Artificial Organs

Chronic Kidney Disease (CKD) is an increasing concern in Tanzania, as well as a significant concern worldwide, due to the fact that transplantations rely on living donors. While living kidney donation may be ethically acceptable, there are many concerns with regard to the harm caused to living kidney donors, the potential for coercion of these donors, and the lack of equitable access to this form of donation. The purpose of this paper is to demonstrate that deceased kidney donations are the morally superior alternative to live kidney donations. The rationale behind this argument is based on a moral principle known as Utilitarianism. That is to say, the primary goal of all decisions made with regard to transplantation should be to maximize benefits to the largest number of people. In addition to the moral principle of utilitarianism, this paper will also draw upon three additional moral principles of Non-Maleficence, Justice, and Respect for Autonomy to demonstrate how deceased donor kidney transplantation can avoid the harm associated with live kidney donation, increase the number of available kidneys for transplantation, and create a system whereby kidneys are allocated fairly.

Globally, organ donation and transplantation save and improve millions of lives yearly. Despite the acclaim, various medical, ethical, moral and regulatory issues have trailed the procedure from the beginning until the present. This paper appraises Nigeria's efforts to discharge its duty to provide an effective legal and regulatory framework for organ donation and transplantation in Nigeria. The international regulations, as well as the regulatory needs thrown up by the challenges of the field, serve as the standards against which Nigeria's efforts are measured. This research utilises the doctrinal legal research methodology. This involves the systematic examination of primary and secondary legal sources to describe, analyse, and critique the existing state of the law and to propose normative reforms. Primary sources examined include the Constitution of the Federal Republic of Nigeria 1999, health-related legislation from Nigeria, the United States of America, the United Kingdom and South Africa, as well as relevant international instruments. Secondary sources consulted include journal articles, reports of civil society organisations, and the interpretive documents on international human rights instruments. The paper finds that while Nigerian law complies in some respects with the international regulations, there is a need to inculcate regulation on some omitted issues, strengthen the provisions on others, and provide more detailed rules on some other problematic subjects. It also finds that the government has habitually demonstrated a lackadaisical attitude with regard to providing or implementing the requisite legal framework on health sector issues.

The uremic syndrome is a complex mixture of organ dysfunctions, which is attributed to the retention of a myriad of compounds that under normal condition are excreted by the healthy kidneys (uremic toxins). In the area of identification and characterization of uremic toxins and in the knowledge of their pathophysiologic importance, major steps forward have been made during recent years. The present article is a review of several of these steps, especially in the area of information about the compounds that could play a role in the development of cardiovascular complications. It is written by those members of the Uremic Toxins Group, which has been created by the European Society for Artificial Organs (ESAO). Each of the 16 authors has written a state of the art in his/her major area of interest.

obtained a PhD degree in stem cell biology at King's College London under the supervision of Prof. Paul Sharpe who is the lead of the team that had developed a pioneering technology for creating teeth by using stem cells. Dr. Mohamed also worked for the University of Warwick for the last 6 years as a director for 2 dental masters programmes and as the lead for postgraduate dental research at Warwick Medical School. Dr. Mohamed's research profile includes clinical, medical and laboratory research as well as systematic reviewing and metaanalyses with publications and participations in national and international journals and conferences.

Mechanical circulatory support devices have become an important treatment tool for severe acute and chronic heart failure, since heart transplantation cannot meet the demands because of a lack of available donor organs. Since implantation of the first ventricular assist device a constant development of the suitability of these devices has been made. This review will introduce different generations of left ventricular assist devices (LVAD) and elaborate on clinical indications, risk stratification and current literature.

their insight and feedback during my research. My heartfelt thanks go to Kristin Sverrisdottir for her complete support throughout all these years. Without your friendship this journey of mine in abroad would not have been this awesome and pleasant. You always stood beside me. The time we spent together is invaluable to me. A special thanks to Rebecca Gold for editing my writing on such short notices. I really appreciate your hard work. I am also thankful to the whole senior design group of 2015-16 and Anthony Khoury and Jake Tibbets for their diligent work to make this research successful. I wish you all the best of luck through your endeavors. I am so grateful to my family, especially my parents and my late grandmother "Priti Kana das" for my upbringing and for being there for me during all my hard times. Last but not the least I would like to thanks all my friends especially Bhushan, Sultan and Alex to make my graduate school life awesome.

Purpose: The Boston keratoprosthesis (KPro) is the most commonly used KPro worldwide. There are limited data on the outcomes when irradiated corneas are used as KPro carriers. We report a retrospective analysis of corneal transplantations performed in a regular surgical mission setting in Beirut, Lebanon, using the Boston KPro type 1 and gamma-irradiated carrier corneas, and we describe visual outcomes, complications, and retention percentage. We conducted a retrospective analysis of 17 consecutive eyes from 16 patients who underwent Boston KPro type 1 implantation at the Beirut Eye Specialist Hospital between December 2010 and July 2012. Patient medical records were reviewed for preoperative, intraoperative, and postoperative details. Results: Postoperatively, 9 (52.9%), 5 (29.4%), and 2 (11.7%) eyes had a corrected visual acuity of 20/400 or better, 20/100 or better, and 20/40 or better, respectively, at the most recent follow-up visit. A total of 16 eyes (94.1%) improved in corrected visual acuity over the course of follow-up. Overall, 13 eyes (76.4%) developed at least 1 complication after surgery. Retroprosthetic membrane formation was the most common complication, occurring in 10 eyes (58.8%). Neither infectious keratitis nor corneal stromal necrosis was noted during the follow-up period. The retention percentage was 94.1%. The visual acuity outcomes, incidence of complications, and retention percentage of the KPro using gamma-irradiated carrier corneas are comparable with the outcomes of KPro implantation reported in the literature using fresh grafts as carriers. KPro with irradiated corneal carrier grafts seems to be an effective option to increase the supply of transplantation suitable corneas in remote areas, where fresh corneal grafts may be scarce.

Cryopreserved total skin allografts are a new therapeutic alternative for the management of complex wounds. Their properties allow them to be classified as a temporary coverage for some patients and as definitive in others. And they can be an alternative option to the use of dermal regeneration templates.

This research aims to design and process a low elastic modulus near-b Tie30Nbe3Ag at% (TNA) alloy with enhanced corrosion and antibacterial characteristics for bioimplant uses. Powder metallurgy was used to process the TNA alloy, which was designed via a combined approach of molybdenum equivalency and the d-electron alloy design method. The alloy powder samples were sintered at 1100, 1200, and 1300 C. XRD and SEM were utilized to examine the phases and microstructure. The modulus of elasticity and microhardness were evaluated using microindentation. The in vitro corrosion properties were also examined in artificial body fluid medium. The results showed that TNA alloy was predominantly composed of b-Ti, with trace amounts of a-Ti, a'', and Ti 2 Ag phases. The density and microhardness were increased by increasing the sintering temperature, and the sample sintered at 1300 C exhibited a homogeneous microstructure with 89.7% densification. The modulus of elasticity of the designed TNA alloys lowered by (28.5e43) % and (24e38) % compared to Ti6Al4V alloy and CP-Ti, respectively, which potentially contributes to a decrease in the stress-shielding effect. The in vitro corrosion results indicated that the resistance to corrosion of the TNA alloy improved with increasing sintering temperature as evidenced by an increase in charge transfer resistance, noble corrosion potential, and passive current density. Furthermore, the TNA alloy also demonstrated a higher antibacterial capability (82.9%) compared to Ti6Al4V alloy. The designed TNA alloy with low elastic modulus exhibits higher in vitro corrosion resistance and antibacterial properties making it a potential bioimplant material.

Use of extracorporeal membrane oxygenation (ECMO) is expanding, however it is still associated with significant morbidity and mortality. Activation of inflammatory and innate immune responses and hemostatic alterations contribute to complications. Hyperoxia may play a role in exacerbating these responses. Nine ex vivo ECMO circuits were tested using fresh healthy human whole blood, with two oxygen levels: 21% inspired fraction of oxygen (FiO 2 ; mild hyperoxia; n=5) and 100% FiO 2 (severe hyperoxia; n=4). Serial blood samples were taken for analysis of platelet aggregometry, leukocyte activation, inflammatory and oxidative stress markers. ECMO resulted in reduced adenosine diphosphate-(p<0.05) and thrombin receptor activating peptide-induced (p<0.05) platelet aggregation, as well as increasing levels of the neutrophil activation marker, neutrophil elastase (p=0.013). Additionally, levels of the inflammatory chemokine interleukin-8 were elevated (p<0.05) and the activity of superoxide dismutase, a marker of oxidative stress, was increased (p=0.002). Hyperoxia did not augment these responses, with no significant differences detected between mild and severe hyperoxia. Our ex vivo model of ECMO revealed that the circuit itself triggers a pro-inflammatory and oxidative stress response however exposure to supra-physiologic oxygen does not amplify that response. Extended-duration studies and inclusion of an endothelial component could be beneficial in characterizing longer-term changes.

Skin allografts are essential in managing complex wounds, yet their availability is limited by low post-mortem donation rates. Skin harvested during body contouring surgeries offers a novel and sustainable source to expand tissue supply. We conducted a retrospective descriptive study at the Tarapacá Skin and Tissue Bank from January 2022 to December 2024. All donations from body contouring surgeries were processed as cryopreserved total skin allografts following national tissue banking standards. Variables included donor demographics, harvested area, units produced, microbiological results, and discard rates. To describe clinical performance, we present our group's initial clinical series of treated patients. From 248 living donors (mean age 41.3 years), 81 293 cm 2 of skin generated 2050 units. The discard rate was 27%, mainly due to a storage failure and isolated microbial contamination. Clinically, all patients achieved complete initial graft take, followed by gradual necrotic eschar formation at an average of 21 days. Eschar removal revealed vital tissue firmly adhered to the recipient bed, rich in fibroblasts and neovascular structures. Subsequent management included either escharectomy with split-thickness autografting over the neodermis, or spontaneous eschar lysis and skin regeneration, with the graft functioning as a dermal regenerator. This model increases tissue availability while providing allografts with both coverage and dermal regenerative properties. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Background: To date, cell cultures have been created either on 2-dimensional (2D) polystyrene surfaces or in 3-dimensional (3D) systems, which do not offer a controlled chemical composition, and which lack the soft environment encountered in vivo and the chemical stimuli that promote cell proliferation and allow complex cellular behavior. In this study, pectin-based hydrogels were developed and are proposed as versatile cell culture systems. Methods: Pectin-based hydrogels were produced by internally crosslinking pectin with calcium carbonate at different initial pH, aiming to control crosslinking kinetics and degree. Additionally, glucose and glutamine were added as additives, and their effects on the viscoelastic properties of the hydrogels and on cell viability were investigated. Results: Pectin hydrogels showed in high cell viability and shear-thinning behavior. Independently of hydrogel composition, an initial swelling was observed, followed by a low percentage of weight variation and a steady-state stage. The addition of glucose and glutamine to pectin-based hydrogels rendered higher cell viability up to 90%-98% after 1 hour of incubation, and these hydrogels were maintained for up to 7 days of culture, yet no effect on viscoelastic properties was detected. Conclusions: Pectin-based hydrogels that offer tunable composition were developed successfully. They are envisioned as synthetic extracellular matrix (ECM) either to study complex cellular behaviors or to be applied as tissue engineering substitutes.

BACKGROUND.In patients with end-stage renal disease (ESRD), monocytes undergo accelerated in vitro apoptosis. The apoptosis could be induced by the cytokines such as tumor necrosis factor-α (TNF-α). The aim of this study was to evaluate the effect of both uremic toxin and dialysis modality on the relationship between the expression of Fas antigen, scavenger receptors and TNF-α system. METHODS.Four groups of subjects were evaluated: 10 non-dialyzed chronic renal failure (CRF) patients, 14 continuous ambulatory peritoneal dialysis (CAPD) patients, 16 hemodialysis (HD) patients and 10 normal controls (NC). Quantitative flow cytometry with dual antibody staining was applied to measure the expression of Fas antigen (CD95), scavenger receptors (CD36 and CD68), and tumor necrosis factor-receptor 2 (TNF-R2; CD120b) on monocytes. Correlations between these markers, total leukocyte number and differential counts were also checked. RESULTS.Our results demonstrated that lymphocytopenia can occur in ESRD patients. Monocyte counts were prominently decreased in the CRF group. The Fas expression on monocytes was significantly increased in HD patients compared with the other three groups. Its intensity in CRF and CAPD groups was also greater than in the NC group. The results of CD120b expression were similar to that of Fas expression. The monocyte CD36 expressions in dialysis groups (including CAPD and HD) were significantly higher than those in CRF and NC groups. Expression of CD68 was also significantly increased in HD patients. The Fas expression revealed positive correlation with CD120b (r=0.443, p=0.01) and CD68 (r=0.415, p=0.05). CONCLUSION.ESRD patients presented with accelerated expression of apoptotic markers and scavenger receptors combined with activation of the TNF-α system especially in HD patients. A positive correlation between Fas, TNF-R2 and scavenger receptors indicated a close relationship of apoptosis and the activation of TNF-α cytokine system on monocytes in ESRD patients.

It has been reported that long-term use of continuous-flow mechanical circulatory support devices (CF-MCSDs) may induce complications associated with diminished pulsatility. Pulsatile-flow mechanical circulatory support devices (PF-MCSDs) have the potential of overcoming these shortcomings with the advance of technology. In order to promote indepth understanding of PF-MCSD technology and thus encourage future MCSD innovations, engineering perspectives of PF-MCSD systems, including mechanical designs, drive mechanisms, working principles and implantation strategies, are reviewed in this article. Some emerging designs of PF-MCSDs are introduced and possible elements for next generation PF-MCSDs are identified.

The intra-aortic balloon pump (IABP) is a ventricular assist device that is used with a broad range of pre-, intra-, and postoperative patients undergoing cardiac surgery. Although the clinical efficacy of the IABP is well documented, the question of reduced efficacy when patients are nursed in the semi-recumbent position remains outstanding. The aim of the present work is therefore to investigate the underlying mechanics responsible for the loss of IABP performance when operated at an angle to the horizontal. Simultaneous recordings of balloon wall movement, providing an estimate of its diameter (D), and fluid pressure were taken at three sites along the intra-aortic balloon (IAB) at 0 and 45°. Flow rate, used for the calculation of displaced volume, was also recorded distal to the tip of the balloon. An in vitro experimental setup was used, featuring physiological impedances on either side of the IAB ends. IAB inflation at an angle of 45°showed that D increases at the tip of the IAB first, presenting a resistance

Background: The effect of the posture of semirecumbent patients on the hemodynamics and performance of intra-aortic balloon (IAB) were studied in vivo and in vitro. Methods: An IAB was inserted into a glass tube filled with saline, fully inflated and deflated using an intra-aortic balloon pump (IABP). Three successive cycles were filmed at 125 frames/s with the tube positioned at various angles between 0 ∞ (horizontal) and 90 ∞ (vertical). Pressure and flow were measured distal to both ends of the balloon. In parallel, coronary left anterior descending (LAD) flow velocity and aortic pressure were recorded in 6 patients using IABP, postcardiac surgery in the intensive care unit. Recordings were made when the patient was lying horizontally (recumbent) and when the patient's torso was inclined at 30 ∞ to the horizontal (semirecum-

Despite 50 years of research to assess the intra‐aortic balloon pump (IABP) effects on patients&#39; hemodynamics, some issues related to the effects of this therapy are still not fully understood. One of these issues is the effect of IABP, its inflation timing and duration on peripheral circulation autonomic controls. This work provides a systematic analysis of IABP effects on baroreflex using a cardiovascular hybrid model, which consists of computational and hydraulic submodels. The work also included a baroreflex computational model that was connected to a hydraulic model with a 40‐cm3 balloon. The IABP was operated at different inflation trigger timings (−0.14 to 0.31 s) and inflation durations (0.05–0.45 s), with time of the dicrotic notch being taken as t = 0. Baroreflex‐dependent parameters—afferent and efferent pathway activity, heart rate, peripheral resistance, and venous tone—were evaluated at each of the inflation trigger times and durations considered. Balloon early inf...

Purpose: Extracorporeal membrane oxygenation (ECMO) is a temporary mechanical circulatory assist method that offers circulatory as well as respiratory support efficiently via peripheral access; however, it is liable to a lot of complications. Limb ischemia, besides blood loss and infections, is one of the complications of ECMO but can be avoided utilizing a proper distal limb perfusion. Methods: We retrospectively reviewed 108 (56,4±14,9y) of our patients that went in need of veno-arterial extracorporeal life support in the University Hospital of Hamburg in the time between January 2014 until June 2015. The 108 patients received a femoral access to establish a sufficient blood flow, using a venous multistage cannula and arterial cannulation between 15 and 20 french. Distal limb perfusion was achieved with an introducer sheath (6-8 Fr) attached to the side-port of the arterial cannula in 53 cases. 10 (9,5%) patients developed signs of ischemia; four (3,7%) suffered from compartment syndrome in the leg containing the cannula and were in need of surgical treatment including fasciotomy, two patients required a below-knee amputation. The incidences of limb ischemia and limb ischemia requiring surgical intervention were significantly higher for the patients without distal leg perfusion compared to the patients treated with perfusion. (16,4% vs. 1,9% (p= 0,01) and 7,3% vs. 0% (p 0,04)). Increasing the diameter of the sheath showed no significant effect on the outcome, as well as the diameter of the arterial cannula, which was chosen between 15-19 Fr. None of the patients developing a compartment-syndrome with the need of surgical intervention survived the hospital stay. Conclusion: Use of distal perfusion helps to reduce one of the versatile complications patients suffer of in need of extracorporeal life support. Limb ischemia could be reduced significantly using an introducer sheath. Use of a distal-perfusion is a most reliable method of limb perfusion in peripheral VA-ECMO and should be established in every patient.

This work presents the development of a systemic mock circulation loop designed for testing of an axial flow, pneumatically operated left ventricular assist device (LVAD). A simulation of the heart proximal systemic circulation has been implemented that resembles the environment in which the LVAD will be operating, from where a hydraulic system, with several reconsiderations, has been constructed. An alternative method for measurement of the pulsatile aortic flow is suggested. A significant match between the simulated and measured system responses is demonstrated which substantially simplifies the search for parameter sets that determine the hemodynamic behavior of the system. Due to a high degree of flexibility and a wide range of hemodynamic states that can be simulated, the presented mock circulation is suitable for in-vitro experiments with the LVAD.

3.92) with arrhythmia and heart failure, 2.50 (2.31-2.70) with arrhythmia and diabetes, 3.19 (2.99-3.40) with heart failure and diabetes, and 4.95 (4.66-5.26) with all three conditions. In contrast, the adjusted hazard ratio was 1.25 for each 10-year increment in age. Conclusions: Within the frame of cardiac arrhythmia, heart failure, and diabetes mellitus, multimorbidity is common among US dialysis patients. Even more so than age, individual comorbid conditions and especially combinations of conditions are strongly associated with risk of cardiovascular death. Further progress toward improved survival will likely require both dialytic and non-dialytic therapies to address cardiovascular disease.

Background and Aim: Stem cell-based regenerative medicine has emerged as a transformative strategy to overcome the critical shortage of donor tissues and organs and to address degenerative and chronic diseases. This review synthesized recent advances in the application of embryonic, adult, and induced pluripotent stem cells across neurological, cardiovascular, endocrine, and other major organ systems, with a focus on preclinical and clinical evidence supporting their therapeutic potential. Materials and Methods: This review analyzed the current scientific literature, highlighting key technological enablers, such as 3D and 4D bioprinting, biomaterial scaffolds, and microfluidic organ-on-a-chip platforms that are driving the development of functional tissue constructs and enhancing disease modeling and drug screening. Results: Major trends identified included the successful differentiation of iPSCs into diseaserelevant cell types for personalized therapies, the paracrine-mediated repair mechanisms of mesenchymal stem cells, and the growing feasibility of engineering vascularized, complex tissues through advanced biofabrication techniques. Despite significant progress, challenges in vascular integration, long-term engraftment, immune compatibility, and clinical reproducibility remain critical barriers to translation. Conclusion: This review underscores the importance of standardizing cell sources, delivery protocols, and functional assessment methods, and calls for future research to focus on scalable manufacturing, smart biomaterials, and robust preclinical models. By integrating biological insights with engineering innovations, this field is poised to accelerate the clinical realization of regenerative therapies.

Cardiovascular complications are the leading cause of death after renal transplantation, accounting for an estimated 36% of deaths in patients with functioning grafts (1). In order to improve the life expectancy of these patients it is crucial to recognize what are the most important risk factors contributing to the excessive cardiovascular risk in this population. These risk factors may be related to the original renal disease, to dialysis, or to the renal transplant.

Electrical stimulation of the L-3,4 dermatome during treadmill walking is proposed as a gait training modality in incomplete spinal cord injured patients. The dermatome stimulation proved to be efficient in diminishing the extensor tone occuring after loading of the paralyzed limb during the stance phase of walking and resulting in improved flexion of the leg during the swing phase.

With the assistance of crutches and functional electrical stimulation (FES),we are able to restore standing and simple gait in some spinal cord injured(SCI) patients. In present rehabilitative systems, the patient divides the gait cycleinto stance and swing phases via pushbuttons mounted on the handles of thecrutches, which arehard‐wired to the functional electrical stimulator. The surface‐mounttechnology based telemetry system, which makes use of the radiofrequency mediumat 40 MHz, was developed toprovide wireless control of the FES system. Signals from crutch pushbuttonswere coded and transferred from the transmitter to the receiver. The receiverwas firmly attached to the patient&#39;s waist and was connected to thestimulator.

Clinical use of extracorporeal membrane oxygenation (ECMO) and carbon dioxide removal (ECCO 2R) have become well established techniques for the treatment of severe respiratory failure; however they require full cardiopulmonary bypass, representing major procedures with high morbidity. We theorized the possibility of an efficient low flow veno-venous extracorporeal membrane gas exchange method. Four mongrel 12 kg dogs were submitted to veno-venous extracorporeal membrane gas exchange via a jugular dialysis catheter using a low flow (10 ml/min) roller pump and a membrane oxygenator for a period of four hours. Respiratory rate was set at 4 breaths/min with a FiO 2 of 21% and ventilatory dead space was increased. Adequate gas exchange was obtained (pO 2139, pCO 224, Sat 99.4%), without major hemodynamic changes or hematuria. Our results demonstrate the feasibility of a low flow, less aggressive system. Further research should be considered.

We developed the STIMBELT, an electrical stimulation system that comprises a lumbar belt with up to eight pairs of embedded electrodes and an eight-channel electronic stimulator.The STIMBELT is an assistive system for the treatment of low-back pain (LBP).We describe here technical details of the system and summarize the results of its application in individuals with subacute and chronic LBP. The direct goals of the treatment were to relieve pain, reduce muscle spasms, increase strength and range of motion, and educate individuals with LBP in reducing the chances of its reoccurrence.The outcome measures include: a Visual Analogue Scale (VAS), the Oswestry LBP Disability Questionnaire, the Short Form (SF)-12 health survey, and the Manual Muscle Test. The results indicate significant benefits for individuals who use the STIMBELT in addition to the conventional therapy as opposed to only the conventional therapy.

Electrical stimulation of the L-3,4 dermatome during treadmill walking is proposed as a gait training modality in incomplete spinal cord injured patients. The dermatome stimulation proved to be efficient in diminishing the extensor tone occuring after loading of the paralyzed limb during the stance phase of walking and resulting in improved flexion of the leg during the swing phase.

With the assistance of crutches and functional electrical stimulation (FES),we are able to restore standing and simple gait in some spinal cord injured(SCI) patients. In present rehabilitative systems, the patient divides the gait cycleinto stance and swing phases via pushbuttons mounted on the handles of thecrutches, which arehard‐wired to the functional electrical stimulator. The surface‐mounttechnology based telemetry system, which makes use of the radiofrequency mediumat 40 MHz, was developed toprovide wireless control of the FES system. Signals from crutch pushbuttonswere coded and transferred from the transmitter to the receiver. The receiverwas firmly attached to the patient&#39;s waist and was connected to thestimulator.

The influence of functional electricallystimulated ankle plantar flexors on the swinging lower extremitywas studied in incomplete spinal cord injured persons.Stimulation sequences with different time and frequencyparameters were delivered to ankle plantar flexors andknee extensors and to the peroneal nerve. The results ofkinematic assessment showed that stimulated calf musclesprovide noticeable forward and upward propulsion to theswinging leg.

Sensory supported electrical stimulation of the peroneal nerve during treadmill walking is proposed as a gait-training modality in incomplete spinal cord injury (SCI) patients. A multisensor device provides information on the tilt of the shank during gait. The information provided significantly improves the triggering instant of the electrical stimulation. Simultaneously, swing-phase

The sit-to-stand transfer of paraplegic patients using functional electrical stimulation (FES) of the knee extensors and arm support was analyzed in the study. In a group of 8 completely paralyzed subjects who were trained FES users, kinematic and dynamic parameters were recorded during standing up trials. A contactless optical system was used to assess the human body motion. The forces acting on the human body were measured by multi-axis force transducers. On the basis of recursive Newton-Euler inverse dynamic analysis, the forces and torques acting on the body joints were calculated. The joint moments in the lower and upper extremities during the sit-to stand task are presented in this paper. The influences of the patient's strength, FES training duration, and rising strategy on the joint loading are discussed.

After a program of therapeutic electrical stimulation, 3 groups of incomplete spinal cord injured (SCI) patients were identified, those in whom an improvement of both voluntary and stimulated muscle force was observed, those with an increase in stimulation response only, and patients in whom no effect of electrical stimulation training could be recorded. As it is difficult to predict the outcome of the electrical stimulation rehabilitation process, a diagnostic procedure was developed to predict soon after accidents which incomplete SCI patients are candidates for permanent use of a functional electrical In the last few decades, advances in traffic control and motor vehicle engineering together with more efficient first aid and improved transport to emergency centers have resulted in a reduction in the number of complete spinal cord injured (SCI) patients. As a consequence, more incomplete injury cases are arriving in spinal units. There are more incomplete tetraplegic than paraplegic cases. About one-half of the incomplete SCI patients recover and need no orthotic aid. In these patients, functional electrical stimulation (FES) can be used as a therapeutic treatment in the early posttrauma phase. The other incomplete SCI patients are candidates for functional chronic use of FES rehabilitative aids. Incomplete lesions of the spinal cord are characterized by 3 different kinds of muscles, normal, centrally denervated (spastic), and peripherally denervated (flaccid). All 3 kinds of muscles can be found, not only in the lower extremity of an incomplete SCI

Selective apheresis procedures have been developed to target specific molecules, antibodies, or cellular elements in a variety of diseases. The advantage of the selective apheresis procedures over conventional therapeutic plasmapheresis is preservation of other essential plasma components such as albumin, immunoglobulins, and clotting factors. These procedures are more commonly employed in Europe and Japan, and few are available in the USA. Apheresis procedures discussed in this review include the various technologies available for low‐density lipoprotein (LDL) apheresis, double filtration plasmapheresis (DFPP), cryofiltration, immunoadsorption procedures, adsorption resins that process plasma, extracorporeal photopheresis, and leukocyte apheresis. J. Clin. Apheresis 28:20–29, 2013. © 2013 Wiley Periodicals, Inc.

The study is presenting our long-term clinical results after freestyle stentless aortic root bioprosthesis replacement in patients with severe aortic insufficiency with ascending aortic aneurysm. Methods: Seventy-seven patients with ascending aortic aneurysms and aortic valve insufficiency underwent a total root replacement procedure using a stentless "Freestyle" valve (Medtronic Inc., Minneapolis, Minnesota). There were 50 (64.9%) men and 27 (35.1%) women. Mean age was 68.7 ± 11.1 years. The surgical procedure used a complete root replacement. Concomitant procedures included coronary artery bypass grafting in 15 (19.5%) patients. Results: The mean cardiopulmonary bypass time was 130.3 ± 26.4 minutes and total aortic cross clamp time was 99.5 ± 23.6 minutes. Hospital mortality was 2.6%. The median follow-up time was 11.2 years. The 5-and 10-years freedom from aortic valve reoperation were 97.4 ± 1.2% and 93.4 ± 4.9%, respectively. During 10 years follow up, there were 14 late deaths; 4 deaths were cardiac, and 10 deaths were noncardiac. Valve-related deaths were attributable to thromboembolism in 1 patient, endocarditis in 2 patients, and congestive heart failure in 1 patient. The freestyle stentless aortic root bioprosthesis offered good clinical outcomes, in terms of survival and structural valve deterioration. The Freestyle valve is a viable option for use in patients undergoing bioprosthetic aortic valve replacement and expected desire for long-term durability.

Implantable left ventricular assist device systems (LVAS) are increasingly being used to bridge patients to heart transplantation because of the limited number of available donor hearts. This prospective, multicenter trial was designed to evaluate the usefulness of the HeartMate vented electric (VE) LVAS as a bridge to transplantation in Japan. Between November 2001 and June 2003, six patients with end-stage heart failure [New York Heart Association (NYHA) class IV] were supported with the LVAS and five of the six were able to implement the evaluation (one dropped out). The five were men with an average age of 38.6 years and were supported for 2390 cumulative days (6.6 years). Average preimplant cardiac index improved from 1.93 l/min/m(2) to a 3.79 l/min/m(2) VAD flow index at the end of the clinical trial. All five patients improved to NYHA class I or II, survived more than 1 year, and one patient was discharged from the hospital. Mean LVAS support duration was 478 days (range 390-...

Background: Prosthetic device-associated infections, frequently complicated by antimicrobial resistance (AMR), pose a severe clinical challenge. In Nigeria, limited regional data on pathogen prevalence and susceptibility impairs effective treatment. This study aimed to identify the primary bacterial agents and their resistance profiles in prosthetic infections at a major Nigerian orthopedic hospital.

Methods: A cross-sectional study was conducted from June to November 2024 at the National Orthopedic Hospital, Enugu, Nigeria. One hundred samples from patients with clinical signs of infection post-prosthetic implantation were analyzed. Bacterial pathogens were identified via standard culture, and antimicrobial susceptibility was determined using the Kirby-Bauer disk diffusion method.

Results: Bacterial growth was confirmed in 65% of samples (n=65). Staphylococcus aureus was the predominant pathogen (38.5%), followed by Escherichia coli (23.1%) and Pseudomonas aeruginosa (15.4%). Susceptibility testing revealed alarmingly high resistance to common antibiotics, with 76.9% of isolates resistant to Erythromycin and 69.2% to Amoxicillin-Clavulanate. Conversely, Levofloxacin and Meropenem demonstrated the highest efficacy, with sensitivity rates of 76.9% and 69.2%, respectively. Infections were significantly more prevalent in males (p=0.030) and the 30–60-year age group (p=0.050).

Conclusion: This study confirms a high prevalence of multidrug-resistant pathogens, led by S. aureus, in prosthetic device infections in Enugu. The findings highlight the inadequacy of empirical therapies using common antibiotics and strongly support the use of fluoroquinolones or carbapenems. These results underscore the urgent need for enhanced infection control, antibiotic stewardship, and routine surveillance to combat AMR.

The efficacy and feasibility of the insulin infusion pump in pregnancy were examined in seven class D to FR diabetics, maintained on the pump at home from 10 to 29 wk gestation until delivery. An improvement in glucose control was achieved within the first month and sustained to term. Home monitoring demonstrated a fall in mean blood glucose levels from 135 mg/dl range 98–175, prepump) to 104 mg/dl (range 84–120) and a 25–30% reduction in standard deviations during pump treatment. Furthermore, glycosylated hemoglobin levels were normalized in each patient. During periodic inpatient evaluations, mean 24-h plasma glucose levels were slightly, but not significantly, lower after pump treatment (97 vs. 86 mg/dl). However, glycemic excursions were strikingly diminished; MAGE values and standard deviations fell by 45% and 34%, respectively. The total daily insulin dose required at the start of pump treatment was 31% less than the conventional dose used before the pump (P &lt; 0.002). There...

Keratoprosthesis (KPro) implantation is frequently the only recourse for patients with severe corneal disease. However, problems arise due to inadequate biointegration of the KPro, particularly the PMMA optical cylinder, such as tissue detachment, tissue melting, or eyethreatening infection in the interface. Here, using the AuroKPro as a model prosthesis, a surface functionalisation approach-coating the optical cylinder with nano-hydroxyapatite (nHAp)-was trialled in rabbit eyes with and without a proceeding chemical injury. In chemically injured eyes, which simulated total limbal epithelial stem cell deficiency, clear benefits were conferred by the coating. The total modified Hackett-McDonald score and area of tissue apposition differences 12 weeks after implantation were 5.0 and 22.5%, respectively. Mechanical push-in tests revealed that 31.8% greater work was required to detach the tissues. These differences were less marked in uninjured eyes, which showed total score and tissue apposition differences of 2.5 and 11.5%, respectively and a work difference of 23.5%. The improved biointegration could be contributed by the attenuated expression of fibronectin (p = 0.036), collagen 3A1 (p = 0.033), and α-smooth muscle actin (p = 0.045)--proteins typically upregulated during non-adherent fibrous capsule envelopment of bioinert material--adjacent to the optical cylinders. The coating also appeared to induce a less immunogenic milieu in the ocular surface tissue, evidenced by the markedly lower expression of tear proteins associated with immune and stimulus responses. Collectively, the level of these tear proteins in eyes with coated prostheses was 1.1 ± 13.0% of naïve eyes: substantially lower than with non-coated KPros (246.5 ± 79.3% of naïve, p = 0.038). Together, our results indicated that nHAp coating may reduce the risk of prosthesis failure in severely injured eyes, which are representative of the cohort of KPro patients.

In this study we apply methods to determine the tendency for thrombus formation in different central venous catheters (CVC) models associated with flow rate variation. To calculate the thrombogenic potential, we proposed a new numerical model of the platelet lysis index (PLI) equation. To compare the results of PLI and flow rate in different models of catheters, numerical calculations were performed on three different tips of CVC. The results showed that the PLI increases as a power function of the flow rate independent of the type of CVC. This study evidenced that the higher the blood flow rate used in the catheter, the greater the potential for thrombus formation. The PLI computed at the catheter outlet presented higher values when compared to the values computed at the vein outlet indicating that the blood flow through the CVC arterial lumen presents a proportionally larger thrombogenic potential when compared to the blood flow that leaves the vein towards the atrium. This findin...

Heart surgeries using extracorporeal circulation are a common practice. Artificial circulatory devices represent an indispensable tool in clinical practice. Blood flow through artificial devices is associated to red blood cells damage and/or thrombus formation. Is generally accepted that the presence of high turbulent shear stresses generated in the flow fields of artificial devices are partially responsible for the levels of red blood cells destruction, or hemolysis. Investigating the effect of turbulent shear stress on hemolysis is of prime importance to research work related to artificial devices. Hemolysis potential can be expressed as function of the shear stresses magnitude acting on blood cells and their exposure time to the shear stresses. The present work presents the use of two techniques used to study the incoming flow in an arterial blood filter. The general structure of the flow field was analyzed using the dye injection technique. A laser Doppler anemometer was used to...

The central venous catheter that is inserted in patients undergoing hemodialysis can cause hemodynamic instability and trigger complications such as thrombus formation. The objective of this study was to investigate hemostatic and numerical influences on thrombus formation in patients undergoing hemodialysis with a central venous catheter. Participants were assigned to three groups: I: clinical and laboratorial healthy individuals matched by sex and age (controls); II: participants after one month of insertion of the catheter and III: participants after 4 months of insertion of the catheter. Platelet activation was investigated by GPIIb/IIIa and p-selectin expressions using flow cytometry. A three-dimensional model of the catheter was constructed in the numerical simulation for the calculation of partial differential equation of a platelet activation model. A significant difference was detected by the expression of p-selectin comparing the group I (33.42 ± 4.74), group II (40.79 ± 5...

Acute renal failure (ARF) is currently more frequently seen as part of a more complex syndrome defined by sepsis and/or multiple organ failure. Evolution in the field of hemodialysis has led to a parallel development of new systems for continuous renal replacement therapy (CRRT) in critically ill patients. The various CRRT modalities differ in the type of vascular access, application of diffusive or convective clearance (or a combination of both), and location where the replacement fluid enters the circuit. CRRTs have certainly facilitated the management of critically ill patients with ARF combined with cardiovascular instability, severe fluid overload, hypercatabolism, cerebral edema, adult respiratory distress syndrome, lactic acidosis, sepsis or other inflammatory syndromes, crush syndrome, congestive heart failure, and cardiopulmonary bypass. Continuous therapies incorporate several advantages including improved hemodynamic stability, optimal fluid balance, gradual urea removal, elimination of septic mediators, and the possibility of unlimited parenteral nutrition. Major difficulties and unsolved problems of CRRT are the ongoing necessity for continuous anticoagulation, considerable loss of amino acids, vitamins, trace elements, potassium, phosphate, and some drugs as well as immobilization of the patient. The advantages of CRRT should theoretically translate into improved outcomes of critically ill ARF patients, but the superiority of continuous modalities in terms of outcomes is still controversial, despite encouraging results in some clinical trials.

BackgroundA higher sodium (Na) dialysate concentration is recommended during renal replacement therapy (RRT) of acute kidney injury (AKI) to improve intradialytic hemodynamic tolerance, but it may lead to Na loading to the patient. We aimed to evaluate Na flux according to Na dialysate and infusate concentrations at 140 and 145 mmol/L during hemodialysis (HD) and hemodiafiltration (HDF).MethodsFourteen AKI patients that underwent consecutive HD or HDF sessions with Na dialysate/infusate at 140 and 145 mmol/L were included. Per‐dialytic flux of Na was estimated using mean sodium logarithmic concentration including diffusive and convective influx. We compared the flux of sodium between HD140 and 145, and between HDF140 and 145.ResultsNine HD140, ten HDF140, nine HD145, and 11 HDF145 sessions were analyzed. A Na gradient from the dialysate/replacement fluid to the patient was observed with dialysate/infusate Na at 145 mmol/L in both HD and HDF (p = 0.01). The comparison of HD145 to HD1...

Introduction: Bordetella holmesii is a Gram-negative coccobacillus involved in different infections mostly described in case reports. Prosthetic joint infections in relation to this pathogen are rare. Here, we present the third case of B. holmesii in a patient without anatomical or functional spleen dysfunction. Case report: The patient was a 62-year-old female with a total knee prosthesis implanted in 1997 that required multiple replacements of the femoral component due to aseptic loosening in the past years. The patient was admitted to our hospital for an elective replacement surgery due to new radiological signs of loosening. B. holmesii was isolated from synovial fluid obtained during surgery. The identification was performed by matrix-assisted laser desorption ionization–time of flight mass spectrometry and confirmed by 16S rRNA gene amplification and sequencing. Antibiotic treatment was started but 14 days after surgery the patient presented pain and joint effusion. An arthroc...