Long-term outcomes after repair of recurrent post-traumatic anterior shoulder instability: comparison of arthroscopic transglenoid suture and open Bankart reconstruction

Purpose  

The purpose of this study is to report long-term outcomes of the arthroscopic modified Caspari technique compared to an open capsular shift surgery to treat post-traumatic anterior shoulder recurrent instability. The hypothesis was that the open surgery group would show higher degenerative changes than to the modified Caspari technique group after a follow-up from 10 to 17 years.     

Betaine, dimethyl sulfoxide, and 7-deaza-dGTP, a powerful mixture for amplification of GC-rich DNA sequences

Currently, polymerase chain reaction is the most used technique in many laboratories for either diagnostic or molecular biology purposes. Despite the large number of DNA sequences that can be easily analyzed, some GC-rich sequences are refractory to amplification due to the formation of secondary intramolecular structures. To overcome this problem, several molecules have been described to improve polymerization. Here we show that a combination of three additives--betaine, dimethyl sulfoxide, and 7-deaza-dGTP--was essential to achieve amplification of DNA sequences of three disease genes showing a GC content ranging from 67 to 79%.     

AIRE gene polymorphisms in systemic sclerosis associated with autoimmune thyroiditis

Mutations in the autoimmune regulator (AIRE) gene are responsible for autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED). Systemic sclerosis (SSc) is a non-organ-specific autoimmune disease mainly characterized by cutaneous involvement, that is frequently associated with other autoimmune manifestations common to APECED. Nineteen SSc patients, 22 patients affected by SSc associated with autoimmune thyroiditis, and 100 healthy controls were analyzed. We identified 11 AIRE gene variants, one of which has never previously been described. Intronic polymorphism G11107A was significantly correlated to SSc/thyroiditis. Data show that variants of the AIRE gene might be correlated to different clinical manifestations in SSc patients.     

Overexpression of the C-type natriuretic peptide (CNP) is associated with overgrowth and bone anomalies in an individual with balanced t(2;7) translocation

Longitudinal bone growth is determined by the process of endochondral ossification in the cartilaginous growth plate, which is located at both ends of vertebrae and long bones and involves many systemic hormones and local regulators. We report the molecular characterization of a de novo balanced t(2;7)(q37.1;q21.3) translocation in a young female with Marfanoid habitus and skeletal anomalies. The translocation was characterized by fluorescence in situ hybridization (FISH), checked for other abnormalities by array-comparative genomic hybridization (CGH), and finally, the breakpoints were cloned, sequenced, and compared. Biochemical dosage was applied to study the possible mechanisms that may cause the proposita's phenotype. The breakpoint on chromosome 2 disrupts the hypothetical gene MGC42174 (HUGO-approved symbol DIS3L2) and is located in the proximity of the NPPC gene coding for C-type natriuretic peptide (CNP), a molecule that regulates endochondral bone growth. CNP plasma concentration was doubled in the proband compared to five normal controls, while NPPC was substantially overexpressed in her fibroblasts. A transgenic mouse generated to target NPPC overexpression in bone showed a phenotype highly reminiscent of the patient's phenotype. The breakpoint on chromosome 7 is localized proximally at about 75 kb from the COL1A2 gene. The COL1A2 allele on the derivative chromosome was strongly underexpressed in fibroblasts, but total collagen was not significantly different from controls. Several evidences support the conclusion that the proband's abnormal phenotype is associated with C-type natriuretic peptide overexpression.     

Mutational analysis of the ACVR1 gene in Italian patients affected with fibrodysplasia ossificans progressiva: confirmations and advancements

Fibrodysplasia ossificans progressiva (FOP, MIM 135100) is a rare genetic disorder characterized by congenital great toe malformations and progressive heterotopic ossification transforming skeletal muscles and connective tissues to bone following a well-defined anatomic pattern of progression. Recently, FOP has been associated with a specific mutation of ACVR1, the gene coding for a bone morphogenetic protein type I receptor. The identification of ACVR1 as the causative gene for FOP now allows the genetic screening of FOP patients to identify the frequency of the identified recurrent ACVR1 mutation and to investigate genetic variability that may be associated with this severely debilitating disease. We report the screening for mutations in the ACVR1 gene carried out in a cohort of 17 Italian patients. Fifteen of these displayed the previously described c.617G>A mutation, leading to the R206H substitution in the GS domain of the ACVR1 receptor. In two patients, we found a novel mutation c.774G>C, leading to the R258S substitution in the kinase domain of the ACVR1 receptor. In the three-dimensional model of protein structure, R258 maps in close proximity to the GS domain, a key regulator of ACVR1 activity, where R206 is located. The GS domain is known to bind the regulatory protein FKBP12 and to undergo multiple phosphorylation events that trigger a signaling cascade inside the cell. The novel amino-acid substitution is predicted to influence either the conformation/stability of the GS region or the binding affinity with FKBP12, resulting in a less stringent inhibitory control on the ACVR1 kinase activity.