Adolescent athletes with learning disability display atypical maturational trajectories on concussion baseline testing : Implications based on a Finnish sample

Previous research has reported lower cognitive test scores on baseline testing in athletes reporting multiple previous concussions or a history of learning disability (LD). Age also has an important influence on cognitive performance. While these factors have been considered individually in previous studies, the present study is the first to explore the interaction of age, self-reported LD, and history of concussion on baseline Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT (R)) in a nationwide study of adolescent athletes. ImPACT (R) was administered to 1823 Finnish male ice hockey players (aged 12-21 years old) prior to the 2015-2016 or 2016-2017 playing seasons. Linear regressions and simple slopes analyses were used for clarifying the impact of LD and previous concussion history on maturational trajectories. In comparison to typically developing athletes, athletes with LD had lower neurocognitive scores in all composites and differing maturational trajectory in verbal memory and visual motor speed. The number of previous concussions did not impair neurocognitive performance at baseline assessment. Application of standard age-based norms to adolescent athletes with a history of LD has the potential to negatively skew clinical decision-making. Separate reference values for LD athletes are warranted due to their unique developmental cognitive trajectories. The reference values for the Finnish participants in this study are presented.Peer reviewe

Impaired osteoclast homeostasis in the cystatin B-deficient mouse model of progressive myoclonus epilepsy

Peer reviewe

Unsatisfactory gene transfer into bone-resorbing osteoclasts with liposomal transfection systems

BACKGROUND: Bone-resorbing osteoclasts are multinucleated cells that are formed via fusion of their hematopoietic stem cells. Many of the details of osteoclast formation, activation and motility remain unsolved. Therefore, there is an interest among bone biologists to transfect the terminally differentiated osteoclasts and follow their responses to the transgenes in vitro. Severe difficulties in transfecting the large, adherent osteoclasts have been encountered, however, making the use of modern cell biology tools in osteoclast research challenging. Transfection of mature osteoclasts by non-viral gene transfer systems has not been reported. RESULTS: We have systematically screened the usefulness of several commercial DNA transfection systems in human osteoclasts and their mononuclear precursor cell cultures, and compared transfection efficacy to adenoviral DNA transfection. None of the liposome-based or endosome disruption-inducing systems could induce EGFP-actin expression in terminally differentiated osteoclasts. Instead, a massive cell death by apoptosis was found with all concentrations and liposome/DNA-ratios tested. Best transfection efficiencies were obtained by adenoviral gene delivery. Marginal DNA transfection was obtained by just adding the DNA to the cell culture medium. When bone marrow-derived CD34-positive precursor cells were transfected, some GFP-expression was found at the latest 24 h after transfection. Large numbers of apoptotic cells were found and those cells that remained alive, failed to form osteoclasts when cultured in the presence of RANKL and M-CSF, key regulators of osteoclast formation. In comparison, adenoviral gene delivery resulted in the transfection of CD34-positive cells that remained GFP-positive for up to 5 days and allowed osteoclast formation. CONCLUSION: Osteoclasts and their precursors are sensitive to liposomal transfection systems, which induce osteoclast apoptosis. Gene transfer to mononuclear osteoclast precursors or differentiated osteoclasts was not possible with any of the commercial transfection systems tested. Osteoclasts are non-dividing, adherent cells that are difficult to grow as confluent cultures, which may explain problems with transfection reagents. Large numbers of α(v)β(3 )integrin on the osteoclast surface allows adenovirus endocytosis and infection proceeds in dividing and non-dividing cells efficiently. Viral gene delivery is therefore currently the method of choice for osteoclast transfection

Noninvasive and Quantitative Monitoring of the Distributions and Kinetics of MicroRNA-Targeting Molecules in Vivo by Positron Emission Tomography

MicroRNAs (miRNAs) are endogenous, small, noncoding ribonucleic acids (RNAs) that bind to the 3' untranslated regions of messenger RNAs (mRNAs) and induce translational repression or mRNA degradation. Although numerous studies have reported that miRNAs are of potential use for disease diagnostics and gene therapy, little is known about their fates in vivo. This study elucidated the whole-body distributions and kinetics of intravenously administered miRNA-targeting molecules in vivo by positron emission tomography (PET) imaging. A 22-mer sequence targeting miR-1513 was conjugated with three different chelators and labeled with gallium-68 (Ga-68). These tracers were compared with a scrambled 22-mer sequence; 22-mer with two single base substitutions; anti-miR-34 22-mer; hexathymidylate (T-6), a 6-mer sequence; and an unconjugated chelator. miR-15b was chosen as a target because it is important for bone remodeling. All three Ga-68-labeled anti-miR-15b molecules had similar biodistributions and kinetics, and they all accumulated in the bones, kidneys, and liver. The bone accumulation of these tracers was the highest in the epiphyses of long tubular bones, maxilla, and mandible. By contrast, the scrambled 22-mer sequence, the 6-mer, and the unconjugated chelator did not accumulate in bones. PET imaging successfully elucidated the distributions and kinetics of Ga-68-labeled chelated miRNA-targeting molecules in vivo. This approach is potentially useful to evaluate new miRNA-based drugs

Inhibition of the osteoclast V-ATPase by small interfering RNAs

AbstractThe multisubunit enzyme V-ATPase harbours isoforms of individual subunits. a3 is one of four 116kDa subunit a isoforms, and it is crucial for bone resorption. We used small interfering RNA (siRNA) molecules to knock down a3 in rat osteoclast cultures. Labeled siRNA-molecules entered osteoclasts via endocytosis and knocked down the a3 mRNA. Bone resorption was decreased in siRNA-treated samples due to decreased acidification and osteoclast inactivation. Expression of a1 did not respond to decreased a3 levels, suggesting that a1 does not compensate for a3 in osteoclast cultures. Subunit a3 is thus an interesting target for novel nucleic acid therapy

Calcific spurs at the insertion of the Achilles tendon: a clinical and histological study

In active people, insertional calcific tendinopathy (CT) of the Achilles tendon is rare. We evaluated the results of surgical treatment for Achilles tendon CT and analyzed post-surgery Achilles tendon histological features. The study included 36 operations in 34 patients. Twenty-eight (78%) cases had a resection of a Haglund’s deformity performed. The mean age of the patients was 42 years (range=23 to 68). Thirteen of the patients were professional athletes and 20 recreational athletes. In twenty-five (69%) cases, the result of surgery was rated good, in nine cases (25%) moderate and in two (6%) cases poor. The mean age of those with a good result was 10 years lower (40 versus 50 years) than those with a moderate result (p=0.0239). Higher athletic activity was also related to a better outcome (p=0.0205). Histology samples showed fast remodellation and stem-cell activation. Surgery seemed to result in a good outcome in patients with or without a Haglund’s deformity which failed conservative treatmen

Solid-Supported NOTA and DOTA Chelators Useful for the Synthesis of 3′-Radiometalated Oligonucleotides

Esterified precursors of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA; <b>18</b>) and 1,4,7-triazacyclononane-1,4,7-trisacetic acid (NOTA; <b>17</b>,<b>19</b>) ligands bearing a dimethoxytritylated hydroxyl side arm were prepared and immobilized via an ester linkage to long chain alkyl amine derivatized controlled pore glass (LCAA-CPG). Oligonucleotide chains were then assembled on the hydroxyl function and conjugates were released and deprotected by a two-step cleavage with aqueous alkali and ammonia. The 3′-DOTA and 3′-NOTA conjugated oligonucleotides were converted to ⁶⁸Ga chelates by a brief treatment with [⁶⁸Ga]­Cl₃ at elevated temperature. Applicability of the conjugates for <i>in vivo</i> imaging with positron emission tomography (PET) was verified