The role of high-mobility group box protein 1 in collagen antibody-induced arthritis is dependent on vascular endothelial growth factor.

High-mobility group box 1 (HMGB1) has been implicated in angiogenesis and rheumatoid arthritis (RA). The aim of this study was to define more clearly the role of HMGB1 in the synovial angiogenesis and pathogenesis of an immune model of arthritis. BALB/c mice were injected with monoclonal anti-collagen antibody cocktail followed by lipopolysaccharide to induce arthritis. HMGB1 and vascular endothelial growth factor (VEGF) were over-expressed in the areas of the synovium where more inflammation and neoangiogenesis were present. The selective blockade of HMGB1 or VEGF resulted alternatively in a lower severity of arthritis evaluated by the arthritis index. Furthermore, exogenous HMGB1 administration caused a worsening of arthritis, associated with VEGF up-regulation and increased synovial angiogenesis. The selective inhibition of VEGF also resulted in no induction of arthritis in mice receiving exogenous HMGB1. Cytokine enzyme-linked immunosorbent assay (ELISA) analyses performed on peripheral blood and synovial fluid demonstrated a significant reduction of interleukin (IL)-1ß, IL-6 and tumour necrosis factor (TNF)-α in mice where HMGB1 and VEGF pathways were blocked. Interestingly, the selective blockade of HMGB1 and VEGF resulted in an increase of the peripheral IL-17A concentration. The development of arthritis mediated by HMGB1 and the synovial angiogenesis can be blocked by inhibiting the VEGF activity. The proinflammatory and proangiogenic cytokine IL-17A was increased when HMGB1 is inhibited, but the synovial angiogenesis was nevertheless reduced in this model of arthritis. Taken together, these findings shed new light on the role of this nuclear protein in the pathogenesis of arthritis in an RA-like model.

Identification of early predictors of clinical outcomes of COVID-19 outbreak in an Italian single center using a machine-learning approach.

OBJECTIVE: SARS-CoV-2 disease (COVID-19) has become a pandemic disease, determining a public health emergency. The use of artificial intelligence in identifying easily available biomarkers capable of predicting the risk for severe disease may be helpful in guiding clinical decisions. The aim of the study was to investigate the ability of interleukin (IL)-6, troponin I, and D-dimer to identify patients with COVID-19 at risk for intensive care unit (ICU)-admission and death by using a machine-learning predictive model. PATIENTS AND METHODS: Data on demographic characteristics, underlying comorbidities, symptoms, physical and radiological findings, and laboratory tests have been retrospectively collected from electronic medical records of patients admitted to Policlinico A. Gemelli Foundation from March 1, 2020, to September 15, 2020, by using artificial intelligence techniques. RESULTS: From an initial cohort of 425 patients, 146 met the inclusion criteria and were enrolled in the study. The in-hospital mortality rate was 15%, and the ICU admission rate was 41%. Patients who died had higher troponin I (p-value<0.01) and IL-6 values (p-value=0.04), compared to those who survived. Patients admitted to ICU had higher levels of troponin I (p-value<0.01) and IL-6 (p-value<0.01), compared to those not admitted to ICU. Threshold values to predict in-hospital mortality and ICU admission have been identified. IL-6 levels higher than 15.133 ng/L have been associated with a 22.91% risk of in-hospital mortality, and IL-6 levels higher than 25.65 ng/L have been associated with a 56.16% risk of ICU admission. Troponin I levels higher than 12 ng/L have been associated with a 26.76% risk of in-hospital mortality and troponin I levels higher than 12 ng/L have been associated with a 52.11% risk of ICU admission. CONCLUSIONS: Levels of IL-6 and troponin I are associated with poor COVID-19 outcomes. Cut-off values capable of predicting in-hospital mortality and ICU admission have been identified. Building a predictive model using a machine-learning approach may be helpful in supporting clinical decisions in a more precise and personalized way.

Ex vivo-transduced autologous skin fibroblasts expressing human Lim mineralization protein-3 efficiently form new bone in animal models.

Local gene transfer of the human Lim mineralization protein (LMP), a novel intracellular positive regulator of the osteoblast differentiation program, can induce efficient bone formation in rodents. To develop a clinically relevant gene therapy approach to facilitate bone healing, we have used primary dermal fibroblasts transduced ex vivo with Ad.LMP-3 and seeded on a hydroxyapatite/collagen matrix prior to autologous implantation. Here, we demonstrate that genetically modified autologous dermal fibroblasts expressing Ad.LMP-3 are able to induce ectopic bone formation following implantation of the matrix into mouse triceps and paravertebral muscles. Moreover, implantation of the Ad.LMP-3-modified dermal fibroblasts into a rat mandibular bone critical size defect model results in efficient healing, as determined by X-rays, histology and three-dimensional microcomputed tomography (3DmuCT). These results demonstrate the effectiveness of the non-secreted intracellular osteogenic factor LMP-3 in inducing bone formation in vivo. Moreover, the utilization of autologous dermal fibroblasts implanted on a biomaterial represents a promising approach for possible future clinical applications aimed at inducing new bone formation.

A cutaneous infection caused by Brevundimonas vesicularis: a case report.

Brevundimonas vesicularis is a non-fermenting gram-negative bacillus, aerobic and motile. This microorganism is ubiquitous in the environment and has rarely been implicated in human infections. We present the second case of cutaneous infection caused by B. vesicularis in an immunocompetent patient.

Scurvy as cause of purpura in the XXI century: a review on this "ancient" disease.

OBJECTIVE: Scurvy is defined as a deficiency of ascorbic acid, which is an essential exogenous vitamin in humans. Vitamin C is involved in collagen synthesis and its deficit can cause disorders of connective tissue. The most frequent symptoms are weakness, arthralgias, anorexia and depression, commonly associated with follicular hyperkeratosis and perifollicular hemorrhage, with purpura. PATIENTS AND METHODS: A young woman, with a history of malnutrition, manifested purpura and hematoma of the left lower limb. The laboratory tests didn't detect alterations either in coagulation, the platelet count or in the autoimmunity. The total body TC scan didn't show neoplasia or other suspected lesions. Excluding the most important causes of purpura, in consideration of malnutrition, scurvy was suspected. RESULTS: A skin biopsy confirmed the diagnosis. Accordingly to this finding, a treatment with a daily intravenous infusion of vitamin C was started with consequent improvement of hematoma and purpura. CONCLUSIONS: Scurvy is a re-emerging disease, also in western countries. When purpura appears in young adults, scurvy has to be investigated, especially when a history of malnutrition is present. The treatment with vitamin C infusions should be started as soon as possible in order to prevent any complications.

Gene therapy for in vivo bone formation: recent advances.

Gene therapy has developed during the last two decades as a promising strategy for orthopaedics applications, since several different gene transfer techniques proved to be effective, both in vitro and in vivo, for the induction of bone formation. Successful results have been achieved with gene-based bone healing strategies in several preclinical studies, using different animal models. New genes and new viral and non-viral vector constructs have been developed to reduce the risks and safety issues, widening the field of possible applications and improving the potential therapeutical effects. We review the latest gene transfer technologies employed for in vivo bone formation, focusing on the recently identified network of growth factors and genes involved in the modulation of the osteogenetic process and on the variety of vectors utilized for gene delivery.