Application of 3D Printing in Bone Grafts.

The application of 3D printing in bone grafts is gaining in importance and is becoming more and more popular. The choice of the method has a direct impact on the preparation of the patient for surgery, the probability of rejection of the transplant, and many other complications. The aim of the article is to discuss methods of bone grafting and to compare these methods. This review of literature is based on a selective literature search of the PubMed and Web of Science databases from 2001 to 2022 using the search terms "bone graft", "bone transplant", and "3D printing". In addition, we also reviewed non-medical literature related to materials used for 3D printing. There are several methods of bone grafting, such as a demineralized bone matrix, cancellous allograft, nonvascular cortical allograft, osteoarticular allograft, osteochondral allograft, vascularized allograft, and an autogenic transplant using a bone substitute. Currently, autogenous grafting, which involves removing the patient's bone from an area of low aesthetic importance, is referred to as the gold standard. 3D printing enables using a variety of materials. 3D technology is being applied to bone tissue engineering much more often. It allows for the treatment of bone defects thanks to the creation of a porous scaffold with adequate mechanical strength and favorable macro- and microstructures. Bone tissue engineering is an innovative approach that can be used to repair multiple bone defects in the process of transplantation. In this process, biomaterials are a very important factor in supporting regenerative cells and the regeneration of tissue. We have years of research ahead of us; however, it is certain that 3D printing is the future of transplant medicine.

An Overview of Essential Microelements and Common Metallic Nanoparticles and Their Effects on Male Fertility.

Numerous factors affect reproduction, including stress, diet, obesity, the use of stimulants, or exposure to toxins, along with heavy elements (lead, silver, cadmium, uranium, vanadium, mercury, arsenic). Metals, like other xenotoxins, can cause infertility through, e.g., impairment of endocrine function and gametogenesis or excess production of reactive oxygen species (ROS). The advancement of nanotechnology has created another hazard to human safety through exposure to metals in the form of nanomaterials (NMs). Nanoparticles (NPs) exhibit a specific ability to penetrate cell membranes and biological barriers in the human body. These ultra-fine particles (<100 nm) can enter the human body through the respiratory tract, food, skin, injection, or implantation. Once absorbed, NPs are transported to various organs through the blood or lymph. Absorbed NPs, thanks to ultrahigh reactivity compared to bulk materials in microscale size, disrupt the homeostasis of the body as a result of interaction with biological molecules such as DNA, lipids, and proteins; interfering with the functioning of cells, organs, and physiological systems; and leading to severe pathological dysfunctions. Over the past decades, much research has been performed on the reproductive effects of essential trace elements. The research hypothesis that disturbances in the metabolism of trace elements are one of the many causes of infertility has been unquestionably confirmed. This review examines the complex reproductive risks for men regarding the exposure to potentially harmless xenobiotics based on a series of 298 articles over the past 30 years. The research was conducted using PubMed, Web of Science, and Scopus databases searching for papers devoted to in vivo and in vitro studies related to the influence of essential elements (iron, selenium, manganese, cobalt, zinc, copper, and molybdenum) and widely used metallic NPs on male reproduction potential.

The analysis of Fe-dependent serum enzymes in severe COVID-19 with a pulmonary thrombotic event.

Introduction: COVID-19 patients in critical condition requiring ICU admission are more likely to experience thromboembolic complications, especially pulmonary embolism. Since the outbreak of coronavirus disease 2019 (COVID-19), clinicians have struggled with the attempt to diagnose and manage the severe and fatal complications of COVID-19 appropriately. Several reports have described significant procoagulatory events, including life-threatening pulmonary embolism, in these patients. The aim of the study was to analyze the results of selected serum enzymes in patients with a radiologically confirmed pulmonary thrombotic event based on the pulmonary tissue involvement assessed in a computed tomography (CT) scan. Material and methods: The retrospective study covered a group of 226 COVID-19 patients. Groups were divided based on the degree of lung tissue involvement in CT examinations, including patients with confirmed pulmonary embolism. The analyzed group consisted of 136 men and 90 women with mean age of 70 years. Results: The group consisted of patients with < 50% of lung volume changes who had higher parameter values in each analyzed parameter, except red blood cells (RBC) (p < 0.05). Especially, the level of ferritin was much higher in the first group (p = 0.000008). Elevated ferritin levels were observed in all patients with lung tissue involvement. Discussion: This line of research is critical in order to assess the predisposing conditions for pulmonary embolism occurrence in COVID-19, which can be used as a predictive factor for course of the disease. The conducted research will resolve whether there is a relationship between the selected laboratory parameters and the occurrence of pulmonary embolism in patients with COVID-19. Conclusions: The study demonstrated that elevated levels of several inflammatory and thrombotic parameters such as ferritin, D-dimer, C-reactive protein (CRP) as well as hemoglobin do not correlate with the degree of lung tissue involvement in the computed tomography image.