Rhabdomyosarcoma of Soft Tissues in an Adult Brook Trout (Salvelinus fontinalis).

This report describes a spontaneously arising rhabdomyosarcoma of soft tissues in a brook trout (Salvelinus fontinalis). The lesion was examined by means of histology, immunohistochemistry (IHC) and transmission electron microscopy (TEM). The cross-reactivity of the primary antibodies used in the IHC was investigated in silico using the Protein Blast system. Microscopically, the lesion appeared as a 'small round cell' undifferentiated sarcoma with rare myotube formation. IHC identified expression of sarcomeric actin and vimentin and these molecules showed the highest protein sequence identity. Lower protein sequence identity coincided with negative immunolabelling for desmin, MyoD1, myogenin and CD3. TEM revealed myofibrils, but without a defined sarcomeric architecture. The diagnosis of solid alveolar rhabdomyosarcoma of soft tissues was achieved on the basis of histological and ultrastructural findings.

Relationships between osteoprotegerin, receptor activator of the nuclear factor kB ligand serum levels and carotid intima-media thickness in patients with type 2 diabetes mellitus.

AIM: The aim of this paper was to investigate the association of circulating osteoprotegerin (OPG) and receptor activator of the nuclear factor kB ligand (RANKL) levels with carotid intima-media thickness (CIMT) in type 2 diabetes mellitus (T2DM). METHODS: We performed a cross-sectional community-based study including 40 T2DM postmenopausal women and 40 healthy controls. CIMT was measured by B-mode ultrasound. Serum OPG and RANKL were measured by solid-phase enzyme-linked immunosorbent assay (ELISA). RESULTS: Serum OPG levels were higher in T2DM than in controls (median 2.9 vs 2.0 pmol/liter; P<0.001), significantly associated with CIMT in T2DM (P<0.001). RANKL levels were lower in T2DM than in controls (median 0.45 vs 0.60 pmol/liter; P<0.0001), however no association was found with CIMT. Serum OPG levels were associated with cross-sectional measure of CIMT in T2DM. CONCLUSION: The data would support the role of an increased OPG/RANKL ratio as a possible marker of progression of vascular dysfunction in diabetes.

Bisphosphonates and atherosclerosis.

The relevance of association between osteoporosis and cardiovascular disease in clinical settings, and the evidence of a biological linkage between bone and vascular calcification, encourage the search of drugs that may act as dual-purpose therapies, concordantly enhancing bone density and reducing atherosclerosis. Bisphosphonates (BP) reduce bone resorption and fracture risk, and also seem to have the potential to reduce atherosclerotic process. This unexpected activity is the result of their interference with cholesterol synthesis, inflammatory progression, and oxidative stress. Although most animal studies show a clear anti-atherogenic activity of BP, data in humans are not consistent or conclusive, given the high affinity of BP for bone, which prevents them from accumulating in other tissues at the concentration required to exert a clear pharmacological effect.

L-arginine supplementation normalizes bone turnover and preserves bone mass in streptozotocin-induced diabetic rats.

Osteopenia, an important complication of diabetes mellitus, is responsible of an increase in bone fracture and of a delay in fracture healing. The pathogenesis of this complication is unclear, however decreased availability and synthesis of nitric oxide (NO) may be regarded as a possible cause of disregulation of bone turnover. The aim of our study was to evaluate the effect of streptozotocin (STZ)-induced diabetes in the rat on bone mineral density (BMD) and bone turnover. We also examined whether supplementation of L-arginine (which acts as a NO substrate) could be beneficial for bone. After 6 weeks of STZ treatment, diabetic rats showed a significant decrease of BMD in the whole body, at the spine, at the pelvis, and at the femur. Bone turnover evaluation revealed a significant decrease in the serum levels of osteocalcin (a marker of bone formation), and an increase of the serum levels of the C-terminal telopeptide of type I collagen (RatLaps; a marker of bone resorption). L-arginine supplementation prevented the diabetes-induced reduction of BMD and osteocalcin, and the increase of RatLaps. These pharmacological actions of L-arginine produce a new suggestion that increase of NO synthesis and availability is potentially useful for effective prevention and treatment of osteopenia associated with diabetes.