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Introduction: To determine whether the local administration of insulin glargine compared with placebo in nondiabetic patients with venous ulcers (VUs) leads to increased wound healing., Methods: A randomized controlled trial using a split-plot design was performed in 36 adults with leg VUs >25 cm 2 and more than 3 mo of evolution. Each hemi-wound received either 10 UI insulin glargine or saline solution once a day for 7 d. Size of the wounds, thermal asymmetry, the number of blood vessels, and the percentage area of collagen content in wound biopsies were assessed at baseline and after 7 d of treatment. Blood capillary glucose was monitored once a day after the insulin injection., Results: After 7 d of treatment, the hemi-wounds treated with insulin glargine were significantly smaller, had less thermal asymmetry, more blood vessels, and more collagen content than the saline-treated side. Correlation between thermal asymmetry and the number of blood vessels was also found (r 2  = 66.2, P < 0.001). No patient presented capillary glucose levels ≤3.3 mmol/L nor any adverse effects., Conclusions: In nondiabetic patients with chronic VUs, the topical administration of insulin glargine seems to be safe and promotes wound healing and tissue repair after 7 d of treatment., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Despite the established guidelines, there is not a clear consensus about how to manage antiplatelet therapy after carotid surgery. It is a common practice in vascular surgery to use the combination of aspirin and clopidogrel in the treatment of such patients. In this work, we analyzed the impact on long-term survival of antiplatelet therapy in patients treated for carotid stenosis at a single institution over a 10-year period., Methods: Outcomes of 471 patients who underwent carotid intervention (1999-2008) were analyzed. Discharge prescription summaries were retrieved, and patients were divided into two groups according to their antiplatelet regimen: aspirin-only group and aspirin plus clopidogrel group. Only patients with a minimum of 30 days of confirmed antiplatelet therapy were included. All-cause mortality during follow-up represented the primary outcome, whereas stroke and bleeding at 30 days and during follow-up represented secondary end points. When local records were sparse, the Social Security Death Index was queried to confirm mortality. The International Classification of Diseases, 9th Revision (ICD-9 codes), was reviewed for treatment related to a bleeding condition., Results: When divided by indication, there was an increased mortality rate in patients with asymptomatic carotid disease receiving dual antiplatelet therapy as compared with aspirin alone (47% vs 40%; P = .05). Patients with symptomatic carotid disease had a nonsignificant decrease in all-cause mortality if they received dual antiplatelet therapy (38% vs 39%; P = .53). In a subgroup analysis, there was a significant increase in the rate of all-cause mortality among patients older than 75 years receiving dual antiplatelet therapy for asymptomatic carotid disease (82% vs 56%; P = .001), whereas there was a nonsignificant decrease in mortality in patients older than 75 years receiving dual antiplatelet therapy for symptomatic carotid disease (47% vs 63%; P = .50). There was no difference in secondary outcomes (stroke and bleeding) regardless of the indication or the antiplatelet therapy., Conclusions: In this retrospective, single-institution study, the use of dual antiplatelet therapy (aspirin plus clopidogrel) in patients intervened for asymptomatic carotid disease was related to increased all-cause mortality, whereas it did not significantly influence the outcome in patients with symptomatic carotid disease., (Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Objective: To identify risk factors and stratify their effect of compromising 3-year survival in patients treated for asymptomatic carotid disease based upon recently updated guidelines from the Society for Vascular Surgery., Methods: Outcomes of 506 patients who underwent carotid intervention for asymptomatic carotid disease (1999-2008) were analyzed. Hospital computerized medical records were reviewed. When local records were sparse, Social Security Death Index was queried to confirm mortality. Following multivariable Cox regression analysis, a score was assigned based on the calculated hazard ratio (HR) in the following fashion: HR 1.5-1.9 = 1 point; HR 2.0-3.0 = 2 points; and HR >3 = 3 points. The sum of those points comprised the final score for each patient. Kaplan-Meier analyses were then performed to delineate survival differences., Results: Seventy patients (13.83%) did not survive beyond 3 years after the procedure. Age >80 years (HR, 1.79; P = .05; score 1), diabetes mellitus (HR, 1.99; P < .05; score 1), coronary artery intervention (HR, 2.03; P < .01; score 2), severe chronic kidney disease defined as glomerular filtration rate <30 and not on dialysis (HR, 2.46; P = .03; score 2), dialysis patients (HR, 5.67; P = .001; score 3), and chronic obstructive pulmonary disease (HR, 3.53; P < .001; score 3) negatively influenced 3-year survival. Patients with score ≤2 experienced 3-year mortality of 6.0%, whereas score >2 was associated with 31.6% 3-year mortality (HR, 6.10; P < .001). The score value was not associated with the stroke rate at any time point. The resultant score was validated in a separate population of patients with symptomatic carotid disease., Conclusions: This easy predictive score underscores the association of medical risk factors with decreased 3-year survival. This finding may impact future clinical decisions for management of asymptomatic carotid disease., (Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Subclavian Steal Syndrome (SSS) is a fascinating vascular phenomenon in which a steno-occlusive lesion of the proximal subclavian artery causes retrograde flow in the vertebral artery away from the brain stem subsequently causing vertebrobasilar insufficiency. SSS can present with a myriad of neurological and vascular signs and symptoms, but most commonly this phenomenon presents as an incidental finding in an asymptomatic patient., Case Report: Our patient is a 73-year-old female sent to the cardiology clinic for surgical clearance in preparation for an elective cholecystectomy. Shortness of breath was her only complaint. Review of systems was remarkable for left arm pain and blurry vision with repetitive movement. Physical examination noticeable for absence of left radial pulse. Percutaneous angiography demonstrated a totally occulted left subclavian artery with collateral circulation form the vertebrobasilar apparatus., Conclusions: Atypical presentation of this unique entity represents a challenge for physicians who require a high index of suspicion to make the diagnosis. We present an atypical case with radiographical evidence of the steal syndrome, followed by an extensive literature review of the most current diagnostic methods as well as latest recommendations for treatment options and secondary prevention.

Background: Wound morbidity commonly accompanies transposition of the femoral vein when used for hemodialysis access, mainly because of the length of the skin incision. A short incision may reduce wound complications but may compromise the arteriovenous (AV) function because of the shorter length of femoral vein available for puncture. This report presents our experience with a modification of the original technique, in which a smaller skin incision and fistula elevation were used., Methods: The clinical course of 25 AV fistulas in the thigh using the femoral vein was retrospectively analyzed. The original technique to create femoral AV access was used in 12 patients and the modified technique in 13. The procedures were performed between 2005 and 2007, and patients were monitored until January 31, 2011., Results: Three fistulas failed in each group. Five patients in the original group had wound complications. No wound complications occurred in the modified group. The fistula was first used at an average of 10.45 weeks and 6.14 weeks, respectively. Patency was similar in both groups., Conclusions: It is possible to obtain a functional AV fistula in the thigh using the femoral vessels and limiting the extent of the incision. Long-term patency is reasonable, despite the use of a short femoral segment for puncture., (Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

A variety of techniques have been developed to improve the problem with a short renal vein in kidney transplantation. Those techniques range from thorough mobilization of the recipient common and external iliac veins (iliac vein transposition) to donor vein elongation with a saphenous or gonadal vein or a polytetrafluoroethylene graft. Right renal vein extension using the inferior vena cava represents an excellent option for cadaveric kidney transplantation; however, for kidneys from living donors, that is not a suitable alternative. We present two cases where the superficial femoral vein was used as a conduit with good results; there was no additional morbidity for the patient. Although uncommon, renal vein extensions are sometimes needed in kidney transplantation. The superficial femoral vein comes close to representing the ideal conduit for a short renal vein when compared with a synthetic or an autologous graft due to its diameter and harvesting technique.

Ligation for penetrating abdominal vein trauma may have better outcome than a vascular reconstruction in an unstable patient. However, symptoms of chronic venous insufficiency may appear over time. We describe our surgical experience with 4 patients who underwent iliac vein ligation followed by venous bypass with a modified Palma derivation between 48 and 240 hours after sustaining penetrating abdominal trauma with concomitant iliac vein injury. Patients were assessed for venous symptoms and conduit patency with continuous wave Doppler and duplex scanning. One graft occluded acutely and the remaining three remain patent with functioning valves. In order to preserve venous outflow after severe iliac vein injury, we think that venous ligation as a part of damage control surgery followed by a modified Palma operation may prevent chronic symptoms of venous outflow obstruction without compromising an already injured patient.

Background: Low baseline serum hepatitis C virus (HCV)-RNA and clearance of viraemia at week 4 with pegylated interferon (pegIFN) plus ribavirin therapy predict sustained virological response (SVR) and enable a shorter duration of therapy in patients with chronic hepatitis C. It is unclear whether this applies to HIV/HCV-co-infected patients., Patients and Methods: In the Peginterferon Ribavirin ESpaña COinfection (PRESCO) trial, 389 co-infected patients received pegIFN-alpha2a 180 microg/week plus ribavirin 1000-1200 mg/day. Patients with HCV-2/3 were treated for 6 or 12 months, whereas patients with HCV-1/4 were treated for 12 or 18 months. For each genotype, baseline HCV-RNA and rapid virological response (RVR), defined as under 50 IU/ml HCV-RNA at week 4, were evaluated as predictors of SVR in an 'on-treatment' analysis., Results: Overall, SVR was achieved by 193 patients (49.6%), 68/191 (35.6%) with genotype 1, 110/152 (72.4%) with genotypes 2/3 and 15/46 (32.6%) with genotype 4. RVR was the best predictor of SVR regardless of HCV genotype. Only for HCV-1 patients, baseline HCV-RNA less than 500 000 IU/ml was also associated with SVR. In HCV-3 patients RVR had a positive predictive value (PPV) for SVR of 90%, with treatment for 24 or 48 weeks. The PPV of SVR for patients with RVR was 69% for HCV-1 and 83% for HCV-4., Conclusion: Undetectable HCV-RNA at week 4 is the best predictor of curing chronic hepatitis C in HCV/HIV-co-infected patients. In HCV-1 patients, baseline HCV-RNA also predicts response. HIV patients with HCV-3 and RVR may permit shortening therapy duration to only 24 weeks of pegIFN plus 1000-1200 mg ribavirin.

When an autologous vein is not available for lower extremity revascularization, prosthetic grafts are often required. However, prosthetic bypass grafts have limited patency for infrageniculate reconstruction. To potentially improve patency, a new geometric modification of the polytetrafluoroethylene (PTFE) graft, Distaflo (Impra, Tempe, AZ), has been developed for lower extremity bypass. We reviewed our early experience with the Distaflo graft in patients who required infrageniculate bypass for lower extremity ischemia when no suitable autologous saphenous vein was available. All patients were maintained on warfarin anticoagulation postoperatively. All grafts were followed at 6- to 12-week intervals with duplex ultrasound evaluation. Patient characteristics, operative procedures, and graft surveillance information were maintained on a computerized registry. Thirty-two patients with limb-threatening ischemia underwent 35 infrageniculate reconstructions with a Distaflo graft between February 26, 1999, and August 24, 2000. Thirty-two of 35 bypasses were performed on extremities that had previously undergone a surgical procedure. Forty-eight previous revascularization procedures were done on these 25 extremities. Thirty grafts were constructed to the tibial outflow sites, whereas the remaining five grafts were placed to the below-knee popliteal artery. One patient died on the second postoperative day secondary to unrelated causes, and only one graft (3%) failed during the same hospitalization. Fifteen of 35 grafts (43%) remained patent 1 to 30 months later. Four patent grafts (6%) were ligated between 2 and 14 months for infectious indications. When considering the 20 failed grafts, 9 patients underwent major amputation, 5 patients remain with chronically ischemic limbs, and 6 patients underwent additional bypass grafts. Twenty-three patients (72%) maintained limb salvage. The Distaflo PTFE graft achieves promising early patency for complex infrageniculate revascularization and may be used as an alternative conduit in patients with critical limb ischemia who do not have an adequate vein for lower extremity revascularization.

Objective: To evaluate the early results of endovascular grafting for high-risk surgical candidates in the treatment of abdominal aortic aneurysms (AAA)., Summary Background Data: Since the approval of endoluminal grafts for treatment of AAA, endovascular repair of AAA (EVAR) has expanded to include patients originally considered too ill for open AAA repair. However, some concern has been expressed regarding technical failure and the durability of endovascular grafts., Methods: The University of Alabama at Birmingham (UAB) Computerized Vascular Registry identified all patients who underwent abdominal aneurysm repair between January 1, 2000, and June 12, 2002. Patients were stratified by type of repair (open AAA vs. EVAR) and were classified as low risk or high risk. Patients with at least one of the following classifications were classified as high risk: age more than 80 years, chronic renal failure (creatinine > 2.0), compromised cardiac function (diminished ventricular function or severe coronary artery disease), poor pulmonary function, reoperative aortic procedure, a "hostile" abdomen, or an emergency operation. Death, systemic complications, and length of stay were tabulated for each group., Results: During this 28-month period, 404 patients underwent AAA repair at UAB. Eighteen patients (4.5%) died within 30 days of their repair or during the same hospitalization. Two hundred seventeen patients (53%) were classified as high risk. Two hundred fifty-nine patients (64%) underwent EVAR repair, and 130 (50%) of these were considered high-risk patients (including four emergency procedures). One hundred forty-five patients (36%) underwent open AAA repair, including 15 emergency operations. All deaths occurred in the high-risk group: 12 (8.3%) died after open AAA repair and 6 (2.3%) died after EVAR repair. Postoperative length of stay was shorter for EVAR repair compared to open AAA., Conclusions: High-risk and low-risk patients can undergo EVAR repair with a lower rate of short-term systemic complications and a shorter length of stay compared to open AAA. Despite concern regarding the durability of EVAR, high-risk patients should be evaluated for EVAR repair before committing to open AAA repair.

Endovascular therapies are now commonly used in many vascular sites. However, the role for carotid angioplasty and stenting (CAS) remains an unproven therapy with some potential benefits. Initial results of CAS were worse than the surgical standard of carotid endarterectomy (CEA) and did not meet American Heart Association guidelines. However, recent improvements have resulted in improved stroke morbidity rate that may approach that of CEA. Specifically, the embolic problem associated with CAS has been reduced with embolic protection devices, but the ultimate effect of these protection devices remains uncertain. Initial comparison studies of CAS to CEA showed an unacceptably high stroke morbidity rate in the CAS group. As a result, multiple randomized clinical trials have been initiated to compare the results of CAS with embolic protection to that of CEA. While these studies are underway, the authors advocate a careful application of CAS to be used as a complementary tool for the carotid surgeon to use in special circumstances when CEA cannot be undertaken with acceptable morbidity. Furthermore, since the reported stroke morbidity rate of CAS exceeds the AHA recommendation for treatment of asymptomatic patients, most nonsurgical patients with asymptomatic disease should be treated with medical therapy.

Background: Only two aortic stent grafts (Ancure-Guidant, Menlo Park, CA, and AneuRx-Medtronic, Sunnyvale, CA) have been FDA-approved for endovascular aortic aneurysm repair (EndoAAA). These grafts differ significantly in construction and clinical advantage, and combining components of these grafts (hybrid graft) is occasionally necessary. The role and outcome of hybrid aortic stent grafts is unknown., Methods: All EndoAAA procedures during an 18-month period (10/99-4/01) were reviewed using the hospital record and a computer registry. Endografts were classified as hybrid if components from more than one type of stent graft were used or standard if constructed from only one stent graft type. Hybrid grafts were further classified as "anticipated" or "unanticpated." Outcomes were compared between hybrid and standard grafts using Fisher's exact test., Results: One hundred forty-five EndoAAA repairs were performed (AneuRx, 67; Ancure, 70; and custom-made, 8) of which 14 (9.6%) were hybrid grafts. The majority of hybrid grafts (11) were constructed by adding AneuRx aortic or iliac cuffs to Ancure grafts. In most cases, the need for a hybrid graft was unanticipated (10) and related to an intraoperative proximal type I endoleak (7). Conversion to open operation was avoided in six patients by constructing hybrid grafts. When anticipated (4), hybrid grafts were constructed to treat complex iliac aneurysms. Outcomes in all categories were similar (P > 0.05) for hybrid vs standard grafts: technical success (93 vs 99%), conversion toopen AAA (7.1 vs 2.3%), vascular complications (7.1 vs 7.6%), systemic complications (21 vs 11%), endoleak (15 vs 14%), and rupture (0 vs 0%)., Conclusions: The short-term safety and effectiveness of hybrid grafts are similar to those of standard grafts. Combining graft components to create hybrid grafts may increase the ability to treat complex iliac aneurysmal disease and may reduce conversions to open AAA repair. Thus, access to multiple graft types may be an important factor in the success and safety of EndoAAA repair.

Background: The French paradox has been associated with regular intake of red wine, which is enriched with flavonoids. Quercetin, a flavonoid present in the human diet, exerts cardiovascular protection through its antioxidant properties. We hypothesized that the beneficial effect of quercetin also could be related to the inhibition of vascular smooth muscle cell proliferation and migration., Methods: Human aortic smooth muscle cells (AoSMC) were grown in culture in the presence of serum. Quercetin inhibited the serum-induced proliferation of AoSMC. This inhibition was dose-dependent and not attributed to toxicity. Cell cycle analysis revealed that quercetin arrested AoSMC in the G(0)/G(1) phase. The effect of quercetin on AoSMC migration was examined using explant migration and Transwell migration assays. Quercetin significantly decreased migration in both assays in a consistent manner. Finally, Western blot analysis of AoSMC exposed to quercetin demonstrated a significant reduction in the activation of mitogen-activated protein kinase, a signaling pathway associated with the migration of vascular smooth muscle cells., Conclusions: Quercetin inhibits the proliferation and migration of AoSMC, concomitant with inhibition of mitogen-activated protein kinase phosphorylation. These findings provide new insights and a rationale for the potential use of quercetin in the prophylaxis of cardiovascular diseases.

Background: Carotid angioplasty and stenting is under investigation in clinical trials as an alternative to endarterectomy. Some clinicians have hypothesized that stenting would be applicable for patients at high risk who need carotid revascularization. To further test this hypothesis, we stratified our carotid endarterectomy procedures according to current carotid stent protocols., Methods: We reviewed our computerized registry and the clinical charts of patients who underwent carotid endarterectomy. Each procedure was categorized as high risk or low risk, according to the following six separate high-risk factors: 1, severe cardiac dysfunction; 2, the requirement for combined coronary and carotid vascularization; 3, severe pulmonary dysfunction; 4, contralateral internal carotid artery occlusion; 5, previous ipsilateral carotid endarterectomy; and 6, anatomically limited access for carotid endarterectomy. Rates of stroke at 30 days, cardiac complications, and death were tabulated., Results: Between January 1, 1998, and December 31, 2000, 415 carotid endarterectomies were performed on 389 patients. Ninety-eight procedures (23.6%) were classified as high risk on the basis of the following factors: 1, severe cardiac dysfunction (n = 30); 2, requirement for combined coronary and carotid revascularization (n = 14); 3, severe pulmonary dysfunction (n = 8); 4, contralateral carotid occlusion (n = 31); 5, previous ipsilateral carotid endarterectomy (n = 25); and 6, anatomically limited access (n = 4). Seven patients had ipsilateral postoperative strokes (1.7%), with two additional patients having contralateral hemispheric strokes. One patient died from exacerbation of congestive heart failure 9 days after undergoing a second carotid endarterectomy. The total stroke and death rate was 2.6% for all the patients. Two of the 98 procedures in the high-risk group were complicated with ipsilateral stroke (2.0%) as compared with six of the 317 low-risk procedures (1.9%; P = 1). Six procedures were complicated with cardiac dysfunction after surgery, including myocardial infarction, congestive heart failure, or the new onset of atrial fibrillation. Three cardiac complications occurred in the low-risk group (1%), and three occurred in the high-risk group (3.1%; P =.15)., Conclusion: This series shows that patients at high risk can undergo carotid endarterectomy with stroke rates equivalent to the rates of patients at low risk. The cardiac morbidity rate may be increased in the high-risk group. Carotid stenting is unlikely to offer any improvement in stroke risk as compared with carotid endarterectomy, but stenting may reduce non-stroke morbidity rates associated with some high-risk cases.

Background: Endoscopic saphenous vein harvest has been explored as a minimally invasive alternative to a long continuous leg incision for removal of the greater saphenous vein. The endoscopic technique uses limited incisions (2-4) with extended "skin bridges" and videoscopic equipment for the dissection and removal of the greater saphenous vein. This study was undertaken to evaluate the long-term durability of saphenous vein grafts harvested by an endoscopic technique and used for lower extremity arterial revascularization., Methods: All patients who underwent endoscopic saphenous vein harvesting for lower extremity arterial bypass grafting were prospectively followed for graft patency and risk factors. Grafts were surveyed with serial duplex scans at 3- to 6-month intervals over this 5-year study. Life-table methods were used to assess graft survival. A computerized registry and medical records were reviewed to determine graft patency and patient survival., Results: From September 1994 to August 2000, 164 lower extremity arterial saphenous vein grafts harvested by an endoscopic technique were used for lower extremity arterial bypass grafting in 150 patients. The patient population included 111 males (75%) and 112 smokers (75%), but also included a high-risk cohort of 65 diabetic patients (43%) and 15 patients undergoing dialysis/renal transplant (10%). Twenty-eight patients (19%) died within the study period. With life-table methods, 1-, 3-, and 5-year secondary patency rates were 85% (+/- 3.2%), 74% (+/- 5.7%), and 68% (+/- 11.6%). Of the 30 failed grafts, 7 (4%) failed in the first month related to inadequate runoff (4), cardiac instability (2), and an additional surgical procedure (1). Twenty-three grafts (14%) failed between 1 and 42 months. Twenty-two (16%) of these 134 patent grafts underwent a second procedure to maintain patency (13 as primary-assisted patency and 9 as secondary patency)., Conclusions: Endoscopic saphenous vein harvest for lower extremity arterial reconstruction provides a satisfactory conduit for lower extremity bypass grafting. Although increased manipulation from this limited access technique may incite an injury response in the vein, these vein grafts can maintain an adequate patency for lower extremity bypass grafting.

Background: Apoptosis of vascular smooth muscle cells (VSMC) plays a role in physiological vascular remodeling, as well as in disease states such as atherosclerosis and restenosis after angioplasty. Heat shock protein 70 (hsp70) may protect the cell against apoptosis and/or necrosis. In this study, we examined hsp70 expression and its temporal relationship to cell survival or death in a model of intimal vein hyperplasia in vitro., Methods: Segments of human saphenous veins were placed into culture. At different days vein segments were serum-starved or exposed to heat shock. Apoptosis and hsp70 expression were analyzed by Western blot, immunohistochemistry, and TUNEL assay., Results: A marked intimal vein hyperplasia developed after 14 days of culture when compared with baseline. hsp70 was present at baseline and disappeared during culture. Heating during culture could not up-regulate hsp70. The apoptotic markers were absent at baseline and present during normal culture. Conversely, serum starvation stimulated strong hsp70 expression coincidental with the disappearance of apoptotic markers., Conclusions: Stimulation of veins during culture with serum resulted in hyperplasia, apoptosis, and inhibition of hsp70 expression. Down-regulation of hsp70 may permit apoptosis and vessel wall remodeling in this model., (Copyright 2001 Academic Press.)

Background: The optimal time period of antibiotic treatment in secondary peritonitis is still unknown., Aim: To prospectively evaluate: 1) The preferred time period of antibiotic treatment in secondary peritonitis by means of a survey applied to a sample of surgeons, and 2) The outcome of a series of patients with secondary peritonitis in whom the length of antibiotic treatment was based on clinical and laboratory indicators., Patients and Methods: A survey presenting the case of a patient with acute appendicitis and secondary peritonitis was applied to 100 Mexican surgeons. The optimal length of antibiotic treatment in that particular patient was asked. Results were tabulated and analyzed. Subsequently, 35 patients with secondary peritonitis were prospectively evaluated. Antibiotics were discontinued when fever relapsed and the white blood count normalized. Clinical characteristics, diagnosis, surgical treatment and outcome were analyzed. Recurrence of sepsis was investigated as the main outcome variable., Results: The survey revealed that 96% surgeons recommended antibiotic treatment for a period longer than one week. In our study group median age was 33 years, 21 were male and 14 female. All patients had a surgical abdominal condition associated to secondary peritonitis. Median period of antibiotic treatment was 3 days. In a follow-up of one month there was no persistent or recurrent sepsis in any patient., Conclusions: This information may impact in determining the total length of antibiotic therapy if our results are reproduced in studies with more patients.

In order to determine the viability of trophozoites of Acanthamoeba culbertsoni under cryopreservation conditions, cultures in serum-casein-glucose-yeast extract medium were subject to 5%, 7.5%, and 10% concentrations of dimethylsulfoxide (DMSO). With the methodology followed, the percentages of recovery varied between 75.6% and 86.6% with DMSO at 10%, between 54.5% and 73.5% with DMSO at 7.5%, and between 43.6% and 68.5% with DMSO at 5%. The amebae were kept in liquid nitrogen for 30-210 days. The highest viability of trophozoites was founded when DMSO was used at a final concentration of 10% and an equilibrium temperature of 4 C. Gross cultural or morphological changes were not noted in trophozoites thawed from frozen suspensions.

Twenty eight NIH mice were divided into four groups of seven animals each. Mice in groups were injected intraperitoneally with Freund's complete adjuvant (FCA), Concanavalin A (Con A), Equimune (EI) and phosphate buffered saline (PBS), respectively, 7 days before infection with 300 Trichinella spiralis infective larvae per animal. Forty two days after infection all mice were sacrificed and processed by artificial digestion to determine the number of larvae per gram (LPG) of muscle tissue. The mean +/- SD of LPG obtained were 59.8 +/- 13.1, 17 +/- 8.5, 3.3 +/- 6.2 and 71 +/- 11.5 for groups FCA, Con A, EI, and PBS, respectively. Significant reductions in larvae worm numbers, compared with non-treated controls, were 76% and 95.3% in groups Con A and EI, respectively.