has been tailored with a clear description of crucial milestones in regenerative medicine, such as bioengineering, tissue engineering, microfluidics, microfluidic applications in biomedical engineering, capabilities of microfluidics in biomimetics, organ-on-chip, kidney-on-chip for disease modeling, drug toxicity, and implantable devices. This paper also presents future scope for research in the bio-microfluidics domain and biomimetics domain.