In orthopedics, bone fixation imposes the use of implants in almost all cases. Over time, the materials used for the implant have evolved from inert materials to those that mimic the morphology of the bone. Therefore, bioabsorbable, biocompatible, and bioactive materials have emerged. Our study aimed to review the main types of implant materials used in orthopedics and present their advantages and drawbacks. We have searched for the pros and cons of the various types of material in the literature from over the last twenty years. The studied data show that consecrated metal alloys, still widely used, can be successfully replaced by new types of polymers. The data from the literature show that, by manipulating their composition, the polymeric compounds can simulate the structure of the different layers of human bone, while preserving its mechanical characteristics. In addition, manipulation of the polymer composition can provide the initiation of desired cellular responses. Among the implanting materials, polyurethane is distinguished as the most versatile polymeric material for use both as orthopedic implants and as material for biomechanical testing of various bone reduction and fixation techniques.

Mesenchymal stem cells (MSCs) have emerged as a relevant strategy in regenerative medicine due to their multipotent differentiation capacity, immunomodulatory properties, and therapeutic applications in various medical fields. This review explores the therapeutic use of MSCs, focusing on their role in treating autoimmune disorders and neoplastic diseases and in tissue regeneration. We discuss the mechanisms underlying MSC-mediated tissue repair, including their paracrine activity, migration to injury sites, and interaction with the immune system. Advances in cellular therapies such as genome engineering and MSC-derived exosome treatments further enhance their applicability. Key methodologies analyzed include genomic studies, next-generation sequencing (NGS), and bioinformatics approaches to optimize MSC-based interventions. Additionally, we reviewed preclinical and clinical evidence demonstrating the therapeutic potential of MSCs in conditions such as graft-versus-host disease, osteoarthritis, liver cirrhosis, and neurodegenerative disorders. While promising, challenges remain regarding standardization, long-term safety, and potential tumorigenic risks associated with MSC therapy. Future research should focus on refining MSC-based treatments to enhance efficacy and minimize risks. This review underscores the need for large-scale clinical trials to validate MSC-based interventions and fully harness their therapeutic potential.

Sentinel lymph node biopsy (SLNB) is a surgical procedure that has been used in patients with cutaneous melanoma for nearly 30 years. It is used for both staging and regional disease control with minimum morbidity, as proven by numerous worldwide prospective studies. It has been incorporated in the recommendations of national and professional guidelines. In this article, we provide a summary of the general information on SLNB in the clinical guidelines for the management of cutaneous malignant melanoma (American Association of Dermatology, European Society of Medical Oncology, National Comprehensive Cancer Network, and Cancer Council Australia) and review the most relevant literature to provide an update on the existing recommendations for SLNB.

Chronic kidney disease (CKD) is a major public health issue, due to its effect on the quality of life of patients and by the huge costs incurred in treating this disease. It is an irreversible process, characterized by the progressive loss of functional nephrons. CKD ultimately requires the support of renal function by dialysis or even renal transplantation. It has a multiple etiology, but the most common causes remain arterial hypertension and diabetes. High arterial blood pressure affects the target organs (kidneys) and this leads to a vicious circle involved in maintaining high blood pressure. Arterial hypertension is closely related to the renal pathology of CKD. The result of excessive activation of the renin angiotensin system (RAS) is increased angiotensin II (Ang II), which acts upon the systemic circulation and especially upon the kidneys. The outcome is high blood pressure and also the stimulation of proinflammatory and profibrotic effects in the kidneys. Collectively these ultimately lead to CKD. The aim of this review was to provide a brief overview of the pathophysiological associations between CKD, arterial hypertension, and Ang II.

Homocysteine (Hcy) is becoming a well-established risk factor for cardiovascular disease (CVD), mainly involving endothelial dysfunction and atherogenesis. Endothelial dysfunction is reflected primarily in the complex regulation of the main physiological and pathophysiological processes. There is increasing evidence regarding abnormally high concentrations of plasma total homocysteine, or plasma hyperhomocysteinemia, contributing to endothelial dysfunction, inflammation, and CVD. This clinical and experimental study examined the connection between Hcy and cardiovascular disease risk. Homocysteine is a marker of total vascular damage that must be monitored and controlled as early as possible. Dietary and lifestyle changes are recommended for most patients with hyperhomocysteinemia (Hhcy). The purpose of this paper is to review the data from the specialized literature that demonstrate that there is a direct link between endothelial injury and increased homocysteine levels, identifying existing evidence, describing new mechanisms, and exploring potential new therapeutic options. These aspects continue to be debated, and additional efforts are required to refine therapeutic strategies and to investigate the potential implications of Hcy in health and disease.

Autoimmune dermatological diseases (AIDD) encompass a diverse group of disorders characterized by aberrant immune responses targeting the skin and its associated structures. In recent years, emerging evidence suggests a potential involvement of the renin–angiotensin system (RAS) in the pathogenesis and progression of these conditions. RAS is a multicomponent cascade, primarily known for its role in regulating blood pressure and fluid balance. All of the RAS components play an important role in controlling inflammation and other immune responses. Angiotensin II, the main effector, acts on two essential receptors: Angiotensin Receptor 1 and 2 (AT1R and AT2R). A disturbance in the axis can lead to many pathological processes, including autoimmune (AI) diseases. AT1R activation triggers diverse signaling cascades involved in inflammation, fibrosis and tissue remodeling. Experimental studies have demonstrated the presence of AT1R in various cutaneous cells and immune cells, further emphasizing its potential contribution to the AI processes in the skin. Furthermore, recent investigations have highlighted the role of other RAS components, beyond angiotensin-converting enzyme (ACE) and Ang II, that may contribute to the pathophysiology of AIDD. Alternative pathways involving ACE2, Ang receptors and Ang-(1-7) have been implicated in regulating immune responses and tissue homeostasis within the skin microenvironment. Understanding the intricate involvement of the RAS in AIDD may provide novel therapeutic opportunities. Targeting specific components of the RAS, such as angiotensin receptor blockers (ARBs), ACE inhibitors (ACEIs) or alternative RAS pathway modulators, could potentially ameliorate inflammatory responses, reduce tissue damage and lessen disease manifestations. Further research is warranted to outline the exact mechanisms underlying RAS-mediated immune dysregulation in AIDD. This abstract aims to provide a concise overview of the intricate interplay between the RAS and AIDD. Therefore, we elaborate a systematic review of the potential challenge of RAS in the AIDD, including psoriasis, systemic sclerosis, vitiligo, lupus erythematosus and many more.