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Biomedical subjects

W S Moore

Publications and source records attributed to W S Moore.

At least 91 records · Page 5Linked to original sources
PubMed1994

Carotid endarterectomy without arteriography.

Arteriography has been considered the "gold standard" for evaluation of the cerebrovascular circulation prior to carotid endarterectomy. However, arteriography is associated with a neurologic complication rate of up to 12% in certain high-risk groups. Previous studies have shown that the duplex scanner has greater sensitivity than arteriography when both are correlated to the surgical specimen. From January 1986 to December 1991 a total of 174 carotid endarterectomies were performed in 152 patients, of which 61% were symptomatic. A total of 110 carotid endarterectomies in 92 patients were performed without the use of arteriography. Of the 64 patients in whom arteriograms were obtained, 33 were made at consultation and the others for various indications. Operative findings confirmed the duplex scan findings in all cases. A total of 91% of patients had intraoperative completion arteriograms. Of the 55 patients who also had intracranial views taken, two had a 50% siphon stenosis and one patient had a small intracranial aneurysm. None of these findings would have changed our management. The overall neurologic complication rate was one (0.66%) death due to stroke and four (2.6%) patients with transient ischemic attacks. Carotid endarterectomy can be safely performed without preoperative arteriography based on a detailed history and physical examination that includes bilateral upper extremity blood pressures and a duplex scan performed by a validated laboratory.

Angiography↗
PubMed1994

Suppression of intimal hyperplasia in a rabbit model of arterial balloon injury by enalaprilat but not dimethyl sulfoxide.

Intimal hyperplasia appears to result from the deposition of collagen and matrix by medial myofibroblasts, which are stimulated in response to vascular injury. We hypothesized that pharmacologic inhibitors of fibroblast proliferation would suppress the development of intimal hyperplasia. We evaluated the effect of two agents known to inhibit fibroblast proliferation in vitro: enalaprilat, an angiotensin-converting enzyme (ACE) inhibitor, and dimethyl sulfoxide (DMSO), an organic solvent. Thirty-five New Zealand white rabbits underwent standardized balloon catheter injury of the left common carotid artery. Experimental groups received daily intramuscular injections of the following: group I (n = 15), saline solution; group II (n = 10), 0.07 mg/kg enalaprilat; and group III (n = 10), 2 ml/kg of a 25% by weight DMSO solution. Injections were started 1 day prior to injury and continued 5 days a week for 8 weeks. Carotid arteries were perfusion-fixed at 12 weeks and cross-sectioned for measurement by planimetry. Intimal hyperplasia was measured as the ratio of the absolute area of intimal hyperplasia to the normalized area enclosed by the internal elastic lamina (IH/IEL) and was expressed as a percent. Mean values for IH/IEL were as follows: group I (control), 20.6 +/- 2.3%; group II (enalaprilat), 9.5 +/- 0.7%; and group III (DMSO), 17.6 +/- 2.6%. Enalaprilat-treated animals demonstrated a statistically significant suppression of intimal hyperplasia compared with controls (p < 0.01, ANOVA, Student's t test), whereas the DMSO-treated group did not. We conclude that enalaprilat is effective in suppressing the development of intimal hyperplasia in this model of arterial injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1994

Continuous postoperative intra-arterial urokinase infusion in the treatment of no reflow following revascularization of the acutely ischemic limb.

The loss of distal tissue perfusion sufficient for limb salvage following restoration of inflow to an acutely ischemic extremity has been referred to as the "no-reflow" phenomenon. We hypothesized that patients with no reflow and limb-threat ischemia might benefit from prolonged postoperative intra-arterial infusion of the thrombolytic agent urokinase (UK). Twelve patients with arteriographic and clinical evidence of no reflow following a lower extremity arterial thrombectomy and/or bypass procedure were treated with a continuous intra-arterial UK infusion in the immediate postoperative period. The mean duration of UK infusion was 47 hours (range 15 to 112 hours). The mean rate of infusion was 58,000 units/hr (range 30,000 to 100,000 units/hr). Seven patients required transfusion for bleeding from the treated extremity (mean 3.4 units packed cells) and one required reoperation for a groin hematoma. Plasma fibrinogen levels remained within the normal range in all patients, and no systemic bleeding complications were encountered. The intra-arterial UK infusion resulted in limb salvage in 7 of 12 patients. Six patients have viable, functional extremities at a mean follow-up interval of 24.9 months (range 6.4 to 49.7 months). One patient required below-knee amputation 6 months after treatment for progressive ischemia. The other five patients required below-knee amputation during the same hospitalization after UK failed to restore distal perfusion. The postoperative period is widely considered to be a contraindication to thrombolytic therapy. Our experience indicates that while UK may cause bleeding from the treated extremity, which in some cases requires transfusion, there is no evidence of systemic fibrinolysis or systemic hemorrhage.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1994

Thoracoscopic cervicodorsal sympathectomy: preliminary results.

PURPOSE: The purpose of this study was to determine the feasibility, safety, and efficacy of thoracoscopic cervicodorsal sympathectomy. METHODS: From March 1990 to December 1993, we performed 21 thoracoscopic sympathectomies in 19 patients. There were 13 women and six men; age 17 to 64 years, mean 37 years. Thirteen procedures were performed on the left side and eight on the right. Indications for surgery were causalgia/reflex sympathetic dystrophy in nine patients, Raynaud's/vasculitis in six, hyperhidrosis in five, and medically refractory cardiac arrhythmia in one. RESULTS: The T1-4 sympathetic ganglia were readily identified, dissected free, and resected thoracoscopically in 19 cases, and the T3-7 ganglia were resected with thoracoscopy in one case. One case required conversion to an open thoracotomy because of dense scar from a previous first rib resection, which obscured the anatomy. Histologic confirmation of ganglia were obtained in all 21 cases. Operative duration ranged from 1.0 to 3.5 hours. Estimated blood loss was 5 to 300 cc, mean 42 cc, median 10 cc. No patient required transfusion. All 21 patients had an excellent immediate sympathectomy response. Transient Horner's syndrome developed in two patients. Postoperative residual pneumothorax (< 10%) occurred in three cases and resolved spontaneously without further treatment. In one patient pleural effusion and pneumothorax developed, which were treated with the reinsertion of the chest tube. Postoperative pain was well controlled with oral analgesics. Hospital stay was 1 to 4 days, mean 2 days, median 1 day. Follow-up at 1 to 42 months, mean 11 months, median 6 months, showed continued evidence of sympathectomy effect in all patients, except one who died of her underlying disease 1 month after operation. CONCLUSIONS: We conclude that thoracoscopic sympathectomy is feasible, safe, and effective. Further studies are indicated to confirm its long-term benefits and to determine optimal thoracoscopic techniques.

Adolescent↗
PubMed1994

Repair of abdominal aortic aneurysm by transfemoral endovascular graft placement.

PURPOSE: The authors describe the initial clinical experience with a new device, approved by the FDA for investigation, for repair of abdominal aortic aneurysm by transfemoral endovascular insertion of an aortic graft. METHODS: Sixty-nine patients with abdominal aortic aneurysms were screened, and ten were found to be suitable for endovascular grafting. Repair was done in the operating room using general anesthesia. One femoral artery was surgically exposed, and the device, containing a premeasured graft with proximal and distal self-expanding fixation devices, was inserted with fluoroscopic control through an open arteriotomy. FINDINGS: Eight of ten patients underwent successful graft placement, and two patients required conversion to an open repair. On follow-up, six of eight patients who underwent graft placement functioned normally, with documented aneurysm thrombosis. Two patients who underwent graft placement functioned normally, with contrast computed tomography evidence of incomplete aneurysm thrombosis, but without further expansion. CONCLUSION: Transfemoral repair is safe and appears to be effective. Phase II study currently is appropriate, with need for long-term follow-up.

Aged↗
PubMed1993

Efficacy of carotid endarterectomy for asymptomatic carotid stenosis. The Veterans Affairs Cooperative Study Group.

BACKGROUND: The efficacy of carotid endarterectomy in patients with asymptomatic carotid stenosis has not been confirmed in randomized clinical trials, despite the widespread use of operative intervention in such patients. METHODS: We conducted a multicenter clinical trial at 11 Veterans Affairs medical centers to determine the effect of carotid endarterectomy on the combined incidence of transient ischemic attack, transient monocular blindness, and stroke. We studied 444 men with asymptomatic carotid stenosis shown arteriographically to reduce the diameter of the arterial lumen by 50 percent or more. The patients were randomly assigned to optimal medical treatment including antiplatelet medication (aspirin) plus carotid endarterectomy (the surgical group; 211 patients) or optimal medical treatment alone (the medical group; 233 patients). All the patients at each center were followed independently by a vascular surgeon and a neurologist for a mean of 47.9 months. RESULTS: The combined incidence of ipsilateral neurologic events was 8.0 percent in the surgical group and 20.6 percent in the medical group (P < 0.001), giving a relative risk (for the surgical group vs. the medical group) of 0.38 (95 percent confidence interval, 0.22 to 0.67). The incidence of ipsilateral stroke alone was 4.7 percent in the surgical group and 9.4 percent in the medical group. An analysis of stroke and death combined within the first 30 postoperative days showed no significant differences. Nor were there significant differences between groups in an analysis of all strokes and deaths (surgical, 41.2 percent; medical, 44.2 percent; relative risk, 0.92; 95 percent confidence interval, 0.69 to 1.22). Overall mortality, including postoperative deaths, was primarily due to coronary atherosclerosis. CONCLUSIONS: Carotid endarterectomy reduced the overall incidence of ipsilateral neurologic events in a selected group of male patients with asymptomatic carotid stenosis. We did not find a significant influence of carotid endarterectomy on the combined incidence of stroke and death, but because of the size of our sample, a modest effect could not be excluded.

Adult↗
PubMed1993

Very distal bypass for salvage of the severely ischemic extremity.

Forty-six bypass grafts to tibial arteries distal to the ankle were performed in 35 patients for salvage of extremities threatened by gangrene or nonhealing ulcers (grade III, category 5) or ischemic rest pain (grade II, category 4). Most patients (80%) were diabetic, with severely calcified arteries, whom previously we would have considered as candidates for primary amputation. All reconstructions were performed with autologous saphenous vein. Inflow was from the common femoral artery in 5 (11%), the popliteal artery in 25 (54%), or the mid-tibial arteries in 16 (35%). Life-table analysis was used to calculate primary patency and limb salvage. Results were analyzed according to origin of inflow, outflow, or configuration of the conduit (in situ saphenous vein, n = 29 [63%], reversed saphenous vein, n = 11 [24%], or nonreversed saphenous vein, n = 6 [13%]). Overall cumulative primary graft patency at 2 years for all grafts was 72%, and the cumulative limb salvage rate was 89% for the same interval. No significant differences were seen in comparing grafts originating from the femoral or popliteal level with those arising from the tibial arteries. No significant differences were noted in graft patency or limb salvage among grafts with a posterior tibial, dorsalis pedis, or plantar artery outflow. No significant difference was noted between in situ saphenous vein grafts and reversed saphenous vein grafts. A significant decreased primary patency was noted for grafts performed with nonreversed, translocated saphenous vein. We conclude that bypass grafts to the ankle or foot vessels are beneficial and should be considered for limb salvage in extremities with gangrene, ischemic ulceration, or ischemic rest pain. In our experience, in situ saphenous vein grafts or reversed saphenous vein grafts performed similarly, whereas nonreversed saphenous vein grafts have a poorer prognosis. Vessel wall calcification requires a modification in technique for performance of these grafts but did not affect long-term performance or limb salvage, and thus should not be considered a contraindication to vascular reconstruction. The operative microscope was used in 61% (28 of 46) of these cases and found useful in creating these delicate anastomoses. Additional follow-up is needed to document the long-term results of these very distal reconstructions.

Adult↗
PubMed1993

Benefit of carotid endarterectomy after prior stroke.

PURPOSE: The benefit of carotid endarterectomy (CEA) in preventing recurrent stroke in patients who have sustained a previous stroke remains controversial. The purpose of this study was to evaluate the immediate results and long-term benefit of CEA after recovery from a prior ipsilateral stroke. METHODS: Between 1980 and 1990, 85 patients underwent CEA for prior stroke with an average follow up of 54 months (range 0.3 to 130). The interval from prior stroke to CEA averaged 19.8 months (range 0.1 to 158.3). Vascular risk factors included hypertension in 70.6%, diabetes in 20.0%, history of smoking in 80.0%, and associated coronary artery disease in 51.8% of the patients. RESULTS: There were no perioperative deaths. Four patients (4.7%) had an ipsilateral stroke within 30 days of operation. During the follow up 31 patients (36.5%) died. The leading cause of death was cardiac (54.8%) followed by cancer (16.1%). By life-table methods, the cumulative incidence of recurrent stroke at 9 years was 14% for strokes in the ipsilateral distribution, for an annual stroke risk of 1.6% per year. The cumulative incidence of stroke in other distributions was 5%, for an annual stroke risk of 2.1% per year for all strokes. When interval to operation, preoperative stroke severity, vascular risk factors, and neurologic symptoms were evaluated, no independent indicator of increased risk of recurrent postoperative stroke could be identified. CONCLUSION: These results demonstrate a marked improvement over the natural history and best medical therapy for these lesions as reoperated in the literature. We conclude that CEA is beneficial in preventing recurrent stroke in this group of patients and should be considered the appropriate management in this setting.

Adult↗
PubMed1993

Predicting complications of carotid endarterectomy.

BACKGROUND AND PURPOSE: Carotid endarterectomy has been shown to be beneficial in patients with high-grade carotid stenosis and ipsilateral transient ischemic attack or stroke. This benefit will be realized only if the operation is performed safely. We sought to determine the extent to which clinically significant adverse events occurring after carotid endarterectomy can be predicted from clinical data available before surgery. METHODS: Eleven hundred sixty patients were randomly selected from all patients who underwent carotid endarterectomy and were discharged during the calendar years 1988, 1989, and 1990 in 12 academic medical centers in 10 states. Clinical data abstracted from hospital charts were analyzed retrospectively. A model was developed and validated to predict the occurrence of stroke, myocardial infarction, or death during the postoperative period of hospitalization. RESULTS: Eight patients (6.9%) suffered at least one adverse event. Rates for individual complications were as follows: death, 1.4%; nonfatal stroke, 3.4%; nonfatal myocardial infarction, 2.1%; and nonfatal stroke or death, 4.8%. Significant predictors of adverse events were age 75 years or older, symptom status (ipsilateral symptoms versus asymptomatic or nonipsilateral symptoms), severe hypertension (preoperative diastolic blood pressure of greater than 110 mm Hg), carotid endarterectomy performed in preparation for coronary artery bypass surgery, history of angina, evidence of internal carotid artery thrombus, and internal carotid artery stenosis near the carotid siphon. The presence of two or more of these risk factors was associated with a nearly twofold increase in risk of an adverse event (relative risk, 1.7; 95% confidence interval, 1.0 to 3.0). CONCLUSIONS: Clinical data can be used to stratify patients undergoing carotid endarterectomy according to risk of postoperative in-hospital stroke, myocardial infarction, or death.

Aged↗
PubMed1993

Carotid endarterectomy for prevention of stroke.

Carotid endarterectomy, a frequently performed operation, has been used as a strategy for preventing stroke in patients with carotid bifurcation disease. The safety and efficacy of the operation were recently challenged by a number of sources. Three major responses to this challenge were to retrospectively review the natural history of carotid bifurcation disease compared with the immediate and long-term results of carotid endarterectomy, to initiate 6 prospective randomized trials to determine the efficacy of carotid endarterectomy for a variety of indications, and to develop appropriateness initiatives and guidelines for using this surgical procedure by organizations concerned with health care policy. I review the current status of these 3 areas of endeavor. In those areas where studies are complete, carotid endarterectomy has been shown to be highly effective in reducing stroke risk. Risk reduction has ranged from 66% to 80% compared with medical management. Based on these sources and findings, I present a list of indications for the operation for surgeons who are able to do the operation safely and within the guidelines established by the Stroke Council of the American Heart Association.

Carotid Artery Diseases↗
PubMed1992

Intraoperative peripheral rotary atherectomy: early and late clinical results.

Early and late clinical results of intraoperative peripheral atherectomy using the Auth Rotablator are analyzed. Twenty patients (15 males and 5 females age 39-89 years, mean 70 years) underwent 25 atherectomy procedures for peripheral arterial occlusive disease from August 1987 to October 1989. All patients underwent serial history, physical exam, and Doppler pressure measurements preoperatively and then postoperatively at 24 hours, one week, one month, and six months during a follow-up period of 15 to 41 months, mean 27 months. Preoperative and intraoperative completion follow-up arteriography was done in all cases and follow-up arteriography in 19 of 25 cases. Initial arteriographic success was achieved in 23/25 (92%) cases and in 39/41 (93%) arterial segments (superficial femoral artery 12/13, popliteal 14/15, tibial 12/13, profunda-femoral 1/1). Complications included intimal dissection (1), equipment breakage (2), minor emboli (3), major emboli with thigh skin loss (1), transient hemoglobinuria (4), wound hematoma (1), wound infection (1), and limb loss (1). Early thrombosis occurred in five cases to give an in-hospital success rate of 18/25 (72%). Primary patency was 66% at six months but only 12% at two years. Rotary atherectomy effectively recanalizes femoral, popliteal and tibial arteries. However, early thromboembolic complications occurred frequently, and the two year patency was dismal. Rotary atherectomy is not recommended for general use until problems of thromboemboli and intimal hyperplasia are solved.

Adult↗
PubMed1992

Standardization of skeletal muscle ischemic injury.

Observations on skeletal muscle function after a timed ischemic interval suggests significant interanimal variability. The purpose of this study is to compare the use of function versus time as a method for standardizing the degree of ischemic injury. Muscle function was measured by recording the isometric contraction to direct supramaximal tetanic stimulation of the anterior tibialis muscle (AT). Muscle cell viability was determined by the reduction of triphenyltetrazolium chloride (TTC)/g tissue measured by a spectrophotometric assay. Twenty-four New Zealand White rabbits underwent an interval of ischemia to one anterior tibialis muscle produced by collateral ligation and unilateral inflow control, using the contralateral AT as a control. The duration of ischemia was determined by one of three methods: Group I, n = 8, underwent ischemia for 3 hr (3 hr); Group II, n = 8, underwent ischemia until AT muscle function decreased to 20% of control (20%); and Group III, n = 8, underwent ischemia until AT muscle function decreased to less than 5% of control (less than 5%). Following the ischemic injury, both physiologic function and cellular viability were measured and expressed as a percentage of control. After 3 hr of ischemia, the mean function was 15.5 with a standard deviation of 20.2, and the TTC reduced/g tissue was 24.7 with a standard deviation of 24.8. When the ischemic interval was determined by a decline of muscle function to 20% of control, the mean TTC reduced was 33.4 +/- 7.6. The mean TTC reduced, when the ischemic interval was terminated when muscle function reached less than 5% of control, was 13.5 +/- 7.2.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Inhibition of intimal hyperplasia by photodynamic therapy using photofrin.

Photodynamic therapy using photofrin and light energy inhibits human myofibroblast proliferation in cell culture. The purpose of this study is to evaluate its influence on intimal hyperplasia in vivo. Twenty New Zealand White rabbits underwent a standardized intimal injury to both common carotid arteries with a 2 Fr balloon catheter. One week later, half of the animals received photofrin (5 mg/kg) intravenously. The remaining 10 rabbits received no photofrin. Two days later, all neck incisions were reopened and a 1-cm segment of each of the 40 carotid arteries was exposed for 5 min to 80 mW of 630 nm light energy from a continuous wave tunable dye laser (fluence = 7.6 J/cm2). All vessels were harvested 5 weeks post-laser treatment following in vivo fixation with formalin. From each artery, separate cross-sections taken from both the lasered and non-lasered regions of each vessel were mounted and stained for histologic evaluation. Analyzed segments were then divided into four different treatment groups: group I segments consisted of arterial cross-sections which were taken from vessel regions that were injured but received neither photofrin nor laser treatment (group I, n = 20); group II segments also did not receive photofrin but were exposed to light energy (group II, n = 20); group III segments received photofrin but no light energy (group III, n = 20); and cross-sections in group IV were taken from those segments which received both photofrin and laser treatment. Using planimetry, the ratio of the area of intimal hyperplasia (IH) to the area enclosed by the internal elastic lamina (IEL) was measured for each specimen (IH/IEL).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Alteration of neutrophil (PMN) function by heparin, dexamethasone, and enalapril.

The aim of this study is to investigate the effect of a seemingly divergent class of pharmacologic agents, each having been reported to suppress intimal hyperplasia, on neutrophil (PMN) function. Human PMNs were isolated and exposed for 30 min to either saline or one of three different pharmacologic agents, each tested at three different concentrations: Group 1, saline (control, n = 14); Groups 2-4, heparin (5000 units, n = 8; 2500 units, n = 6; 1250 units, n = 6) respectively; Groups 5-7, dexamethasone (4 mg, n = 8; 2 mg, n = 6; 1 mg, n = 6), respectively; and Groups 8-10, enalapril (1.25 mg, n = 8; 0.62 mg, n = 6; 0.31 mg, n = 6). Superoxide anion production was measured by the reduction of cytochrome c in a spectrophotometric assay. Chemotaxis was evaluated by the number of PMNs migrating across a filter using a Neuro Probe chamber. Phagocytosis was determined by the ingestion of opsonized zymosan particles by PMNs. Serum obtained from each PMN donor was used both to opsonize the zymosan and as a chemoattractant in the chemotaxis assay. No agent, at any dose, significantly changed superoxide production when compared to control cells. All three agents significantly inhibited PMN chemotaxis at every dose tested (P less than 0.01). In the phagocytosis assay, both heparin (at high and intermediate doses) and enalapril (at all doses) significantly reduced phagocytic activity (P less than 0.01); however, dexamethasone (at high and intermediate doses) produced a marked stimulation (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Anions↗
PubMed1992

Dose responsive suppression of myointimal hyperplasia by dexamethasone.

The effect of increasing doses of dexamethasone on the development of myointimal hyperplasia in the rabbit carotid artery was studied by use of a balloon catheter injury model. Seventy New Zealand white rabbits underwent a standardized 2F balloon catheter stripping of the left carotid intima. The animals were randomly assigned to one of seven groups, each receiving daily injections of either saline (group I, N = 10) or graded doses of dexamethasone: 0.025 mg/kg (group II, N = 10); 0.050 mg/kg (group III, N = 10); 0.075 mg/kg (group IV, N = 10); 0.100 mg/kg (group V, N = 10); 0.125 mg/kg (group VI, N = 10); 0.150 mg/kg (group VII, N = 10). Injections were started 2 days before the intimal injury and continued daily, five times a week, for 8 weeks. The vessels were harvested 12 weeks after injury, and the ratio of the absolute area of intimal hyperplasia to the normalized area enclosed by the internal elastic lamina was measured as an index of myointimal hyperplasia. Also, at the time of harvest, blood flow (ml/min) was measured and the resistance delta P/flow (mm Hg/ml/min) calculated for each vessel in vivo. Twelve-week patency rates were 60% in the control group I, 90% in groups II and III, and 100% in groups IV, V, VI, and VII. The value for the intimal hyperplasia/internal elastic lamina index, expressed as a percent, was 22.2 +/- 3.7 for control group I, 17.7 +/- 2.1 group II, 14.8 +/- 3.0 group III, 12.8 +/- 2.4 group IV, 11.5 +/- 1.8 group V, 5.4 +/- 1.3 group VI, and 3.9 +/- 1.1 for group VII.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1992

Heparin, urokinase, and ancrod alter neutrophil function.

Neutrophils (polymorphonuclear neutrophils [PMNs]) have been implicated as mediators of reperfusion injury. Heparin, urokinase, and ancrod are agents used routinely to prevent and treat thrombosis, yet their effects on PMN function are unknown. Therefore human PMNs were obtained and incubated for 30 minutes with either saline solution or one of the following pharmacologic agents, each tested at three different concentrations: group 1, saline solution (control, n = 14); groups 2 through 4, heparin (5000 units/ml, n = 8; 2500 units/ml, n = 6; and 1250 units/ml, n = 6, respectively); groups 5 through 7, urokinase (50,000 units/ml, n = 8; 25,000 units/ml, n = 6; and 12,500 units/ml, n = 6, respectively), and groups 8 through 10, ancrod (70 units/ml, n = 8; 35 units/ml, n = 6; and 17.5 units/ml, n = 6). Superoxide anion production was measured by the reduction of cytochrome c in a spectrophotometric assay. Chemotaxis was evaluated by the number of PMNs migrating across a filter with a Neuro Probe chamber (Neuro Probe, Cabin John, Md.). Phagocytosis was determined by the ingestion of opsonized zymosan particles by PMNs. Serum obtained from each PMN donor was used both to opsonize the zymosan and as a chemoattractant in the chemotaxis assay. Statistical comparison was evaluated by analysis of variance, and post hoc comparisons for each agent with control were performed with the unpaired Student t test. No agent, at any dose, significantly changed superoxide anion production compared with control cells. All three agents significantly inhibited PMN chemotaxis (p < 0.01). In the control group the number of PMNs counted was 27.6 +/- 4.9.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗