There is great interest in the development of prosthetic limbs capable of complex activities that are wirelessly connected to the patient’s neural system. Although some progress has been achieved in this area, one of the main problems encountered is the selective acquisition of nerve impulses and the closing of the automation loop through the selective stimulation of the sensitive branches of the patient. Large-scale research and development have achieved so-called “cuff electrodes”; however, they present a big disadvantage: they are not selective. In this article, we present the progress made in the development of an implantable system of plug neural microelectrodes that relate to the biological nerve tissue and can be used for the selective acquisition of neuronal signals and for the stimulation of specific nerve fascicles. The developed plug electrodes are also advantageous due to their small thickness, as they do not trigger nerve inflammation. In addition, the results of the conducted tests on a sous scrofa subject are presented.

In this article, we present our research achievements regarding the development of a remote sensing system for motor pulse acquisition, as a first step towards a complete neuroprosthetic arm. We present the fabrication process of an implantable electrode for nerve impulse acquisition, together with an innovative wirelessly controlled system. In our study, these were combined into an implantable device for attachment to peripheral nerves. Mechanical and biocompatibility tests were performed, as well as in vivo testing on pigs using the developed system. This testing and the experimental results are presented in a comprehensive manner, demonstrating that the system is capable of accomplishing the requirements of its designed application. Most significantly, neural electrical signals were acquired and transmitted out of the body during animal experiments, which were conducted according to ethical regulations in the field.

The natural differences between human-made electronics and biological tissues constitute a huge challenge in materials and the manufacturing of next-generation bioelectronics. As such, we performed a series of consecutive experiments for testing the biofunctionality and biocompatibility for device implantation, by changing the exterior chemical and physical properties of electronics coating it with silicone or hydrogels. In this article, we present a comparison of the main characteristics of an electronic device coated with either silicone or hydrogel (GelMa). The coating was performed with a bioprinter for accurate silicone and hydrogel deposition around different electronic chips (Step-Down Voltage Regulator U3V15F5 from Pololu Corporation). The results demonstrate that the hydrogel coating presents an augmented biomechanical and biochemical interface and superior biocompatibility, lowers foreign body response, and considerably extends the capabilities for bioelectronic applications.

Malignant melanoma is a deadly form of skin cancer, and prompt diagnosis is a key factor in providing adequate, life-saving therapy. A 75-year-old man, with long-standing type 2 diabetes mellitus, presented with a 2- to 3-year history of right heel ulcer. He had received various therapies for a diagnosis of diabetic foot ulcer, to no avail. Physical examination showed a black, fungating ulcerated lesion on his right heel, with minimal bleeding. No inguinal lymphadenopathy was palpated. A biopsy was done, which revealed BRAF-negative malignant melanoma, with a vertical growth phase, Breslow 3.1 mm, ulceration, 11 mitoses/mm², Clark level IV, no lymphatic or vascular invasion observed. Right inguinal lymph node sampling suggested no involvement, but PET-CT suggested pulmonary, right inguinal lymph node and bone involvement. The patient was referred to the oncologists. Written informed consent for publication was given by the patient. Diabetic foot ulcers are a frequently encountered, but serious complication of diabetes mellitus. Delayed healing is often seen, despite adequate therapy. The differential diagnosis of diabetic foot ulcers is vast and includes neoplasia. When a foot ulcer fails to heal, other differential diagnoses must be considered, in order for the patient to receive adequate therapy. Here specialist consultations, including dermatology consultations, could improve chances of delivering the right therapy promptly. This is a factor underlying the emphasis on a multidisciplinary approach to foot ulcer therapy. Our presentation – reported according to the CARE guidelines – also illustrates the fact that failure to reach a timely diagnosis may deny the patient the opportunity to receive adequate treatment. In such cases, “delayed therapy becomes denied (or failed) therapy”, paraphrasing the old adage “Justice delayed is justice denied”.