Effects of androgens on cultured cells derived from canine anterior cruciate ligament

Biomechanical characterization of human temporal muscle fascia in uniaxial tensile tests for graft purposes in duraplasty

The human temporal muscle fascia (TMF) is used frequently as a graft material for duraplasty. Encompassing biomechanical analyses of TMF are lacking, impeding a well-grounded biomechanical comparison of the TMF to other graft materials used for duraplasty, including the dura mater itself. In this study, we investigated the biomechanical properties of 74 human TMF samples in comparison to an age-matched group of dura mater samples. The TMF showed an elastic modulus of 36 ± 19 MPa, an ultimate tensile strength of 3.6 ± 1.7 MPa, a maximum force of 16 ± 8 N, a maximum strain of 13 ± 4% and a strain at failure of 17 ± 6%. Post-mortem interval correlated weakly with elastic modulus (r = 0.255, p = 0.048) and the strain at failure (r =  − 0.306, p = 0.022) for TMF. The age of the donors did not reveal significant correlations to the TMF mechanical parameters. Compared to the dura mater, the here investigated TMF showed a significantly lower elastic modulus and ultimate tensile strength, but a larger strain at failure. The human TMF with a post-mortem interval of up to 146 h may be considered a mechanically suitable graft material for duraplasty when stored at a temperature of 4 °C.

The influence of sex hormones on anterior cruciate ligament ruptures in males

PURPOSE

The purpose of this study is to determine the difference in the concentrations of testosterone, 17-β estradiol and progesterone between male patients with and without ACL rupture, as well as the possible effect of these hormones on generalized joint laxity.

METHODS

Male subjects with non-contact knee joint injury were included in this study. Two groups were formed: the examined group, consisting of subjects with ACL rupture and the control group consisting of patients without ACL rupture. After this, the patients from these two groups were paired off on the basis of three factors, level of professional involvement in sports (including the type of sports activity), left or right side of the body and the age of the subjects. In the end, there were 29 pairs (58 subjects). The concentration of sex hormones was determined from saliva specimens with the aid of the Salimetrics enzyme immunoassay. The testing of generalized joint laxity was performed with the aid of the "laxity score" according to Beighton et al.

RESULTS

Subjects with ACL rupture have highly statistically significantly greater concentrations of testosterone (p < 0.01), statistically significantly greater concentrations of 17-β estradiol (p < 0.05), and a highly statistically significantly greater generalized joint laxity score than subjects with an intact ACL (p < 0.01).

CONCLUSION

Increased concentrations of testosterone or 17-β estradiol may be a risk factor leading to ACL rupture. Also, generalized joint laxity may be a factor leading to ACL rupture, but none of the monitored hormones can be set down as the cause of its existence. Young male athletes with higher concentrations of testosterone and greater hyperelasticity should plan preventive programs of physiotherapy for ACL preservation since they present a vulnerable group susceptible to ACL rupture.

LEVEL OF EVIDENCE

Diagnostic study, Level II.

Differential responses to steroid hormones in fibroblasts from the vocal fold, trachea, and esophagus

There is accumulating evidence that fibroblasts are target cells for steroids such as sex hormones and corticoids. The characteristics of fibroblasts vary among tissues and organs. Our aim in this study is to examine differences in responses to steroid hormones among fibroblasts from different cervicothoracic regions. We compared the actions of steroid hormones on cultured fibroblasts from the vocal folds, which are considered to be the primary target of steroid hormones, and the trachea and esophagus in adult male rats. Expression of steroid hormone receptors (androgen receptor, estrogen receptor α, and glucocorticoid receptor) was identified by immunofluorescence histochemistry. Androgen receptor was much more frequently expressed in fibroblasts from the vocal fold than in those from the trachea and esophagus. Cell proliferation analysis showed that administration of testosterone, estradiol, or corticosterone suppressed growth of all 3 types of fibroblasts. However, mRNA expression for extracellular matrix-associated genes, including procollagen I and III and elastin, and hyaluronic acid synthase I was elevated only by addition of testosterone to fibroblasts from the vocal fold. These results indicate that each steroid hormone exerts region-specific effects on cervicothoracic fibroblasts with different properties through binding to specific receptors.

Pachydermodactyly: a review

Synovitis is the characteristic feature of inflammatory joint disease. If synovitis is localized to interphalangeal joints, rheumatoid arthritis, psoriatic arthritis, and juvenile idiopathic arthritis are among the most common differential diagnoses. The absence of pain, tenderness, and limitation of function despite progressive swelling of proximal interphalangeal joints suggests an alternative diagnosis, for example pachydermodactyly (PDD). This is a benign disease, associated with asymptomatic, progressive swelling of periarticular soft tissue, which usually occurs in young males. PDD is probably the result of repetitive mechanical stimulation. One hundred and twenty-one cases have been reported in the literature. Some of these were initially misdiagnosed and treated for inflammatory arthritis. We provide a comprehensive review of the literature on pachydermodactyly to promote awareness of this rare but important differential diagnosis of arthritis.