Biomedical subjects

J S Gould

Publications and source records attributed to J S Gould.

11 recordsLinked to original sources

PubMed1992

The de-endothelialized rat carotid arterial graft: a versatile experimental model for the investigation of arterial thrombosis.

A novel model of arterial thrombosis was developed. A mechanical endothelium-denuding injury was created (using a scalpel blade) on harvested, freezer-stored rat carotid arteries. Vessel length of 5 mm. were grafted into the femoral arteries of recipient Sprague-Dawley rats using microvascular anastomotic technique. Patency rates in untreated animals were compared with those in animals receiving systemic aspirin or heparin. The control group patency after 2 hours of flow was 15%, while grafts in aspirin- and heparin-treated animals achieved 35% and 95% patency rates, respectively. Uninjured non-frozen carotid grafts in untreated animals yielded a 95% patency rate, while frozen grafts achieved an 80% patency. Therapeutic levels of aspirin, heparin, and urokinase were confirmed through tail bleeding and whole blood clotting tests, as well as platelet aggregation studies and scanning electron microscopy of the graft lumenal surfaces. A long-term series using syngeneic grafts placed in recipients (Lewis-to-Lewis) and employing systemic heparinization demonstrated maintenance of patency for 4 weeks. Scanning electron microscopy revealed good re-endothelialization, well advanced by one week. Histology confirmed the regrowth of endothelial cells, but showed sparse cellular repopulation of medial and adventitial layers. The mechanical injury model was compared to enzymatic de-endothelialization (using trypsin or collagenase), for which patency rates were similar (10% and 0%, respectively). Trypsin de-endothelialized vessels were tested in vitro for the amount of active trypsin remaining bound to the lumenal surface; no detectable activity was found when trypsin inhibitor was applied following trypsin treatment. The versatility of allowing both in vitro evaluation and in vivo patency assessment demonstrates the uniqueness and value of this new model, offering an avenue toward more direct investigations of surface-mediated thrombotic processes.

Anastomosis, Surgical↗

PubMed1992

Maintenance of patency after vascular trauma by topical irrigation with a peptide homologous to the carboxy-terminus of the fibrinogen gamma chain.

Synthetic peptides with amino acid sequences homologous to the carboxy-terminal sequence of the gamma chain of human fibrinogen were evaluated for their capacity to inhibit thrombus development. A 21-residue peptide effectively inhibited surface-mediated fibrin clot propagation in vitro. Since this effect was localized to the surface, we proceeded with in vivo evaluation, using site-specific topical application only. In a rat model of arterial trauma and microvascular repair, topical application of the 21-residue peptide significantly reduced the rate of thrombosis to 17%, as compared with a control rate of 83%; in comparison, a 12-residue homologue reduced the thrombosis rate only modestly to 61%, which was not significant compared with the control rate. These results indicate the feasibility of antithrombotic therapy with topically applied agents, an approach that may obviate the use of systemic anticoagulation in extremity-replantation surgery.

Administration, Topical↗

PubMed1992

Microvascular salvage procedures with adjuvant antithrombotic therapy for restitution of patency in a rat model.

Thrombosis following microvascular anastomosis requires further surgical intervention, involving anastomotic resection and reanastomosis or interpositional vein grafting. This study was undertaken to investigate different methods of salvaging thrombosed vessels, using a rat-vein model of error-induced thrombosis. Vessels were reconstructed 4 hr after the onset of thrombosis, using one of three methods: Group 1--removal of the erroneously placed stitch; Group 2--anastomotic resection and re-anastomosis; and Group 3--resection and replacement with a vein graft. Adjuvant antithrombotic therapy was simultaneously evaluated, assessing the influence of systemic Iloprost or heparin. Patency rates at one day postoperatively were 0 percent, 12.5 percent and 37.5 percent for Groups 1, 2, and 3, respectively. Following Iloprost infusion, these rates increased to 25 percent, 25 percent, and 56.3 percent, respectively and, following heparin administration, to 50 percent, 68.8 percent, and 81.8 percent, respectively. Significant increases were found for vein grafting (Group 3), and for the heparin-treated subgroups using all three methods. Effective levels of both Iloprost and heparin were confirmed by increases noted in rat-tail bleeding times. Significant rates of recanalization by three days following one-day occlusion were found in Groups 1 and 2. These results support the application of vein-graft replacement for thrombosed veins, concurrently with systemic heparinization. This study further confirms the high rate of recanalization seen in thrombosed rat femoral veins.

Anastomosis, Surgical↗

PubMed1992

A simultaneous distal phalanx avulsion fracture with profundus tendon avulsion. A case report and review of the literature.

Avulsion injuries of the flexor digitorum profundus are fairly common injuries, yet simultaneous avulsion fractures of the insertion of this tendon associated with rupture of the tendon from the bony fragment is rarely described and is more complicated. In the 24-year-old athlete, the injury was classified according to the system of Leddy and Packer. The authors' method of treatment is also described. Similar cases presented in the literature are reported, with emphasis on pathomechanism, physical findings, and surgical repair method. In this rare injury, stabilization of the distal interphalangeal joint is necessary even at the expense of early motion.

Adult↗

PubMed1992

Management of acute and chronic vascular injuries to the arm and forearm. Indications and technique.

Acute arterial injuries of the upper extremity account for half of civilian arterial injuries in the United States. The great majority of these injuries are due to penetrating trauma, with stab wounds and gunshot wounds being the most common cause. The history of the injury and a careful physical examination will identify most injuries. Arteriography should be performed when a vascular injury is suspected but not confirmed by physical examination. Reconstruction of critical vascular lesions is essential for restoration of flow distally. Noncritical lesions may be repaired in most cases, with long-term patency rates averaging 50% to 68%. Although amputation is uncommon after upper-extremity vascular injury, long-term disability can be significant in those patients with concomitant nerve injury. Chronic upper-extremity ischemia may be secondary to atherosclerotic occlusive disease, aneurysms, or arteriovenous fistulas. Angiography will delineate the diseased or occluded arterial segment, allowing bypass to be successful in more than 90% of cases. With careful attention to proper diagnosis and treatment, good to excellent long-term relief of symptoms can be obtained.

Acute Disease↗

PubMed1979

Chronic tenosynovial hand infection from Mycobacterium terrae.

A 23-year-old healthy man suffered a puncture wound from the fin of a catfish. Chronic tenosynovitis subsequently developed. Synovectomy was performed and cultures yielded Mycobacterium terrae. This organism, usually considered nonpathogenic, has only rarely been associated with human disease. This case further supports the role of this organism as a potential human pathogen and further suggests that M terrae should be considered in aquatic-associated hand tenosynovitis.

Adult↗

PubMed1979

Interpositional microvascular vein grafting.

The application of interpositional microvascular vein grafting in replantation surgery, a detailed account of the technique developed and utilised in the microvascular research and training laboratory, and clinical experience with this technique are described. Vein grafting is of particular value to eliminate tension in anastomoses, bridge vascular defects, and has made feasible the salvage of severe crushing and avulsion amputation in the hand.

Amputation, Traumatic↗

PubMed1979

A mechanised microirrigation system.

A mechanised microirrigation system for microvascular surgery, which is operated by a foot pedal, utilises a large sterile reservoir, and allows control of flow rate and volume, has been designed for use in the laboratory and operating room.

Humans↗

PubMed1979

Capsulectomy of the metacarpophalangeal and proximal interphalangeal joints.

From July 1975, through March, 1978, 105 metacarpophalangeal joint capsulectomies in 37 patients, 47 dorsal proximal interphalangeal (PIP) capsulectomies in 26 patients, and 65 volar PIP capsulectomies in 41 patients were performed. The procedures were done after conservative methods had failed, and the results were tabulated in each area by diagnostic category. In the major group in which stiffness resulted from fracture and crushing injuries, average gains of 13 degrees to 18 degrees of active motion were achieved, with a change in arc of motion, while nerve paralysis patients did substantially better. The study should clarify expectations from the procedure; functional gains may still be significant.

Adolescent↗

PubMed1978

Carpal tunnel syndrome in pregnancy.

Occurrence of the carpal tunnel syndrome in pregnancy was studied by examining 100 consecutive obstetric admissions. Twenty-one patients reported paresthesias or hypesthesia in the median nerve sensory distribution of the hand during the pregnancy; eight of these had decreased sensation subjectively at the time of examination one to three days after delivery; two had trophic changes, loss of sudomotor function, thenar atrophy, and decreased two-point discrimination; and one had a delay in motor conduction time across the carpal tunnel. Of the 21 patients, 18 became asymptomatic before or shortly after delivery. The remaining three were asymptomatic three months after delivery. We conclude that the incidence of symptoms is probably greater than usually appreciated, but that few patients require treatment. Steroid injection may occassionally be necessary, but the need for surgical intervention is rare.

Carpal Tunnel Syndrome↗

PubMed1977

Metacarpophalangeal joint arthroplasty with silicone-Dacron prostheses (Niebauer type): six and a half years' experience.

Four hundred and forty-one silicone-Dacron arthroplasties done since 1968 were reviewed. Results were influenced by both durability and immediate fixation of the prosthesis, disease characteristics, speed of progression, the amount of hand stress, the extent of soft tissue release, and postoperative dynamic and protective splinting. Dislocations were eliminated by a woven tie-in holding the prosthesis to bone; prosthetic buckling was eliminated by soft tissue release, sufficient bone removal, and suture of the dorsal capsule to the extensor mechanism. Early prosthetic models fractured easier than did current ones. Seventeen percent of the combined 4, 5, and 6 year follow-up prostheses fractured, and 30% of the 6 year prostheses have fractured. Function was not affected, however, and protheses have not been replaced. We continue to use silicone-Dacron protheses with immediate tie-in to bone.

Arthroplasty↗