The alizarin red S assay is considered the gold standard for quantification of osteoblast mineralization and is thus widely used among scientists. However, there are several restrictions to this method, e.g., moderate sensitivity makes it difficult to uncover slight but significant effects of potentially clinically relevant substances. Therefore, an adaptation of the staining method is appropriate and might be obtained by increasing the mineralization ability of osteoblasts. In this study, cell culture experiments with human (SaOs-2) and murine (MC3T3-E1) osteoblasts were performed under the addition of increasing concentrations of calcium chloride (1, 2.5, 5, and 10 mM) or calcitonin (1, 2.5, 5, and 10 nM). After three or four weeks, the mineralization matrix was stained with alizarin red S and the concentration was quantified photometrically. Only calcium chloride was able to significantly increase mineralization, and therefore enhanced the sensitivity of the alizarin red S staining in a dose-dependent manner in both osteoblastic cell lines as well as independent of the cell culture well surface area. This cost- and time-efficient optimization enables a more sensitive analysis of potentially clinically relevant substances in future bone research.

Objective: To review the current knowledge on bone health in patients with hemophilia A and the underlying pathogenetic mechanisms.Data Sources: Original research articles, meta-analyses, and scientific reviews.Data Synthesis: Already in childhood, patients with hemophilia A are prone to low bone mineral density, leading to osteopenia and/or osteoporosis. Initially associated with the life style of hemophilia, today we are faced with accumulating evidence that coagulation factor VIII is involved directly or indirectly in bone physiology.Conclusion: Understanding the role of factor VIII and the mechanisms of decreased bone mineral density in hemophilia A is critically important, especially as non-factor replacement therapies are available, and treatment decisions potentially impact bone health.

Whether and to which extent placebo treatment in double-blinded randomized controlled clinical trials is effective in chronic arthritic diseases has not been studied before. Therefore, a systematic literature search was undertaken to detect eligible trials. Demographic data of the placebo groups as well as concomitant and previous disease outcomes were collected. Analyses of significant bivariate correlations and linear regression between clinical endpoints and characteristics of the placebo groups were performed. A total of 152 double-blinded randomized controlled studies, including 21,616 participants in the placebo groups, was analyzed. The results of bivariate correlations and linear regressions revealed significant positive associations between responses in the placebo groups and the following factors: (i) naïvety of previous treatment and (ii) early stage of disease. In addition to the clinical relevance, the results support the importance of the placebo effect on study size calculations, and will allow an optimized calculation of patients’ numbers for early placebo-controlled trials conducted in patients with chronic arthritic diseases.

Background/Objectives: Early fluid resuscitation is a cornerstone of trauma care, but the relationship between resuscitation strategies and acute kidney injury (AKI) remains insufficiently characterized. This study aimed to evaluate whether administration of 4% succinylated gelatin is associated with the development of AKI in critically ill trauma patients during the first seven days of intensive care unit (ICU) treatment. Methods: We conducted an observational retrospective single-center cohort study including 215 adult trauma patients admitted to the ICU at a tertiary care center between 2015 and 2020. Gelatin exposure, kidney function, and clinical outcomes were assessed from the pre-ICU phase through the first ICU week. The primary outcome was the development of AKI, at stage ≥ 2 of the Kidney Disease: Improving Global Outcomes (KDIGO) staging. We used mixed-effects models, competing-risk analyses, correlation analyses and exploratory unsupervised clustering to explore associations between gelatin use and renal outcomes. Results: AKI occurred in 17% of patients and was associated with older age, higher Simplified Acute Physiology Score 3 (SAPS3), pre-existing comorbidities, and early signs of hemodynamic and metabolic compromise. Gelatin doses of ≥10 mL/kg/day were not associated with a consistent rise in serum creatinine or progression of AKI over time. Multivariable regression models revealed no independent association between gelatin and worsening AKI. Instead, KDIGO stage worsening was primarily associated with AKI present at ICU admission and with crystalloid volume. Clustering analysis identified a high-risk phenotype with increased gelatin exposure, but this cluster also showed pronounced shock and inflammation, suggesting confounding by indication. In a competing-risk analysis, gelatin was not associated with new-onset AKI, whereas higher gelatin doses were associated with a lower rate of ICU discharge. Conclusions: In this retrospective cohort of critically ill trauma patients, succinylated gelatin administration showed no statistically significant association with KDIGO-defined AKI progression across unadjusted and adjusted models. Gelatin doses of ≥10 mL/kg/day were more frequently administered in patients with greater hemodynamic instability, suggesting that gelatin use primarily reflected underlying illness severity rather than acting as a direct nephrotoxic agent. These findings provide no evidence of an independent nephrotoxic effect of gelatin when used as part of balanced trauma resuscitation strategies.

Background/Objectives: Hemophilia A is associated with frequent bleeding episodes, joint damage, and reduced bone mineral density (BMD). The role of coagulation factors and inflammatory cytokines on bone metabolism, particularly on osteoblast function, is of increasing interest. However, significant inter-species differences in bone remodeling raise concerns about the translatability of findings from murine models to human systems. This study aims to investigate the effects of human coagulation factors and cytokines on bone formation, focusing on inter-species differences in the cell viability and mineralization of murine and human osteoblasts. Methods: Murine MC3T3-E1 and human SaOs-2 osteoblasts were cultured in osteoblast differentiation medium supplemented with various coagulation factors (FVIII, vWF, vWF-FVIII, FIX, FX, thrombin, and FVIII-thrombin) or cytokines (IL-6, TNF-α). Cell viability was assessed at both two-week and three-week time points using the CCK-8 assay, and mineralization was evaluated via Alizarin red S staining. Results: Coagulation factors significantly enhanced cell viability in human osteoblasts but had no effects on the murine counterpart. FX inhibited mineralization in human cells, while murine cells showed no significant changes. TNF-α stimulated mineralization in murine osteoblasts but inhibited it in human cells, highlighting species-specific responses to inflammatory cytokines. Similar trends in response patterns were observed at two and three weeks, with greater consistency at the later time point. Conclusions: These findings reveal critical inter-species differences in osteoblast responses to coagulation factors and cytokines, raising questions about the validity of using murine models to study human bone metabolism. Future research must account for these differences to ensure that preclinical models accurately reflect human pathophysiology, particularly in the context of hemophilia A.