Biomaterials for extrusion-based bioprinting and biomedical applications.

Amongst the range of bioprinting technologies currently available, bioprinting by material extrusion is gaining increasing popularity due to accessibility, low cost, and the absence of energy sources, such as lasers, which may significantly damage the cells. New applications of extrusion-based bioprinting are systematically emerging in the biomedical field in relation to tissue and organ fabrication. Extrusion-based bioprinting presents a series of specific challenges in relation to achievable resolutions, accuracy and speed. Resolution and accuracy in particular are of paramount importance for the realization of microstructures (for example, vascularization) within tissues and organs. Another major theme of research is cell survival and functional preservation, as extruded bioinks have cells subjected to considerable shear stresses as they travel through the extrusion apparatus. Here, an overview of the main available extrusion-based printing technologies and related families of bioprinting materials (bioinks) is provided. The main challenges related to achieving resolution and accuracy whilst assuring cell viability and function are discussed in relation to specific application contexts in the field of tissue and organ fabrication.

Effect of a multidisciplinary team approach in patients with diabetic foot ulcers on major adverse limb events (MALEs): systematic review and meta-analysis for the development of the Italian guidelines for the treatment of diabetic foot syndrome.

The treatment of patients with diabetic foot ulcers (DFUs) is extremely complex, requiring a comprehensive approach that involves a variety of different healthcare professionals. Several studies have shown that a multidisciplinary team (MDT) approach is useful to achieve good clinical outcomes, reducing major and minor amputation and increasing the chance of healing. Despite this, the multidisciplinary approach is not always a recognized treatment strategy. The aim of this meta-analysis was to assess the effects of an MDT approach on major adverse limb events, healing, time-to-heal, all-cause mortality, and other clinical outcomes in patients with active DFUs. The present meta-analysis was performed for the purpose of developing Italian guidelines for the treatment of diabetic foot with the support of the Italian Society of Diabetology (Società Italiana di Diabetologia, SID) and the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD). The study was performed using the Grading of Recommendations Assessment, Development, and Evaluation approach. All randomized clinical trials and observational studies, with a duration of at least 26 weeks, which compared the MDT approach with any other organizational strategy in the management of patients with DFUs were considered. Animal studies were excluded. A search of Medline and Embase databases was performed up until the May 1st, 2023. Patients managed by an MDT were reported to have better outcomes in terms of healing, minor and major amputation, and survival in comparison with those managed using other approaches. No data were found on quality of life, returning-to-walking, and emergency admission. Authors concluded that the MDT may be effective in improving outcomes in patients with DFUs.

Development of the Italian clinical practice guidelines for the treatment of diabetic foot syndrome: design and methodological aspects.

AIMS: Diabetic foot syndrome (DFS) and its complications are a growing public health concern. The Italian Society of Diabetology (SID) and the Italian Association of Clinical Diabetologists (AMD), in collaboration with other scientific societies, will develop the first Italian guidelines for the treatment of DFS. METHODS: The creation of SID/AMD Guidelines is based on an extended work made by 19 panelists and 12 members of the Evidence Review Team. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology has been used to decide aims, reference population, and target health professionals. Clinical questions have been created using PICO (Patient, Intervention, Comparison, Outcome) conceptual framework. The definition of questions has been performed using a two-step web-based Delphi methodology, a structured technique aimed at obtaining by repeated rounds of questionnaires a consensus opinion from a panel of experts in areas wherein evidence is scarce or conflicting, and opinion is important. RESULTS: The mean age of panelists (26.3% women) was 53.7 ± 10.6 years. The panel proposed 34 questions. A consensus was immediately reached for all the proposed questions, 32 were approved and 2 were rejected. CONCLUSIONS: The areas covered by clinical questions included diagnosis of ischemia and infection, treatment of ischemic, neuropathic, and infected ulcers, prevention of foot ulceration, organization and education issues, and surgical management. The PICO presented in this paper are designed to provide indications for healthcare professionals in charge of diabetic foot treatment and prevention, primarily based on clinical needs of people with diabetic foot syndrome and considering the existing organization of health care.

Nickel oxide nanoparticles exposure as a risk factor for male infertility: "In vitro" effects on porcine pre-pubertal Sertoli cells.

Lately, nickel oxide nanoparticles (NiO NPs) have been employed in different industrial and biomedical fields. Several studies have reported that NiO NPs may affect the development of reproductive organs inducing oxidative stress and, resulting in male infertility. We investigated the in vitro effects of NiO NPs on porcine pre-pubertal Sertoli cells (SCs) which undergone acute (24 h) and chronic (from 1 up to 3 weeks) exposure at two subtoxic doses of NiO NPs of 1 µg/ml and 5 µg/ml. After NiO NPs exposure we performed the following analysis: (a) SCs morphological analysis (Light Microscopy); (b) ROS production and oxidative DNA damage, gene expression of antioxidant enzymes (c) SCs functionality (AMH, inhibin B Real-time PCR analysis and ELISA test); (d) apoptosis (WB analysis); (e) pro-inflammatory cytokines (Real-time PCR analysis), and (f) MAPK kinase signaling pathway (WB analysis). We found that the SCs exposed to both subtoxic doses of NiO NPs didn't sustain substantial morphological changes. NiO NPs exposure, at each concentration, reported a marked increase of intracellular ROS at the third week of treatment and DNA damage at all exposure times. We demonstrated, un up-regulation of SOD and HO-1 gene expression, at both concentrations tested. The both subtoxic doses of NiO NPs detected a down-regulation of AMH and inhibin B gene expression and secreted proteins. Only the 5 µg/ml dose induced the activation of caspase-3 at the third week. At the two subtoxic doses of NiO NPs a clear pro-inflammatory response was resulted in an up-regulation of TNF-α and IL-6 in terms of mRNA. Finally, an increased phosphorylation ratio of p-ERK1/2, p-38 and p-AKT was observed up to the third week, at both concentrations. Our results show the negative impact of subtoxic doses NiO NPs chronic exposure on porcine SCs functionality and viability.

Zinc restores functionality in porcine prepubertal Sertoli cells exposed to subtoxic cadmium concentration via regulating the Nrf2 signaling pathway.

Introduction: Among substances released into the environment by anthropogenic activities, the heavy metal cadmium (Cd) is known to induce severe testicular injury causing male subfertility/infertility. Zinc (Zn) is another heavy metal that, unlike Cd, is physiologically present in the testis, being essential for spermatogenesis. We aimed to examine the possibility that 50 µM ZnCl2 could counteract the toxic effects induced by Cd in an in vitro model of porcine prepubertal Sertoli cells (SCs) exposed to both subtoxic (5 µM) and toxic (10 µM) concentrations of CdCl2 for 48 h. Materials and Methods: Apoptosis, cell cycle, and cell functionality were assessed. The gene expression of Nrf2 and its downstream antioxidant enzymes, ERK1/2, and AKT kinase signaling pathways were evaluated. Materials and Results: We found that Zn, in co-treatment with subtoxic and toxic Cd concentration, increased the number of metabolically active SCs compared to Cd exposure alone but restored SC functionality only in co-treatment with subtoxic Cd concentration with respect to subtoxic Cd alone. Exposure of Cd disrupted cell cycle in SCs, and Zn co-treatment was not able to counteract this effect. Cd alone induced SC death through apoptosis and necrosis in a dose-dependent manner, and co-treatment with Zn increased the pro-apoptotic effect of Cd. Subtoxic and toxic Cd exposures activated the Nrf2 signaling pathway by increasing gene expression of Nrf2 and its downstream genes (SOD, HO-1, and GSHPx). Zn co-treatment with subtoxic Cd attenuated upregulation on the Nrf2 system, while with toxic Cd, the effect was more erratic. Studying ERK1/2 and AKT pathways as a target, we found that the phosphorylation ratio of p-ERK1/2 and p-AKT was upregulated by both subtoxic and toxic Cd exposure alone and in co-treatment with Zn. Discussion: Our results suggest that Zn could counteract Cd effects by increasing the number of metabolically active SCs, fully or partially restoring their functionality by modulating Nrf2, ERK1/2, and AKT pathways. Our SC model could be useful to study the effects of early Cd exposure on immature testis, evaluating the possible protective effects of Zn.

Adipokines: A Rainbow of Proteins with Metabolic and Endocrine Functions.

Obesity represents one of the most important health problems worldwide with increasing morbidity and mortality. Widespread prevalence of this disease justifies its actual definition of a "global epidemic". Adipose tissue is nowadays considered a complex organ with lots of endocrine and metabolic functions. In addition to fulfilling its task for energy storage and thermal regulation, by virtue of its constituent white and brown cells, adipose tissue represents, considering its size, the biggest endocrine gland in the body. Both adipocytes and surrounding resident cells (macrophages, endothelial cells and others) produce a huge number of molecules, or adipokines, with endocrine or paracrine functions, that regulate various aspects of metabolism whose clinical relevance is emerging. By balancing pro-inflammatory and anti-inflammatory effects, the adipokines control insulin sensitivity and related glucose metabolism changes, lipid accumulation in the liver and other organs, and finally gonadal function. Collectively, literature data remains cloudy because of still conflicting results of pre-clinical and clinical studies. The aim of this review was to summarize scientific evidence about adipokines' effects on human metabolism, by focusing on their role on either Metabolic Syndrome and NAFLD, or insulin-resistance in pregnancy, or finally, reproductive function disorders.