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Biomedical subjects

G E Pierce

Publications and source records attributed to G E Pierce.

At least 55 records · Page 3Linked to original sources

Allogeneic versus semiallogeneic F1 bone marrow transplantation into sublethally irradiated MHC-disparate hosts. Effects on mixed lymphoid chimerism, skin graft tolerance, host survival, and alloreactivity.

In models of tolerance associated with mixed lymphoid chimerism, depletion of Thy 1+ cells from the allogeneic donor inoculum may decrease the level of chimerism achieved and the capacity of donor cells to induce tolerance. To determine whether the apparent role of Thy 1+ cells in the facilitation of bone marrow engraftment and induction of skin graft tolerance is related to alloaggression, the capacity of fully allogeneic C57BL/6J, H-2b BM cells to establish mixed lymphoid chimerism and skin graft tolerance in sublethally irradiated (2.5 Gy x 3) BALB/c, H-2d hosts was compared with that of semi-allogeneic BALB/c x C57BL/6J F1 H-2d/b BM cells which genetically lack the potential for graft-versus-host reactivity against parental recipients. The levels of mixed chimerism observed with allogeneic and semi-allogeneic F1 BM cells were nearly identical: 21.0 +/- 9.7% of spleen cells in H-2b BM-injected and 18.6 +/- 8.8% of spleen cells in H-2d/b BM-injected H-2d hosts were of donor allotype. There was no difference in the fraction of hosts rendered tolerant to C57BL/6J, H-2b skin grafts by H-2b vs. H-2d/b BM at either excess (94% vs. 92% tolerant) or threshold (37% vs. 40% tolerant) numbers of donor cells. Spleen cells from both types of mixed chimeras failed to respond to donor antigens in MLR. Both H-2b and H-2d/b BM-injected H-2d hosts rejected third party C3H/HeJ, H-2k skin grafts and responded to third party stimulators in MLR. Although these nonspecific allo-immune responses were not as strong as the responses of normal animals, they were suppressed to an equivalent degree in both types of chimeras. Graft-versus-host disease, if present in irradiated H-2b BM-injected hosts, did not significantly affect survival compared with survival of irradiated H-2d/b BM-injected animals. These results suggest that the tolerizing capacity of allogeneic BM does not depend upon GVHD and that allogeneic and semi-allogeneic BM establish mixed lymphoid chimerism and induce skin graft tolerance by similar mechanisms across a complete MHC disparity in sublethally irradiated adult hosts.

Animals↗

Pancreatogastrostomy: a safe drainage procedure after pancreatoduodenectomy.

The purpose of this study was to evaluate the role of pancreaticogastrostomy as an alternative method of restoring pancreaticointestinal continuity after pancreaticoduodenectomy. Since 1975, 45 patients have undergone pancreaticogastrostomy after pancreaticoduodenectomy at our institution. Pancreaticoduodenectomy was performed for pancreatic carcinoma (24 patients), ampullary carcinoma (8 patients), duodenal carcinoma (4 patients), common bile duct carcinoma (4 patients), pancreatic islet cell carcinoma (1 patient), trauma (1 patient), extensive colon carcinoma (1 patient), chronic pancreatitis (1 patient), and gastroduodenal artery aneurysm (1 patient). There was one operative death, for an overall operative mortality rate of 2%, and seven patients had major postoperative complications, for an overall morbidity rate of 15%. No pancreatic anastomotic leaks or other complications related to the pancreaticogastrostomy occurred. Twenty-four patients have died of recurrent carcinoma, with a mean survival of 25 months (range, 5 to 66 months), and 20 patients are alive and well, with a mean follow-up of 27 months (range, 2 to 106 months). Eight of these patients are alive 2 or more years after operation and four do not have exocrine pancreatic insufficiency. This experience confirms that pancreaticogastrostomy is a safe method of pancreatic drainage after pancreaticoduodenectomy and suggests that it may have technical advantages and therefore merits more widespread application.

Adult↗

Primary hypercoagulable states in general and vascular surgery.

Primary hypercoagulable states are increasingly recognized as causes of venous and arterial thromboembolism in surgical patients. Herein, we describe 10 patients with this syndrome who were diagnosed during a recent 1-year period. A family history and past medical history of thromboembolism and an unusual site of thrombosis are emphasized for accurate diagnosis. Although antithrombin III deficiencies were the most common abnormality found, we describe three patients with hypofibrinolytic syndromes and increased levels of tissue plasminogen activator inhibitor. The effectiveness of anticoagulation therapy in preventing recurrent thromboembolism is stressed.

Adolescent↗

The risk of stroke with occlusion of the internal carotid artery.

Reports of all cervicocephalic arteriograms (n = 1836) performed at one institution during a 10-year period were reviewed and the patients were classified into three groups according to the indication for arteriography. Group I included all patients with symptoms or findings compatible with occlusive disease of the carotid or vertebral artery (n = 806). Group II included patients with cerebrovascular symptoms unrelated to carotid or vertebral disease (e.g., patients with subarachnoid hemorrhage) (n = 367). Group III consisted of patients with no evidence of cerebrovascular disease (e.g., patients with primary and metastatic brain tumors) (n = 663). One hundred ten atherosclerotic occlusions of the internal carotid artery (ICA) were found in 106 patients in group I. Fifty-one percent of these patients had a history of stroke before arteriography, 24% had transient ischemic attacks (TIAs) or amaurosis fugax (AF), and 12% had nonhemispheric symptoms. Only 13% (1.7% of group I patients) were without symptoms. Ninety-one percent of the strokes and 75% of the TIAs or AF were ipsilateral to the ICA occlusion. Seventy-six percent of patients with stroke and 80% with ipsilateral TIAs or AF vs only 29% of patients without symptoms had contralateral stenosis of 60% diameter reduction or greater (p less than 0.003). No occlusions of the ICA occurred in groups II or III. Three hundred forty-six patients in groups II and III were more than 60 years of age. Assuming either Poisson or binomial distributions, the incidence of silent ICA occlusion in the population at large older than 60 years was estimated at less than 1% (p less than 0.03).

Adult↗

Hemodynamics of the hypogastric arterial circulation.

This study was designed to assess the major sources of collateral supply to the hypogastric arterial bed (HGA). Peak systolic HGA and radial arterial pressure were obtained before and after clamping a patent HGA and after additional clamping of the contralateral HGA, the contralateral external iliac artery (EIA), or the ipsilateral EIA both selectively and in combinations. These procedures were performed in 10 patients with aortoiliac (AI) aneurysms or occlusive disease. In seven patients with aneurysms, clamping the contralateral HGA decreased the HGA stump pressure index from 0.57 to 0.49 (p less than 0.05), and clamping only the ipsilateral EIA decreased the stump pressure index to 0.38 (p less than 0.001). In three patients with occlusive disease, clamping the contralateral HGA did not decrease the stump pressure index, clamping both the contralateral HGA and EIA decreased the index from 0.61 to 0.57 (p greater than 0.05), and clamping only the ipsilateral EIA decreased the pressure index to 0.40 (p less than 0.01). These data suggest that branches of the ipsilateral EIA femoral arterial system provide a more significant collateral pathway than the contralateral HGA. These results suggest that it is important to relieve occlusive disease in the ipsilateral EIA femoral arterial system if a patent HGA is ligated or bypassed during AI reconstructions. Conversely, it is especially important to preserve forward perfusion in a patent HGA in a patient with compromised ipsilateral EIA femoral runoff.

Aneurysm↗

Effects of Thy-1+ cell depletion on the capacity of donor lymphoid cells to induce tolerance across an entire MHC disparity in sublethally irradiated adult hosts.

Thy-1+ cell depletion with anti-Thy-1.2 mAb and complement markedly reduced the capacity of C57BL/6J, H-2b bone marrow to establish mixed lymphoid chimerism and induce tolerance to C57BL/6J skin grafts across an entire MHC disparity in BALB/c, H-2d hosts conditioned with sublethal, fractionated 7.5 Gy total-body irradiation. In this model tolerance can be transferred to secondary irradiated BALB/c hosts only by cells of C57BL/6J donor, not host, genotype isolated from the spleens of tolerant hosts. Thy-1+ cell depletion abolished the capacity of C57BL/6J donor cells from tolerant BALB/c host spleens to transfer tolerance. The capacity of semiallogeneic BALB/c x C57BL/6J F1, H-2d/b donor BM and spleen cells to induce chimerism and tolerance to C57BL/6J skin grafts in BALB/c parental hosts was also reduced by Thy-1+ cell depletion. Thus the requirement for donor Thy-1+ cells cannot be explained simply on the basis of alloaggression. It is unlikely that the requisite Thy-1+ cells are nonspecific suppressor cells: Thy-1+ cell depletion had no effect on the slight but significant prolongation of third-party C3H/HeJ, H-2k skin grafts in irradiated BALB/c hosts injected with allogeneic C57BL/6J or semiallogeneic BALB/c x C57BL/6J F1 BM compared to irradiated controls injected with medium only. Furthermore, injections of semiallogeneic F1 spleen cells had no significant effect on the survival of the third-party grafts, although these cells were fully capable of inducing tolerance, and their capacity to induce tolerance was significantly reduced by Thy-1+ cell depletion. The requirement for a specific population of lymphoid cells, i.e. Thy-1+, remains unexplained but suggests that donor cells might play a role in the induction or maintenance of tolerance in this model other than merely providing a circulating source of donor antigens.

Animals↗

Multicenter trial of cadexomer iodine to treat venous stasis ulcer.

In a crossover study designed to judge the efficacy of the topical polymeric starch iodophore, cadexomer iodine, in accelerating the healing of venous stasis ulcers, 75 patients were prospectively randomly assigned to receive either cadexomer iodine or standard treatment. The control treatment consisted of a standard saline wet-to-dry compressive dressing. The patients improved with either treatment: ulcers healed more than twice as rapidly using cadexomer iodine (n = 38) as with standard therapy (n = 37) (P = .0025). Ulcers treated with cadexomer iodine showed trends toward less pain, exudate, pus, and debris, and a more rapid development of granulation tissue. Twelve patients crossed over from control treatment to the use of cadexomer iodine because of a failure to heal, but no patients switched to control therapy from the use of cadexomer iodine (P = .01). Except for occasional mild local burning in wounds treated with cadexomer iodine, no adverse effects were noted with either regimen.

Adult↗

A comparison of diabetics and nondiabetics with threatened limb loss.

One hundred seventeen patients with threatened limb loss were evaluated. Seventy-three of these patients underwent vascular reconstruction. Diabetics had a significantly higher incidence of ischemic ulceration and gangrene when compared with nondiabetics. Nondiabetics typically presented with rest pain. The outcome of foot salvage surgery was evaluated by postoperative ankle-branchial indices as well as limb salvage rates. Ankle-brachial indices increased significantly in both groups. Fifty-five percent of the diabetics and 67 percent of the nondiabetics had a postoperative ankle-brachial index of 0.8 or greater. Overall foot salvage at 1 year was 84 percent. Foot salvage in patients with diabetes was 78 percent compared with 86 percent in nondiabetics. In this subset of patients with threatened limb loss confirmed by hemodynamic measurements, the results of vascular reconstruction were comparable in both diabetic and nondiabetic patients.

Adult↗

Vascular graft selection.

Twenty to thirty per cent of patients with arterial injuries and some patients with venous injuries require interpositional grafting. The first choice of grafting material for both arterial and venous injuries is autogenous vein. Injuries to large vessels such as the aorta and superior vena cava may necessitate synthetic prostheses. Synthetic aortic prostheses have excellent long-term patency rates, but the same materials are much less likely to remain patent in the vena cava. Panel or spiral grafts constructed from saphenous vein appear to be the best replacement for this vessel. Autogenous veins are present in different diameters ranging from a mean of 6.4 mm in the saphenous vein to a mean of 1.8 cm in the internal jugular vein. The thickest autogenous vein is the saphenous vein, and thus it is preferred for medium-sized and small arteries. The authors prefer the larger 7.5-mm cephalic vein for replacement of medium-sized veins. In the absence of suitable saphenous vein, the cephalic vein is also the choice for arterial interposition grafts. Although there are few reports of the use of arterial autografts in vascular trauma, the surgeon should be aware that autografts may be ideal for vascular injuries in children and for isolated injuries with severe contamination. Finally, the use of synthetic grafts in injuries where adequate tissue coverage is not possible may result in immediate limb salvage, but the incidence of limb loss in this situation will be extremely high.

Arm Injuries↗

Successful transplantation of blood group A2 kidneys into non-A recipients.

The ABO subgroup A2 has been reported to be less reactive with the anti-A1 antibody naturally occurring in the serum of group O and B recipients and to occur in approximately 20% of group A individuals. Between March 1986 and February 1987, the Midwest Organ Bank (MOB) in Kansas City, screened all group A renal donors for the A2 subgroup. A total of 190 cadaverdonor kidneys were retrieved during this time, of which 68 were subgroup A1 and 16 were subgroup A2 (incidence of A2 = 19% of As and 8.5% of all donors). Of the subgroup A2 kidneys, 13 were transplanted into 9 group O and 4 group B recipients. One group O recipient received an HLA-identical A2 living-related graft. Recipients were not preselected or modified by splenectomy, plasmapheresis, or other means, and were treated with cyclosporine, steroids--and, in most cases, azathioprine, after transplantation. There was one hyperacute rejection and there were 5 acute cellular rejection episodes, 3 of which were reversed. One additional patient died at 2.5 months with a functioning graft. Including the successful living-related graft, 10 of 14 patients (71%) have functioning grafts, with a follow-up of 5 to 14 months, and a mean creatinine of 1.7 mg/dl. We find that the A2 subgroup represents a small but important minority of A donors, and that transplantation into non-A recipients can generally, but not universally, be safely accomplished. We recommend the screening of A donors for the A2 subgroup in both the cadaver-donor and living-related groups, and suggest that the utilization of A2 donors in non-A patients may contribute to the transplantation of group O and highly sensitized patients--and, in some cases, improve the degree of HLA matching.

ABO Blood-Group System↗

The critical hypogastric circulation.

Eleven patients had ischemic complications secondary to ligation, hypoperfusion, exclusion, or thrombosis of the hypogastric arteries after aortoiliac reconstruction or spontaneous aortoiliac thrombosis. Ligation of one hypogastric artery resulted in persistent ipsilateral buttock claudication in three patients. Bilateral acute hypogastric artery ischemia occurred in eight patients and resulted in paralysis in all eight patients, buttock necrosis in four patients, anal and bladder sphincteric dysfunction in two patients, and colorectal ischemia in three patients. Five of these patients (63 percent) died. The mortality rate was 100 percent when buttock necrosis developed. In most of these patients, the neurologic deficit suggested ischemic injury of the lumbosacral plexus rather than spinal cord ischemia. These complications occurred despite patent bypass grafts to the iliac or femoral vessels. These observations suggest that it is essential to maintain patency of the hypogastric vessels in all aortoiliac reconstructions.

Aged↗

Diagnostic value of open lung biopsy in immunocompromised patients.

The records of 46 immunocompromised patients who presented with diffuse pulmonary infiltrates were reviewed to determine the role of open lung biopsy in their management. Fifty-two percent of these patients had underlying hematologic malignancies and 54 percent had received chemotherapy within 3 months prior to biopsy. Forty-six percent were receiving immunosuppressive doses of corticosteroids. A specific diagnosis was obtained in 30 of the 46 patients (65 percent). Fifteen of these patients had pulmonary infections. Nonspecific diagnoses were obtained in 16 of the 46 patients (45 percent). Therapy was altered in a total of 27 patients and 17 of these patients responded to treatment. Overall survival at 1 year was 41 percent. Forty-eight percent of the patients in whom therapy was changed survived 1 year, and 31 percent of the patients in whom therapy was not changed survived 1 year. No deaths were attributable to the operative procedure. The complication rate was acceptable. Open lung biopsy is an important technique in evaluating and determining therapy in immunocompromised patients who present with diffuse pulmonary infiltrates.

Adolescent↗

Comparative studies of computerized tomography and mediastinoscopy for the staging of bronchogenic carcinoma.

The accuracy of mediastinal computerized tomographic scans for the staging of bronchogenic carcinoma varies between institutions. In the present study, the sensitivity rate was 57 percent, the specificity rate 69 percent, and the overall accuracy rate 64 percent, all of which were generally lower than rates reported in the recent literature. Different scanning equipment, diagnostic criteria, and patient populations may all contribute to this variance. The data in this report suggest that tumor histologic type and location also influenced the accuracy of computerized tomography. On the basis of this study and review of the literature, it is recommended that any given institution assess the accuracy of its own computerized tomographic mediastinal scans before substituting scanning for mediastinoscopy in the preoperative staging of bronchogenic carcinoma.

Adult↗

Post-thyroidectomy hypocalcemia. Incidence and risk factors.

Two hundred twenty-one patients undergoing thyroidectomy were analyzed for factors increasing the risk of postoperative hypocalcemia. Eighty-three percent of all patients experienced hypocalcemia postoperatively, with 13 percent requiring some treatment for symptoms. Patients with advanced thyroid cancer, Graves' disease, or other manifestations of preoperative hyperthyroidism had significantly increased rates of hypocalcemia compared with patients with small cancers or benign euthyroid disease. Total thyroidectomy, repeat thyroidectomy, and thyroidectomy plus neck dissection all significantly increased the incidence of permanent hypocalcemia, whereas lobectomy or subtotal thyroidectomy for benign euthyroid disease were low risk operations. Inadvertent excision of more than one parathyroid gland during thyroidectomy also significantly increased the rate of permanent hypocalcemia.

Adolescent↗

Spontaneous dermatophytosis due to Microsporum canis in rabbits.

Reports of naturally occurring Microsporum canis infection in the rabbit are rare. During the tenth week of a 91 day percutaneous toxicity study, 17 of 30 adult New Zealand white rabbits developed skin lesions varying from multiple papules to ringed lesions 1 X 2 cm in diameter. The lesions were not pruritic. Hair and scale samples taken from rabbits with lesions were cultured for dermatophytes. Based upon colony morphology and macroconidial characteristics, M canis identification was confirmed. At the time of necropsy, fluorescence was observed in three animals examined with a Wood's lamp, and of 10 rabbits that were positive on culture, seven were clinically normal. Microscopically, hair follicles contained spores and mycelia. The source of this outbreak was not determined. Tap water was cultured and found negative for pathogenic fungi. These findings document M canis infections in laboratory-housed New Zealand white rabbit, such an asymptomatic carrier state should be considered in this outbreak. The significance of dermatomycosis in laboratory animals is primarily as a zoonosis and a research complication.

Animals↗