ABSTRACT
<p><b>OBJECTIVE</b>To investigate the morphological changes of the roof of the subacromial bursa (SAB) and its involvement extent after rotator cuff tear.</p><p><b>METHODS</b>In the experimental group, the roof of SAB was obtained from 30 cases of rotator cuff tear both at the tear site and a site 2.5-3.0 cm distal to the tear site during rotator cuff repair. In the control group, the roof of SAB was obtained from the exposed site of recurrently dislocated shoulder or fractured humeral shaft of 8 cases. The specimens were stained with hematoxylin and eosin and observed under a transmission electron microscope. The cell number was quantitated through counting the blue-stained nucleus in SAB with a computer image analysis system.</p><p><b>RESULTS</b>The number of cells increased significantly in the roof of SAB in the experimental group compared with that of the control group. However, no difference of the bursal reaction was found among the type of rotator cuff tear, the bursa thickness and the presence of fluid in the bursa. The great majority of cells were type B cells observed under the transmission electron microscope.</p><p><b>CONCLUSIONS</b>The increase in cell number in the roof of SAB in the experimental group is a reactive increase rather than an inflammatory process and the involvement of SAB is not limited in extent. The change of the roof of SAB is a secondary reaction to the rotator cuff tear.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Analysis of Variance , Bursa, Synovial , Pathology , Inflammation , Microscopy, Electron , Rotator Cuff InjuriesABSTRACT
<p><b>OBJECTIVE</b>To investigate the expression of neurotrophin-3 (NT-3) gene in Schwann cells of rat sciatic nerve introduced by an adenovirus vector in vivo.</p><p><b>METHODS</b>A recombinant adenovirus vector for NT-3 (Ad-NT-3) was propagated in 293 packaging cells and titered with tissue culture infectious dose(50) (TCID(50)). Ad-NT-3 was injected directly into the rat sciatic nerve after transection and immediate repair. Immunohistochemical staining was employed to determine the expression of NT-3 in Schwann cells in rat sciatic nerve and the expressive intensity of the tissue slices of the sciatic nerve was measured with LEICA M550 image analysis system.</p><p><b>RESULTS</b>On the 2nd day after injection of Ad-NT-3, positive stain in the Schwann cells was apparent in the vicinity of anastomosis. NT-3 expression increased significantly on the 7th day (P<0.01) and then decreased 14-28 days after injection (P<0.01). There was no significant difference of NT-3 expression between the 14th and 28th day groups (P<0.05). Compared with the 2nd day group, the 14th and 28th day groups still maintained a relatively high level of NT-3 (P<0.01). Intact and repaired nerves, which were injected with adenovirus encoding LacZ genes (Ad-LacZ) or physiological saline served as controls, showed no NT-3-positive Schwann cells.</p><p><b>CONCLUSIONS</b>An adenovirus vector can be used to induce efficiently the expression of NT-3 gene in Schwann cells of rat peripheral nerves following nerve injury and repair, which suggests that neurotrophic factors can be introduced into Schwann cells with an adenovirus vector to promote peripheral nerve regeneration.</p>