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C B Anderson

Publications and source records attributed to C B Anderson.

At least 37 records · Page 2Linked to original sources
PubMed1994

Long-term effectiveness of extraanatomic renal artery revascularization.

BACKGROUND: The efficacy of direct aortorenal bypass and renal artery endarterectomy are well established. The purpose of this study is to define better the results of extraanatomic renal revascularization procedures. METHODS: From April 1987 to March 1993, 124 patients underwent renal artery revascularization. Forty-eight (39%) of them (33 women, 15 men; average age, 65.9 years) underwent 49 extraanatomic renal artery bypasses. Preoperative risk factors included smoking in 30 patients (61%), history of myocardial infarction in 14 (29%), diabetes mellitus in 11 (22%), congestive heart failure in nine (18%), chronic obstructive pulmonary disease in 11 (22%), and stroke in six (12%). The average creatinine level was 2.3 mg/dl. The average number of antihypertensive medications was 2.4. Thirty iliorenal, 10 gastroduodenal-renal, seven hepatorenal, and two splenorenal bypasses were performed together with 10 contralateral nephrectomies. RESULTS: Six major postoperative complications occurred. There were no deaths. Forty-one (85%) of patients had improvement or cure of their hypertension. Seven (15%) of patients failed to respond to treatment, and three required subsequent nephrectomy. After operation the average creatinine level was 1.7 mg/dl and the average number of medications was 1.7. Mean follow-up period has been 23.2 months (range, 1 to 79 months). CONCLUSIONS: Extraanatomic bypass proved to be efficacious in treating hypertension and preserving renal function and has an acceptable rate of morbidity and mortality. We conclude that these procedures are an acceptable alternative to direct aortorenal artery revascularization.

Aged↗
PubMed1994

Effects of the arachidonate 5-lipoxygenase synthesis inhibitor A-64077 in intestinal ischemia-reperfusion injury.

This study was designed to characterize the role of arachidonate 5-lipoxygenase metabolism during experimental intestinal ischemia-reperfusion (I/R) injury. Canines were subjected to 3 hr of intestinal ischemia followed by 1 hr of normobaric reperfusion. Intestinal ischemia followed by 1 hr of normobaric reperfusion. Intestinal mucosal leukotriene B4 and leukotriene C4 synthesis tripled after ischemia and ischemia-reperfusion, relative to non-ischemic intestinal mucosa. The flux of fluid and protein from the capillary to the lumen also increased 3-fold after I/R. The selective 5-lipoxygenase synthesis inhibitor A-64077 (Ziluten, 5 mg/kg, p.o.) abolished I/R-induced leukotriene synthesis and reduced transluminal protein flux (50%) but did not influence the lumenal accumulation of fluid after I/R. In animals treated with the leukotriene synthesis inhibitor, intestinal vascular resistance significantly declined during the imposed ischemia period and after 60 min of reperfusion. Mucosal myeloperoxidase activity, a biochemical marker for tissue neutrophils, rose significantly after I/R, and these increases were prevented with the 5-lipoxygenase synthesis inhibitor. In other experiments, the lipoxygenase inhibitor nondihydroguaretic acid produced similar results to those of A64077. In an attempt to determine the source of mucosal leukotrienes during intestinal I/R, we imposed in vitro ischemia and reperfusion on normal mucosal tissue in a blood-free environment. Mucosal tissue was incubated in Krebs buffer under oxygen for 3 hr to simulate the control condition, under nitrogen for 3 hr to simulate ischemia and under nitrogen for 2 hr followed by oxygen for 1 hr to simulate I/R.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Characterization of platelet-activating factor receptors on canine T lymphocytes.

The ability of purified canine T lymphocytes to selectively bind platelet activating factor (PAF) was characterized. Authentic radiolabeled PAF rapidly and selectively bound to T lymphocytes and reached saturation within 1 min. This binding was reversible and highly selective for (R) PAF because (S) PAF, lyso-PAF, and diacyl PAF did not displace the bound (R) PAF probe. Only increasing quantities of chemically pure (R) PAF displaced the radiolabeled (R) PAF probe. The binding maximum of PAF was determined to be 35 pM per 2 x 10(6) lymphocytes. Competitive radioligand binding studies and Scatchard analysis indicated a single class of high affinity receptors with a dissociation constant of 0.077 nM and a receptor density of 6419 receptors per cell. The ability of purified canine T lymphocytes to hydrolyze PAF to the biologically inactive metabolite lyso-PAF was also studied. Over a 30-min incubation period, about 5% of PAF was metabolized to lyso PAF. This rate of PAF hydrolysis was the same as the rate observed with the media without cells, suggesting a small degree of nonenzymatic hydrolysis. The effects of varying concentrations of authentic PAF on intracellular free Ca2+ release in purified T lymphocytes was evaluated using the fluorescent probe Fura-2 and excitation-emission spectrofluorometry. PAF below the concentration of 1.0 nM did not significantly increase intracellular Ca2+ in T lymphocytes. More than 1 nM PAF, intracellular-free Ca2+ modestly, but significantly, increased in T lymphocytes. In other experiments, canine PBMC proliferated in response to Con A and in the one way MLR. These proliferative responses were abolished when the selective PAF receptor antagonist SC-47014A was added to the culture medium. In the MLR, this inhibitory effect was dependent on the length of time that the antagonist was in the culture. Specifically, inhibition of proliferation was incrementally reversed when the PAF antagonist was introduced progressively later into the 7-day MLR stimulation period, suggesting that PAF receptor blockade prevents an MLR response from occurring, but is unable to suppress an existing MLR response. Although the Con A-induced mononuclear cell proliferation was abolished with PAF receptor antagonists, the addition of authentic biologically active PAF or PAF analogs did not alter the proliferative response to Con A. In conclusion, canine T lymphocytes possess high affinity receptors for PAF. These binding sites are highly selective and reversible. PAF binding slightly increases intracellular free Ca2+ in T lymphocytes and appears to be involved in lymphocyte proliferation in response to soluble plant mitogen and alloantigen.

Animals↗
PubMed1993

Long-chain acyl-coenzyme A thioesters and renal hypothermic ischemic injury: effects of glycine flush.

The effects of hypothermic ischemia utilizing Euro-Collins flush on renal tissue long-chain activated fatty acid content was studied in dogs. Also, the ability of the simple amino acid glycine to complex these acyl thioesters was also investigated. Renal inner cortex was found to contain (in increasing amounts) myristoyl-, palmitoleoyl-, palmitoyl-, arachidonyl-, and oleoyl-coenzyme A throughout the 3 days of cold ischemia. Although the amounts of individual long-chain acyl-CoA compounds varied considerably, the concentrations were not found to differ significantly with increasing ischemia times. The presence of 5 mM of glycine in the flush also did not influence the amount or species of long-chain acyl-CoA esters in renal tissue during cold ischemia. Ischemic renal tissue content of most long-chain acyl-CoA compounds was reduced by about 50% when the tissue underwent in vitro reperfusion with 37 degrees C O2-saturated media. Glycine included in the flush storage solution did not alter acyl-CoA levels in tissue undergoing hypothermic ischemia and short-term in vitro reperfusion with O2-saturated buffer. In conclusion, long-chain acyl-CoA thioesters are present during hypothermic renal ischemia and the levels of most of these species are reduced during in vitro reperfusion after ischemia. The quality and production mass of these metabolites appears to be unaltered by progressive hypothermic ischemia times. Finally, the protective effects of glycine in this model of renal organ preservation injury are not associated with reductions of renal tissue long-chain activated fatty acids.

Acyl Coenzyme A↗
PubMed1993

Simultaneous surgical management of aortic and renovascular disease.

The results of simultaneous elective infrarenal aortic reconstruction and renovascular surgery were retrospectively reviewed in 102 patients who consecutively underwent operation. The perioperative mortality rate (0 to 54 days) was 5% (5 of 102). Renal function had returned to baseline or was improved at discharge in 89 of 97 (92%) surviving patients. The intraoperative use of renal hypothermia was an independent predictor of improved postoperative renal function, by multivariate analysis. Twenty-five of 29 (86%) patients with severe hypertension had improvement in their blood pressure on the same or fewer medications postoperatively (p = 0.0005). A retroperitoneal incision was associated with less intraoperative crystalloid fluid administration (p = 0.03), more rapid postoperative resumption of an oral diet (p = 0.04), and better long-term survival (p = 0.02) when compared with a transperitoneal incision. We conclude that the simultaneous repair of infrarenal aortic pathology and renovascular lesions is associated with an acceptable perioperative morbidity and preserves or improves renal function in the majority of patients. The frequent use of renal hypothermia and careful consideration of the route of operative exposure will lead to optimal results.

Aged↗
PubMed1993

Preservation of renal function in juxtarenal and suprarenal abdominal aortic aneurysm repair.

PURPOSE: Deterioration in renal function is a common cause of morbidity in patients treated surgically for juxtarenal and suprarenal abdominal aortic aneurysms. We reviewed our experience over the last 8 years with 65 consecutive patients undergoing juxtarenal (n = 31) or suprarenal (n = 34) abdominal aortic aneurysm repair. METHODS: The aneurysms were repaired with a transabdominal (n = 8), thoracoabdominal (n = 4), retroperitoneal (n = 22), or thoracoretroperitoneal (n = 31) approach. Proximal aortic clamps were placed at the suprarenal, supra-superior mesenteric artery, or supraceliac level. Renal hypothermia with cold heparinized saline solution renal artery perfusion was used to protect renal function in 38 patients with either preoperative renal insufficiency or with anticipated prolonged renal ischemia (> 30 minutes). Concomitant renal artery reconstruction was required in 30 patients. RESULTS: Significant operative morbidity developed in 23 (35.3%) patients. There was one (1.53%) perioperative death (0 to 90 days). Temporary dialysis was necessary in two patients. Preoperative renal insufficiency was a significant risk factor on multivariate analysis for a decline in renal function during the first postoperative week. However, serum creatinine concentration had returned to baseline or improved in all patients but two (3.1%) at the time of discharge. In spite of significantly longer renal ischemia, discharge creatinine levels were, on univariate analysis, statistically less than baseline creatinine levels in patients with suprarenal aneurysms, patients requiring renal reconstruction, and patients treated with renal hypothermia. The location of the proximal aortic clamp was not a factor in postoperative morbidity. There was no significant difference between juxtarenal and suprarenal aneurysms with respect to operating room time, transfusion requirements, days intubated, resumption of oral diet, or the length of hospitalization. CONCLUSIONS: Careful consideration of the route of exposure, location of the proximal aortic clamp, and the preservation of renal function with renal hypothermia and with the repair of significant renal artery lesions will result in minimal morbidity and mortality in patients requiring surgery for juxtarenal or suprarenal abdominal aortic aneurysms.

Aged↗
PubMed1992

Improved and simplified tissue extraction method for quantitating long-chain acyl-coenzyme A thioesters with picomolar detection using high-performance liquid chromatography.

A method has been developed that permits rapid and easy tissue extraction of long-chain acyl-coenzyme A (acyl-CoA) thioesters with sensitive quantitation by reversed-phase high-performance liquid chromatography (RP-HPLC). Tissue homogenants are extracted using a reserve Bligh-Dyer technique, and long-chain acyl-CoA esters are harvested in the methanolic aqueous phase. Complex lipids and phospholipids are removed in the chloroform-rich organic Bligh-Dyer second phase, and long-chain acyl-CoA compounds are further purified from the methanolic aqueous Bligh-Dyer first phase on C18 extraction columns after removal of the methanol. The eluted and purified acyl-CoA esters are then quantitated by RP-HPLC using heptadecanoyl-CoA as an internal standard resulting in a detector sensitivity of about 12 pmol. Ten long-chain acyl-CoA esters from C12:0 to C20:4 were identified and separated from canine renal cortex and murine liver samples. The predominant acyl-CoA peaks from both kidney and liver were 14:0, 16:1, 16:0, 18:1, 18:2 and 20:4. Murine liver also produced 18:0 and all peaks disappeared after alkaline hydrolysis of the samples. This extraction and quantitation technique can successfully be used for tissue samples as small as 20 mg, and many samples can be processed in a short period of time. The simplicity of the extraction procedure and the sensitivity of the assay make this an attractive alternative approach to quantitating long-chain acyl-CoA thioesters from complex biological samples such as tissues.

Acyl Coenzyme A↗
PubMed1992

Transvenous retrieval of misplaced stainless steel Greenfield filters.

Transvenous retrieval was attempted in five patients following surgical misplacement of stainless steel Greenfield filters. Four filters were located within the right atrium, and one was in the left hepatic vein. All retrievals were attempted within 5 days of placement. Retrieval was successful for the four filters in the right atrium and failed for the filter in the left hepatic vein. One air embolism occurred; this was the only filter- or retrieval-related complication. Transvenous retrieval is a safe and effective minimally invasive method of removing misplaced filters.

Female↗
PubMed1992

Detection of the source of arterial emboli by transesophageal echocardiography: a case report.

We report a case acute lower extremity ischemia caused by emboli in which the initial diagnostic evaluation, including standard aortoiliofemoral arteriography and routine transthoracic two-dimensional echocardiography, failed to reveal the offending source. Because of the strong clinical suspicion that the origin of the arterial occlusion was embolic, transesophageal echocardiography was performed. Transesophageal echocardiography demonstrated an aortic valvular lesion and cardiac surgery was performed on an emergency basis. The use of transesophageal echocardiography in evaluating the heart and thoracic aorta as a source of distal emboli is also discussed.

Aortic Valve↗
PubMed1992

Selective loss of functional antidonor cytolytic T cell precursors following donor-specific blood transfusions in long-term renal allograft recipients.

Pretransplant administration of donor-specific blood transfusions prolongs the survival of HLA-disparate renal allografts to a level comparable to that of HLA-identical transplants. To test the hypothesis that DST recipients develop immunologic tolerance of their donors, we examined antidonor T cell immunity in a group of DST recipients with long-term well-functioning allografts. Limiting dilution analysis studies indicated that 5/14 long-term DST recipients exhibit a complete absence of detectable antidonor cytolytic T lymphocyte precursors (CTLp). In contrast, 4/4 long-term non-DST recipients who received conventional or cyclosporine immunosuppression exhibited significant levels of antidonor CTLp. Nonresponsive DST recipients retained the capacity to mount antidonor responses in mixed lymphocyte reactions and IL-2 production assays, and exhibited normal levels of CTLp directed to third-party antigens. Addition of exogenous IL-2 to cell-mediated lympholysis cultures did not restore antidonor CTL responses. In summary, our data suggest that the DST conditioning regimen induces a complete yet selective loss of functional antidonor CTLp in some long-term renal transplant recipients.

Blood Transfusion↗
PubMed1992

An embolizing lesion in a minimally diseased aorta.

A case report of a patient with an unusual source of emboli resulting in acute limb-threatening ischemia is presented. Diagnostic angiography of the lower extremity was performed, followed by thromboembolectomy, which successfully restored normal arterial flow to the threatened leg. After surgery the patient underwent transesophageal echocardiography, which failed to identify an embolic source. Because of the high degree of clinical suspicion that the primary disease process was embolic rather than thrombotic, a thorough evaluation of the arterial tree was performed, including computed tomography and aortography. A large, mobile intravascular lesion arising from a normal descending thoracic aorta was identified and successfully treated with resection and graft placement.

Angiography, Digital Subtraction↗
PubMed1992

In situ saphenous vein for lower extremity revascularization.

BACKGROUND: During a 6-year period, 349 in situ saphenous vein bypass grafts were performed for limb salvage by three surgeons. METHODS: Outflow anastomoses were constructed to the infrageniculate popliteal (25%), posterior tibial (20%), peroneal (20%), anterior tibial (19%), and dorsal pedal arteries (7%). Mean patient age was 70 1/2 years. RESULTS: The 30-day mortality rate was 3.2%, and 19% died during the ensuing 68-month interval. At 1, 24, and 60 months primary graft patency was 89%, 77%, and 74%, secondary graft patency was 91%, 80%, and 78%, and cumulative limb survival was 94%, 88%, and 84%, respectively. Cumulative patency rates at 60 months depending on outflow site were as follows: popliteal (85%), anterior tibial (80%), posterior tibial (70%), dorsal pedal (68%), and peroneal (60%). Patency at the peroneal position was significantly inferior to that of other infrapopliteal sites combined (p less than 0.05). Cumulative limb survival at 60 months, according to outflow site, was as follows: popliteal (95%), anterior tibial (85%), posterior tibial (78%), dorsal pedal (73%), and peroneal (67%). There was no significant difference in limb salvage among infrapopliteal outflow sites. However, patency rates and limb salvage were significantly better for the popliteal outflow site than the infrapopliteal outflow sites (p less than 0.01). CONCLUSIONS: (1) A 5-year graft patency rate of 78% and a limb salvage rate of 84% are achievable, (2) peroneal bypass is associated with a lower rate for graft patency but not limb salvage, and (3) popliteal bypass has the best graft patency and limb salvage rates.

Aged↗
PubMed1991

Protective effects of glycine during hypothermic renal ischemia-reperfusion injury.

The objective of this investigation was to test the effects of glycine, a cytoprotectant in normothermic in vitro models of renal ischemia, in a model of hypothermic renal preservation injury. This study also probes possible physiological mechanisms of glycine protection during renal hypothermic ischemia-reperfusion injury. Canine kidneys were subjected to 48 h of hypothermic ischemia (4 degrees C) after intravascular flush with cold conventional Collins solution (G. H. Collins, M. B. Bravo-Shugarman, and P. I. Terasaki, Lancet 2: 1219-1223, 1969) and were subsequently revascularized for 1 h. After 1 h of reperfusion, glomerular filtration rate, urine production, and electrolyte excretion were dramatically higher when the Collins flush contained 5 mM glycine, compared with the 0 mM glycine controls. Renal tissue adenine nucleotides and glutathione levels progressively declined with graded cold ischemia times, and glycine had no effect on these levels. However, renal tissue ATP levels (but not glutathione) were significantly higher when kidneys were flushed with glycine, stored for 48 h, and reoxygenated in vitro for 1 h at 37 degrees C, compared with kidneys flushed without glycine. Analysis of CoA esters from ischemic renal tissue indicated altered production of only butyryl CoA after 48 and 72 h of cold ischemia, but no differences were detected in glycine or control kidneys. In conclusion, this study reports dramatic functional preservation with glycine in kidneys subjected to hypothermic ischemia and in vivo reperfusion. The mechanisms of these effects appear not to be attributable to the maintenance of cellular adenine nucleotide or glutathione levels nor to the scavenging of accumulated amphipathic acyl CoA esters.

Acetyl Coenzyme A↗
PubMed1990

Prostanoids and hypothermic renal preservation injury.

The effect of 48 hours of hypothermic renal ischemia utilizing Euro-Collins flush and short term reperfusion on renal prostaglandin synthesis was studied in dogs. Hypothermic ischemia followed by 60 minutes of reperfusion in-vivo resulted in significant elevations in renal Thromboxane B2 (TXB2) production in the outer cortex, inner cortex, and medulla, relative to non-ischemic kidneys. Prostaglandin E2 (PGE2) and 6-keto Prostaglandin F1 alpha (6-K PGF1 alpha) production were not significantly affected by ischemia and reperfusion. Enhanced TXB2 production was not seen with ischemia alone (without reperfusion) or with reperfusion with O2 saturated buffer, indicating a blood born source or stimuli. Early postreperfusion renal blood flow after hypothermic ischemia followed a biphasic pattern; blood flow increased for the first 10 minutes of reperfusion to achieve normal values, and then steadily declined over the next 20 minutes. This pattern was not altered by the cyclooxygenase inhibitors Idomethacin (5 mg/kg, P.O.) or Mefenamic acid (10 mg/kg, I.V.). Administration of the TXA2 synthesis inhibitor CGS-12970 (3 mg/kg, I.V.) or the TXA2/endoperoxide receptor antagonist SQ-29548 (80 micrograms/min, I.A.) significantly increased renal blood flow during reperfusion but neither agent altered the basic time dependent pattern observed in the control group. These data indicate that 48 hours of hypothermic renal ischemia results in dramatic changes in intrarenal TXA2 synthesis at the time of reperfusion. Enhanced TXA2 production is not dependent on reoxygenation per se, but rather requires reperfusion with blood suggesting a circulatory source.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Vascular access in patients with arterial insufficiency. Construction of proximal bridge fistulae based on inflow from axillary branch arteries.

Patients with renal failure and underlying peripheral vascular disease pose a difficult management problem in establishing long-term angioaccess for chronic hemodialysis. This report summarizes our experience with five debilitated patients who developed acute upper extremity ischemia after forearm fistula construction corrected by fistula ligation. Successful angioaccess was achieved without ischemia recurrence by construction of proximal bridge fistulae with arterial inflow based on branch arteries of the axillary artery. The relatively small size of the branch vessel was the main factor in limiting fistula flow while permitting normal distal axillary artery flow. In four patients direct fistula flow measurements ranged from 200 mL per minute to 620 mL per minute. Axillary arterial flow distal to the fistula ranged from 120 to 200 mL per minute and did not significantly change after fistula construction or during temporary occlusion of the fistula. Four of the five patients continue to dialyze uneventfully from 4 to 8.5 months. One patient died after discontinuation of dialysis 1 month after operation.

Aged↗