Monocyte diapedesis through an in vitro vessel wall construct: inhibition with monoclonal antibodies to thrombospondin

Human peripheral blood monocytes were examined for migration across an endothelial cell monolayer in an in vitro vessel wall construct. Few monocytes invaded in the absence of a chemotactic gradient, despite significant adhesion to the endothelial monolayer. However, the addition of zymosan-activated human plasma to the lower compartment, to create a chemotactic gradient across the vessel wall, resulted in significantly enhanced monocyte migration. Pretreatment of the monocytes with monoclonal antibodies to thrombospondin (TSP) dramatically inhibited monocyte diapedesis into the vessel wall. The same treatment inhibited monocyte adhesion to endothelial cells in two-dimensional monolayer cultures as well as in vessel wall constructs (no chemotactic gradient). Of interest, however, the monoclonal antibodies had no inhibitory effect on monocyte migration into collagen gels devoid of endothelial cells in response to the same chemotactic gradient, suggesting the importance of TSP in monocyte-endothelial cell interactions. Monoclonal antibodies to fibronectin and normal mouse immunoglobulin G did not inhibit migration in this model of a vessel wall. Furthermore, monoclonal antibodies to TSP showed no inhibition of human peripheral blood neutrophil migration. Previous studies have shown that monocytes synthesize TSP and express this moiety on their surface. The present data suggest that monocytes may utilize TSP to interact with endothelial cells lining the vessel wall during diapedesis.     

Anthropometric data for describing the kinematics of the human hand.

The major goal of this investigation was to collect statistically-based anthropometry describing the kinematics of the human hand and to model this anthropometry as a function of external hand measurements, so that it may be predicted noninvasively. Joint centres were anatomically estimated as the centre of curvature of the head of the bone proximal to the given joint. Joint centres determined using Reuleaux's method for PIP and DIP were within 1.4 mm of this anatomical estimate. Models using bone length as the independent variable explain more than 97% of the variability in the anatomically estimated joint centre position along the mid-line of the bone. Models for estimating the lengths of the kinematic segments using external hand length as the independent variable account for between 49 and 99% of the variability in segment length. Models for estimating the axial location of the finger MCP and thumb CMC joints with respect to the distal wrist crease using external hand length as the independent variable account for between 82 and 96% of the variability in these locations. Models for estimating the radio-ulnar location of the finger MCP and thumb CMC joints with respect to the long axis of the third metacarpal using external hand breadth as the independent variable account for between 30 and 74% of the variability in these locations.     

Correlative MR-anatomic study of the median nerve

OBJECTIVE: The purpose of our study was to evaluate the effectiveness of MR imaging for showing the intrinsic anatomy of a peripheral nerve. Cadaver wrist specimens that included the median nerve were imaged with MR imaging at 3 T, then sectioned, stained, and inspected grossly and microscopically. The size, shape, and signal intensity of the sheath and axonal structures in the median nerve were identified in MR images by comparison with anatomic sections. CONCLUSION: This study suggests that MR imaging with sufficiently high-resolution techniques shows the internal structure of peripheral nerves. These results suggest that MR imaging may be a means to distinguish neuritis, tumor, degeneration, or fatty proliferation in a peripheral nerve and to evaluate the nerve before microsurgical anastomosis.     

Expression of 72-kDa gelatinase (matrix metalloproteinase-2) in the developing mouse craniofacial complex

Tissue remodelling is an important feature during embryogenesis. Although the matrix metalloproteinases are believed to participate in these processes, the relation between matrix metalloproteinases and tissue remodelling during craniofacial morphogenesis remains unclear. The purpose of the study was to look for the presence of enzymes involved in extracellular matrix degradation during craniofacial morphogenesis. Protein expression of the matrix metalloproteinase, 72-kDa gelatinase (matrix metalloproteinase-2, gelatinase A, 72-kDa type IV collagenase) was studied by gelatine zymography and by indirect immunofluorescence with conventional and confocal microscopy. In the anterior region of the developing mouse face, 72-kDa gelatinase was labelled mainly in the tips and peripheral regions of the nasal and facial prominences. Upon contact and fusion of the prominences, the staining was intensely localized to the zone of the fusion and the tips and peripheral regions of the nasal prominences and the maxilla. The labelling of 72-kDa gelatinase was also present in the peripheral regions of the mandible, second branchial arch, and the face around the developing eye. However, during lens vesicle formation, the staining of 72-kDa gelatinase was absent in the invaginated lens ectoderm. After the lens had completely detached from the surface ectoderm, the staining was resumed in the corneal epithelium and mesenchyme. Gelatine zymography was used to confirm the presence of active and latent 72-kDa gelatinase in the developing mouse craniofacial complex. Collectively, these data indicate that 72-kDa gelatinase may play a significant part in localized tissue remodelling during craniofacial morphogenesis and the aberrant expression or function of the enzyme could be involved in causing facial abnormalities.     

Radical abdominopelvic lymphadenectomy: historic perspective and current role in the surgical management of rectal cancer

Radical abdominopelvic lymphadenectomy for rectal cancer is based on the tenet that removal of all potentially involved lymphatic tissue will yield a lower rate of locoregional failure and improve survival. At centers with extensive experience with the procedure, the operating time is only modestly prolonged compared with conventional resection. Blood loss and postoperative hospitalization are not significantly increased. Urinary dysfunction and impotence associated with radical abdominopelvic lymphadenectomy (as high as 80 percent and 76 percent, respectively, in recent series) have been major deterrents to its more routine application. Preservation of the hypogastric plexus and even selective preservation of a unilateral S4 nerve root have been shown to reduce the occurrence of genitourinary complications. Improved five-year survival of 68 percent and local recurrence rates of 5 to 20 percent for TNM Stage III cancers have been achieved with radical abdominopelvic lymphadenectomy. These results compare favorably with recent trials of adjuvant chemoradiation after conventional resection in stage-matched patients. The rationale, evolution, and application of radical abdominopelvic lymphadenectomy to the surgical management of rectal cancer are critically examined. The potential benefits of radical abdominopelvic lymphadenectomy, which have been demonstrated in nonrandomized trials, should be evaluated in a prospective and properly randomized study to clearly establish or refute its efficacy.     

Evaluation and treatment of the infected foot in a community teaching hospital

More inpatient hospital days are used for the care of diabetic foot infection than for any other diabetic sequela. Both the number of lower extremity amputations and the overall treatment cost of treating diabetic infections may be reduced by using a team approach in the care of the infected diabetic pedal wound. The authors propose an evaluation and treatment protocol of infected pedal ulcerations in an urban, community teaching institution when admitted to an established, multidisciplinary diabetic foot care team. The hospital course of 111 patients admitted with a primary diagnosis of infected pedal ulceration are retrospectively reviewed. Results revealed an average-length hospital stay of 7.4 days with a 96% limb-salvage rate. The authors suggest that in the treatment of the infected pedal wound, a diabetic foot care team with a well developed treatment protocol may yield a consistently favorable outcome and a cost-effective hospital course.