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Biomedical subjects

J A Light

Publications and source records attributed to J A Light.

108 records · Page 6Linked to original sources
PubMed1977

Successful renal vein reconstruction with bovine arterial heterografts.

Extensive damage to a short right renal vein complicated transplant surgery in two patients. The use of a segment of modified bovine arterial heterograft permitted successful transplantation in both cases. These results are in contrast to the reported inability of bovine arterial heterografts to remain patent elsewhere in the systemic venous system.

Adult↗
PubMed1976

Procoagulant and platelet aggregating properties of antilymphocyte sera.

Ten anti-human lymphocyte sera in clinical use at six transplant centers and five anti-nonhuman lymphocyte sera were studied for their procoagulant and platelet-aggregating properties. This investigation was initiated following the observation of a clinical episode of renal artery thrombosis, associated with the use of one of the sera in a patient who had received a cadaveric renal transplant. The procoagulant from this serum shortened the clotting times of individual samples deficient, respectively, in factors XII, XI IX, X VIII, and VII. Esterolytic activity, demonstrated on the substrate benzoylarginine ethyl ester, was completely inhibited by phenylmethylsulfonyl fluoride, but coagulant activity was variably affected. The platelet-aggregating activity (PAA) has been identified as a complement-fixing gamma G antibody that was absorbed from the antilymphocyte serum (ALS) with human spleen lymphocytes. Five of the ten anti-human lymphocyte sera showed varying procoagulant activity (PCA), and six sera demonstrated PAA. Three sera contained both activities. The presence of both PCA and PAA in the same preparation may predispose patients to thrombotic events, particularly if administered intravenously. Sera should be screened for PCA and PAA prior to clinical use, and sera with these properties should be used with caution.

Animals↗
PubMed1976

Lymphocyte blastogenesis in patients receiving hemodialysis.

Lymphocyte blastogenic transformation in response to plant lectins and allogenic cells was studied in patients with nonuremic, far-advanced, chronic renal failure and in healthy controls. Cell cultures were studied in the presence of normal sera, patient's sera, and with media of different buffering capacities. Minimal blastogenic depression was observed when patient's lymphocytes were cultured in indifferent plasma with effective bicarbonate buffering compared with the use of pooled patient's plasma or HEPES buffer. Fresh plasma in culture depressed concanavalin A (Con A) blastogenesis. The data suggest that, under optimal conditions, lymphocytes from patients with chronic severe renal insufficiency are more responsive to stimuli than previously reported and as a group are near normal control values. Further, the defect observed may be a result of intracellular acidosis.

Adult↗
PubMed1976

Perfusion-related injury in renal transplantation.

The implantation and one hour post-transplant renal biopsies from three types of allograft recipients were compared with a blind grading system: (1) 25 cadaver kidneys preserved by pulsatile perfusion, (2) seven cadaver kidneys preserved by simple hypothermia following electrolyte solution flush, (3) 18 kidneys from living-related donors. Significant lesions were found only in cadaver kidneys which had received pulsatile preservation. Microscopic findings were correlated with perfusing agent, length of perfusion and its characteristics, and subsequent clinical course of the patient. Perfusion-related injury was found to be morphologically identical to hyperacute rejection, although the lesion is produced by quite different mechanisms. Pulsatile preservation appears to be associated with a spectrum of mechanical endothelial injury ranging from minute breaks visible only ultrastructurally to areas of complete denudation baring the basement membrane. The exposed collagen activates the clotting sequence resulting in platelet and fibrin deposition, whereas in classical hyperacute rejection the triggering mechanism is cytotoxic recipient antibody. The extent of perfusion-related injury correlates well with length of preservation, quantity of fibrin deposited, and, most importantly, with both the immediate and long-term post-transplant failure rate. In some patients the injury appears to be produced by cytotoxic antibodies in the plasma perfusate, which combine with antigens in the kidney ex vivo. The Ag-Ab complex activates complement and coagulation sequences in vivo after reimplantation. Early results with albumin or purified plasma fraction perfusates suggest this portion of perfusion-related injury can be eliminated. Comparison of pre- and postimplantation biopsies of the kidneys preserved by simple hypothermia or by pulsatile preservation suggests that perfusion-related injury is much more common than is true hyperacute rejection mediated by recipient cytotoxic antibodies. We suggest that the term "hyperacute rejection" be reserved for situations where significant endothelial drainage has been excluded by preimplantation biopsy and where recipient cytotoxic antibodies can be proved.

Cadaver↗
PubMed1975

Adverse effects of meglumine diatrizoate on renal function in the early post-transplant period.

Thirty-four renal transplant recipients received drip infusion urograms from 2-24 days post-transplantation. Twenty-two patients exhibited changes in renal function within 1-4 days of the urogram that were indistinguishable from allograft rejection: a tender, swollen kidney, elevation of serum creatinine, oliguria, decreased urine sodium concentration, weight gain, and hypertension. Two patients developed acute tubular necrosis and required hemodialysis, but renal function in the remaining 20 patients improved after therapy for "graft rejection" with i.v. methyprednisolone sodium succinnate. Kidneys from older-age donors that were functioning suboptimally and kidneys which exhibited subsequent clinical allograft rejection were more at risk for contrast media toxicity. This suggests that occult vascular lesions may have been present in the allograft which were exacerbated when exposed to the irritant vascular effects of contrast media, producing a mild, reversible toxic nephritis. However, several kidneys with normal function and several kidneys which never exhibited rejection activity were also adversely affected by exposure to contrast media. It appears these agents should be used cautiously, if at all, in the early post-transplant period.

Creatinine↗
PubMed1975

Immune injury from organ preservation. A potential cause of hyperacute rejection in human cadaver kidney transplantation.

Two pairs of plasma-perfused human cadaver kidneys were rejected in a hyperacute manner by recipients who had not previously received a transplant. Crossmatches between recipient sera and donor lymphocytes were negative in all cases. A fifth kidney was plasma-perfused but not transplanted because the perfusate was shown to be cytotoxic to donor lymphocytes. IgM and complement, but not IgG, were demonstrated in these kidneys by immunofluorescent microscopy and confirmed by further immunological studies. The IgM was broadly reactive against multiple HL-A specificities and was present in 11 percent of sera from normal, healthy male donors. It appears from our studies that cytotoxic IgM may be present in homologous plasma and cause immune injury to the kidney during ex vivo pulsatile preservation. This may be responsible for some cases of otherwise unexplained accelerated allograft rejection.

Blood Donors↗
PubMedDate not supplied

Phase I results of pullback atherectomy for hemodialysis access.

PURPOSE: Balloon angioplasty and directional atherectomy frequently have short-lived results for stenoses associated with hemodialysis. Results are reported for a phase I trial of the pullback atherectomy catheter (PAC) for treatment of hemodialysis access-related stenoses. PATIENTS AND METHODS: Six intragraft and six venous stenoses in nine patients were treated with the PAC. Two lesions were treated with adjunctive balloon angioplasty, and two were treated with adjunctive directional atherectomy. Clinical and angiographic follow-up were obtained for all patients. All specimens were examined histologically. RESULTS: Initial procedural success was achieved in 83% of stenoses (10 of 12). For intragraft stenoses, the 6-month primary patency was 60% (three of five) and the 6-month secondary patency was 80% (four of five). All six venous stenoses restenosed or thrombosed within 3 months. All specimens contained fibrous plaque or intimal hyperplasia. In addition, all six venous stenosis specimens contained media and two contained adventitia. Significant complications during treatment of venous stenoses included severe venous spasm in three and venous pseudoaneurysms in two. One PAC tip fracture occurred during treatment of an intragraft stenosis. CONCLUSION: Pullback atherectomy is potentially safe and effective for intragraft stenoses; however, it is not safe or effective for venous stenoses.

Adult↗