Injury characteristics of young elite inline speed skaters: A one season retrospective study.

OBJECTIVES: Determining the rate of injuries related to a certain sport is accepted as the primary step toward designing, implementing and evaluating injury prevention programs. This observational and retrospective study was to examine the injuries sustained by elite young Spanish inline speed skaters during a season. METHODS: Athletes participating in the national championship (n = 80) were surveyed via an anonymous online questionnaire to screen for injury characteristics: incidence, location, and tissue affected; plus training information and demographics. RESULTS: A total of 52 injuries were recorded across 33,351 hours of exposure, which gives a rate of 1.65/1,000 h. The lower body comprised 79% of the total amount of injuries (1.3/1000 h), and the main areas affected were the thigh and foot, accounting for 25% and 19.2% of the recorded injuries, respectively. Musculotendinous injuries were the most frequent, with an incidence of 0.92/1000 h. No significant gender differences were observed for any of the variables studied. CONCLUSION: Speed skating can be considered a low injury rate sport based on our findings. The risk of sustaining an injury was independent of gender, age, and BMI.

A global health model integrating psychological variables involved in cancer through a longitudinal study.

Objective: The literature has shown the relevance of certain psychological variables in adjustment to cancer. However, there is a great variability, and these features could be modified through the disease process. The aim of this study is to provide an integrated and global perspective of the importance of variables such as coping, resilience, emotional control, social support, affect, and others in cancer patients through a longitudinal study, with the objective of exploring their associations and underlying interactions. Methods: The sample was composed of 71 people diagnosed with cancer who were attending psychological support at the Spanish Association Against Cancer (Biscay). We assessed the following variables in two periods of 6 months: perceived stress (PSS), emotional control (CECS), resilience (CD-RISC), coping strategies (CERQ), personality (NEOFFI), social support (MOSS), affect (PANAS), emotional distress (GHQ), quality of life (SF-12) and visual-analogic scales (EVA). Results: Results showed predictive effects of perceived stress on physical health perception (ß = -0.22; t = -3.26; p = 0.002). Mental health perception was influenced by almost all the psychological variables. Consciousness at baseline (ßCo = 0.15; p = 0.003), change in Extraversion (ßEx = 0.16; p = 0.001) and Resilience (ßRe = 0.15; p = 0.002) had significant effects on perceived mental health. Conclusion: This study provides a global health model that integrates and explores associations between psychological variables related to cancer disease. This information could be useful for guiding personalized psychotherapeutic interventions, with the aim of increasing adjustment to disease.

CD38 Deficiency Ameliorates Chronic Graft-Versus-Host Disease Murine Lupus via a B-Cell-Dependent Mechanism.

The absence of the mouse cell surface receptor CD38 in Cd38-/- mice suggests that this receptor acts as a positive regulator of inflammatory and autoimmune responses. Here, we report that, in the context of the chronic graft-versus-host disease (cGVHD) lupus inducible model, the transfer of B6.C-H2bm12/KhEg(bm12) spleen cells into co-isogenic Cd38-/- B6 mice causes milder lupus-like autoimmunity with lower levels of anti-ssDNA autoantibodies than the transfer of bm12 spleen cells into WT B6 mice. In addition, significantly lower percentages of Tfh cells, as well as GC B cells, plasma cells, and T-bet+CD11chi B cells, were observed in Cd38-/- mice than in WT mice, while the expansion of Treg cells and Tfr cells was normal, suggesting that the ability of Cd38-/- B cells to respond to allogeneic help from bm12 CD4+ T cells is greatly diminished. The frequencies of T-bet+CD11chi B cells, which are considered the precursors of the autoantibody-secreting cells, correlate with anti-ssDNA autoantibody serum levels, IL-27, and sCD40L. Proteomics profiling of the spleens from WT cGVHD mice reflects a STAT1-driven type I IFN signature, which is absent in Cd38-/- cGVHD mice. Kidney, spleen, and liver inflammation was mild and resolved faster in Cd38-/- cGVHD mice than in WT cGVHD mice. We conclude that CD38 in B cells functions as a modulator receptor that controls autoimmune responses.

Mass spectrometric approach for the analysis of the hard protein corona of nanoparticles in living cells.

The diagnostic and therapeutic application of nanoparticles requires comprehensive knowledge of their interaction with the biomolecular surroundings. The formation of the protein corona on nanoparticles that were internalized by living cells is yet to be understood. In this study, we present a robust approach for the electrophoretic and mass spectrometric analysis of the hard protein corona composition formed in living cells on ~30 nm citrate-stabilized gold nanoparticles, i.e., the proteins with the highest affinity towards the gold nanoparticle surface. The gold nanoparticles were internalized by MCF-7 cells for 24 h followed by the extraction of the hard protein corona­gold nanoparticle bioconjugates from living cell cultures. The extracted proteins were then separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and analyzed by ESI-Q-TOF-MS, which allowed to identify 108 hard corona proteins. The experiments were repeated with J774 macrophage cells with incubation times of 1.5 h, 3 h, 6 h, and 24 h, and the results showed that the hard protein corona remained unchanged over time. Therefore, the proposed experimental approach proved to be a valuable tool for identifying hard corona proteins of nanoparticles internalized by living cells.

Complementary techniques (spICP-MS, TEM, and HPLC-ICP-MS) reveal the degradation of 40 nm citrate-stabilized Au nanoparticles in rat liver after intraperitoneal injection.

BACKGROUND: Due to the increased use of engineered nanoparticles (NPs), their tracing in environmental and biological systems is of utmost importance. Besides their accumulation within a biological specimen, little is known about their degradation and transformation into corresponding low-molecular species that might influence any toxicological impact. ANALYTICAL METHODS: Wistar rats underwent intraperitoneal injections of 40 nm citrate-stabilized gold nanoparticles. Different liver samples were analysed for the occurrence of nanoparticles and potential degradation products by means of spICP-MS, TEM and HPLC-ICP-MS. MAIN FINDINGS: Studies using spICP-MS revealed the presence of the originally administrated Au NPs (40 nm diameter) and some evidences of other Au-containing species due to the increased background signal. Images obtained by transmission electron microscopy (TEM) showed the predominant presence of particles of significantly smaller diameter (6 ± 2 nm). As complementary method, HPLC-ICP-MS confirmed the presence of both particle types indicating a degradation of the Au NPs accompanied by detection of low-molecular Au species. CONCLUSIONS: This study underlines that degradation of gold nanoparticles to low-molecular gold species might have to be taken into account in future for studies on their toxicological behaviour and their potential use in clinical applications.

Determination and speciation of cadmium in microcosms with Bunodosoma caissarum and Perna perna using isotopically enriched 116Cd.

The study of the uptake and distribution of elements in marine environments is of great interest for understanding their pathways and accumulation. Here, we investigated in laboratory experiments the accumulation behavior of Cd in the sea anemone Bunodosoma caissarum and the mussel Perna perna. Specimens were incubated with isotopically enriched 116Cd in aquariums. Cd concentrations in the seawater and in the tissues of B. caissarum and P. perna were followed by inductively coupled plasma-mass spectrometry (ICP-MS) by means of isotope dilution analysis. Bioconcentration factors for B. caissarum and P. perna exposed to 0.9µg·L-1 of 116Cd were determined to be 80.5 and 850, respectively. P. perna specimens exposed to 4.5µg·L-1 of 116Cd reached 530. Cytosolic proteins associated with Cd from the tissues were extracted and further analyzed by size-exclusion chromatography coupled to ICP-MS. Cd accumulation could be detected in both organisms ranging from high-molecular to low-molecular species.

Complementary mass spectrometric techniques for the quantification of the protein corona: a case study on gold nanoparticles and human serum proteins.

Once nanoparticles enter a biological system, it is known that their surface is instantly covered by the biomolecules present with preference to proteins. This protein corona has been a subject of numerous studies in order to reveal its composition. Besides that, growing interest exists in its quantitative determination in order to gain a deeper insight into the nature of these nanoparticle-protein bioconjugates. Only a few analytical methods are available nowadays, so the aim of this study is to provide a reliable and alternative methodology for the quantification of the protein corona. The suggested approach is based on the assumption that the total protein content within the corona can be correlated to its sulfur concentration due to the presence of cysteine and methionine as sulfur-containing amino acids. Once the most abundant proteins had been identified with the use of gel electrophoresis with subsequent peptide analysis by electrospray ionization-tandem mass spectrometry (ESI-MS/MS), the isolated nanoparticle-protein conjugates were subjected to total analysis of sulfur and the corresponding metal being present in the nanoparticles by inductively coupled plasma-mass spectrometry (ICP-MS). The concept is exemplarily demonstrated on citrate-stabilized gold nanoparticles (GNPs) incubated with human serum. Two different purification procedures were tested in order to isolate the sought bioconjugates. 26 most abundant proteins could be identified and an average of approximately 40 S atoms per protein was calculated and used for further studies. ICP-MS analyses of S/Au ratios served for the quantification of the protein corona revealing an absolute number of proteins bound to the incubated GNPs. Two main results could be obtained for this specific system under the chosen experimental conditions: the number of proteins per GNP decreased with their size from 10 nm to 60 nm and the obtained values suggested that the protein corona in this specific case was theoretically formed either as a monolayer (60 nm GNPs) or as a multilayer (5-7 protein layers per 10 nm GNP). Studies with bovine serum albumin (BSA) as the model protein showed similar results.

Synthesis, purification and mass spectrometric characterisation of a fluorescent Au9@BSA nanocluster and its enzymatic digestion by trypsin.

Nanoclusters of noble metals like Ag and Au have attracted great attention as they form a missing link between isolated metal atoms and nanoparticles. Their particular properties like luminescence in the visible range and nontoxicity make them attractive for bioimaging and biolabelling purposes, especially with use of proteins as stabilising agents. In this context, this study intends the synthesis of a specific Au nanocluster covered by bovine serum albumin (BSA). It is shown that size-exclusion chromatography is feasible for the purification and isolation of the nanocluster. A mass spectrometric characterisation, preferably by ESI-MS, indicates the presence of an Au9@BSA nanocluster. Enzymatic digestion of the nanocluster with trypsin results in a significant increase of the fluorescence intensity at 650 and 710 nm, whereas complementary MALDI-MS studies are presented for the identification of generated peptides and show a distinctive pattern in comparison to the pure protein. It can be concluded that Au9@BSA might be, in future, an interesting candidate for in vitro studies of protease activities.