Recombinant Cysteine Proteinase B from Leishmania braziliensis and Its Domains: Promising Antigens for Serodiagnosis of Cutaneous and Visceral Leishmaniasis in Dogs.

Leishmaniasis represents a group of parasitic diseases caused by a protozoan of the genus Leishmania and is widely distributed in tropical and subtropical regions. Leishmaniasis is one of the major tropical neglected diseases, with 1.5 to 2 million new cases occurring annually. Diagnosis remains a challenge despite advances in parasitological, serological, and molecular methods. Dogs are an important host for the parasite and develop both visceral and cutaneous lesions. Our goal was to contribute to the diagnosis of canine cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL) using the recombinant cysteine proteinase B (F-CPB) from Leishmania braziliensis and its N- and C-terminal domains (N-CPB and C-CPB) as antigens in an enzyme-linked immunosorbent assay (ELISA). Sera from dogs from Northwest Argentina diagnosed with CL were tested by ELISA against a supernatant of L. braziliensis lysate, the F-CPB protein, and its domains. We found values of sensitivity (Se) of 90.7%, 94.4%, and 94.3% and specificity (Sp) of 95.5%, 90.9%, and 91.3% for F-CPB and its N- and C-terminal domains, respectively. In sera from dogs diagnosed with VL from Northeast Argentina, we found Se of 93.3%, 73.3%, and 66.7% and Sp of 92.3%, 76.9%, and 88.5% for F-CPB and its N- and C-terminal domains, respectively. These results support CPB as a relevant antigen for canine leishmaniasis diagnosis in its different clinical presentations. More interestingly, the amino acid sequence of CPB showed high percentages of identity in several Leishmania species, suggesting that the CPB from L. braziliensis qualifies as a good antigen for the diagnosis of leishmaniasis caused by different species.

The TcTASV proteins are novel promising antigens to detect active Trypanosoma cruzi infection in dogs.

In regions where Chagas disease is endemic, canine Trypanosoma cruzi infection is highly correlated with the risk of transmission of the parasite to humans. Herein we evaluated the novel TcTASV protein family (subfamilies A, B, C), differentially expressed in bloodstream trypomastigotes, for the detection of naturally infected dogs. A gene of each TcTASV subfamily was cloned and expressed. Indirect enzyme-linked immunosorbent assays (ELISA) were developed using recombinant antigens individually or mixed together. Our results showed that dogs with active T. cruzi infection differentially reacted against the TcTASV-C subfamily. The use of both TcTASV-C plus TcTASV-A proteins (Mix A+C-ELISA) enhanced the reactivity of sera from dogs with active infection, detecting 94% of the evaluated samples. These findings agree with our previous observations, where the infected animals exhibited a quick anti-TcTASV-C antibody response, coincident with the beginning of parasitaemia, in a murine model of the disease. Results obtained in the present work prove that the Mix A+C-ELISA is a specific, simple and cheap technique to be applied in endemic areas in screening studies. The Mix A+C-ELISA could help to differentially detect canine hosts with active infection and therefore with high impact in the risk of transmission to humans.

A review of antithrombotic therapy and the rationale and design of the randomized edoxaban in patients with peripheral artery disease (ePAD) trial adding edoxaban or clopidogrel to aspirin after femoropopliteal endovascular intervention.

Compared with the coronary setting, knowledge about antithrombotic therapies after endovascular treatment (EVT) is inadequate in patients with peripheral artery disease (PAD). Based on a review of trials and guidelines, which is summarized in this article, there is scant evidence that antithrombotic drugs improve outcome after peripheral EVT. To address this knowledge gap, the randomized, open-label, multinational edoxaban in patients with Peripheral Artery Disease (ePAD) study (ClinicalTrials.gov identifier NCT01802775) was designed to explore the safety and efficacy of a combined regimen of antiplatelet therapy with clopidogrel and anticoagulation with edoxaban, a selective and direct factor Xa inhibitor, both combined with aspirin. As of July 2014, 203 patients (144 men; mean age 67 years) from 7 countries have been enrolled. These patients have been allocated to once-daily edoxaban [60 mg for 3 months (or 30 mg in the presence of factors associated with increased exposure)] or clopidogrel (75 mg/d for 3 months). All patients received aspirin (100 mg/d) for the 6-month duration of the study. The primary safety endpoint is major or clinically relevant nonmajor bleeding; the primary efficacy endpoint is restenosis or reocclusion at the treated segment(s) measured at 1, 3, and 6 months using duplex ultrasound scanning. All outcomes will be assessed and adjudicated centrally in a masked fashion. The ePAD study is the first of its kind to investigate a combined regimen of antiplatelet therapy and anticoagulation through factor Xa inhibition with edoxaban.

The quality of life in patients after peripheral bypass surgery deteriorates at long-term follow-up.

OBJECTIVE: We aimed to study the long-term development of health-related quality of life (HR-QoL) in patients with peripheral arterial disease after they underwent peripheral bypass surgery and to evaluate the influence of adverse vascular events that occurred during follow-up. METHODS: We compared current HR-QoL scores with previous measurements in patients who participated in the Dutch Bypass and Oral Anticoagulants or Aspirin (BOA) Study between 1995 and 1998 after they underwent infrainguinal bypass surgery. Patients from six centers that contributed most to the Dutch BOA Study (n = 482) were followed up retrospectively from 1995 up to 2009. RESULTS: At a mean follow-up of 11 years since BOA randomization, 165 of the 482 patients were alive of whom 123 (75%) completed the EQ-5D and RAND-36 questionnaires. Fifty-three patients completed the questionnaires three times: at BOA entry, at BOA close-out, and at BOA long-term follow-up. In these patients the HR-QoL scores decreased over time, especially for the physical health dimension. In comparison with the general population, matched for age and gender, the HR-QoL scores at both BOA entry and long-term follow-up were substantially lower, even if the patient's graft was patent and no other vascular events had occurred. The occurrence of an adverse vascular event worsened the physical health state further. CONCLUSIONS: The physical HR-QoL in patients with peripheral arterial disease (PAD) after peripheral bypass surgery was highly impaired, independent of graft patency, and deteriorated further over time. An adverse vascular event worsened the physical health state and underlined the importance of atherosclerotic risk management as well as stimulation of physical activity in patients with peripheral arterial disease to preserve HR-QoL.

Bleeding increases the risk of ischemic events in patients with peripheral arterial disease.

BACKGROUND: Patients with peripheral arterial disease are at high risk of ischemic events and therefore are treated with antithrombotics. In patients with coronary artery disease or cerebrovascular disease, bleeding is related to the subsequent occurrence of ischemic events. Our objective was to assess whether this is also the case in patients with peripheral arterial disease. METHODS AND RESULTS: All patients from the Dutch Bypass and Oral Anticoagulants or Aspirin (BOA) Study, a multicenter randomized trial comparing oral anticoagulants with aspirin after infrainguinal bypass surgery, were included. The primary outcome event was the composite of nonfatal myocardial infarction, nonfatal ischemic stroke, major amputation, and cardiovascular death. To identify major bleeding as an independent predictor for ischemic events, crude and adjusted hazard ratios with 95% confidence intervals were calculated with multivariable Cox regression models. From 1995 until 1998, 2650 patients were included with 101 nonfatal major bleedings. During a mean follow-up of 14 months, the primary outcome event occurred in 218 patients; 22 events were preceded by a major bleeding. The mean time between major bleeding and the primary outcome event was 4 months. Major bleeding was associated with a 3-fold increased risk of subsequent ischemic events (crude hazard ratio, 3.0; 95% confidence interval, 1.9 to 4.6; adjusted hazard ratio, 3.0; 95% confidence interval, 1.9 to 4.7). CONCLUSIONS: In patients with peripheral arterial disease, as in patients with coronary artery disease or cerebrovascular disease, major bleeding was independently associated with major ischemic complications. Without compromising the benefits of antithrombotics, these findings call for caution relative to the risks of major bleeding.

Effect of ximelagatran on ischemic events and death in patients with atrial fibrillation after acute myocardial infarction in the efficacy and safety of the oral direct thrombin inhibitor ximelagatran in patients with recent myocardial damage (ESTEEM) trial.

BACKGROUND: New-onset trial fibrillation (AF) occurs commonly after acute myocardial infarction (MI) and is associated with a poor prognosis due to stroke or death. The optimal antithrombotic therapy is unknown. The aim of this study was to investigate whether an oral direct thrombin inhibitor, ximelagatran, added to aspirin, reduced the risk of death, myocardial infarction (MI), and stroke in patients who developed AF after their qualifying MI in the efficacy and safety of the oral direct thrombin inhibitor ximelagatran in patients with recent myocardial damage (ESTEEM) trial. METHODS: The ESTEEM trial evaluated 6 months treatment with ximelagatran together with aspirin, compared to aspirin alone, for prevention of ischemic events in 1883 patients randomized within 14 days after an MI. After their qualifying MI, 174 (9%) patients developed AF in hospital. Multivariate hazard ratios for ximelagatran compared with placebo were calculated by presence AF. RESULTS: Of 101 patients with AF treated with ximelagatran 7 (6.9%) had either death, MI, or stroke, compared with 15 (20.6%) in 73 patients allocated to placebo. Ximelagatran reduced the risk of death, MI, or stroke by 70% (hazard ratio 0.30, 95% CI 0.12-0.74). For the separate outcome events, we found similar, nonsignificant trends. One major bleeding event occurred in each treatment group. CONCLUSIONS: For patients with MI complicated by AF, the combination of aspirin and an oral direct thrombin inhibitor seems beneficial. The high risk for death, MI, and stroke in this population and the increasing use of percutaneous interventions in MI patients may suggest a combination of long-term antiplatelet and anticoagulant therapy. Randomized clinical trials are warranted.

Aortic venting. Comparison of vent effectiveness.

Three commercially available aortic vents have been evaluated as to effectiveness in removing small volumes of air introduced into a mock circulatory circuit. Without aspiration, Vent 2 was the most effective and removed 58 per cent of 0.1 ml., 90 per cent of 0.5 ml., and 74 per cent of 1.0 ml. boluses at a cardiac output of 2 L. At a cardiac output of 4 L., Vent 2 removed 42, 76, and 49 per cent, respectively. With aspiration (Vent 2 not designed for aspiration) and a 2 L. cardiac output, Vents 1 and 3 removed 84 to 98 per cent of 0.1 ml., 68 to 92 per cent of 0.5 ml., and 74 to 86 per cent of 1.0 ml. boluses. With aspiration and a 4 L. cardiac output, Vent 3 was significantly more effective than Vent 1 and removed 92 to 94 per cent of 0.1 ml., 82 to 86 per cent of 0.5 ml., and 77 to 80 per cent of 1.0 ml. boluses. One liter of canine blood was aspirated through Vents 1 and 3 and a flow rate of 250 ml. per minute. For Vent 1, serum hemoglobin levels increased from 40 to 249 mg. per 100 ml. and for Vent 3 from 49 to 212 mg. per 100 ml. There are significant differences in the ability of commercially available aortic vents to remove small air bubbles trapped in the heart after initial direct cardiac venting. Vents having the capability of aspiration are more effective and result in acceptable hemolysis.

The Blalock-Taussig shunt in the first six months of life.

Because of increasing interest in the application of the Blalock-Taussig shunt in smaller infants, we reviewed the course of 18 infants aged 6 months or less who underwent this procedure. The mortality rate in 4 infants under 2 weeks of age was 50 per cent and that in those 2 weeks to 6 months of age, 28 per cent. The patency rate was 70 per cent. Because of late problems with the Waterston shunt and a comparable mortality rate, the Blalock-Taussig procedure is recommended for all infants, except perhaps those under 2 weeks of age.

Afterload reduction with hydralazine following valve replacement.

Impedance reduction with hydralazine was evaluated in 23 patients 1 to 3 hours after aortic or mitral valve replacement. Patients were randomly assigned to Group 1 (0.25 mg/kg) or Group 2 (0.5 mg/kg) and responses at 20, 60, and 120 minutes compared with control (paired t test) and mean values for each group compared (t test). In Group 1 significant responses were the fall in mean arterial pressure (78.3 +/- 3.0 to 66.7 +/- 2.2 mm Hg) and systemic vascular resistance (2,808 +/- 264 to 1,823 +/- 164 dynes-sec/cm5); the increase in cardiac index (2.07 +/- 0.13 to 2.71 +/- 0.21 L/min/m2), stroke volume index (26.9 +/- 2.3 to 34.0 +/- 3.3 ml/beat), and heart rate (80.8 +/- 5.8 to 84.2 +/- 6.6 beats/min). Central venous pressure did not change and left atrial pressure decreased at 120 minutes. Group 2 responses were similar except for higher central venous pressure at 20 minutes, higher left atrial pressures at control, 20, and 60 minutes, and lower left ventricular stroke work at control, 20, and 60 minutes. By selectively dilating the arterial system, hydralazine reduces mean arterial pressure and systemic vascular resistance and increases cardiac output with suble filling pressures.

Pathologic bronchial vasculature in a case of massive hemoptysis due to chronic bronchitis.

The cause of bleeding in a patient with recurrent massive hemoptysis was not apparent after bronchoscopy and gross examination of the lobectomy specimen. Histologic submission of all major bronchi uncovered dilated, tortuous bronchial arteries just below the bronchial mucosa with sites of both current and healing arterial rupture. This bronchial arterial abnormality is common to several chronic pulmonary diseases, but is rarely diagnosed as a cause of massive hemoptysis. Careful pathologic examination of major bronchi in the setting of hemoptysis of unknown causation is recommended.

Operative flow measurements and coronary bypass graft patency.

Early (one week) and late (one year) postoperative angiography was performed in 142 patients having 310 grafts (117 right coronary artery [RCA], 134 left anterior descending [LAD], and 59 circumflex coronary artery [CCA]) to assess the factors responsible for failure of aorta-coronary artery saphenous vein grafts. Early catheterization revealed an 85.5 per cent patency rate with similar rates for each artery (RCA 88 per cent, LAD 85 per cent, and CCA 81 per cent). At one year 238 grafts remained patent, for a cumulative patency rate of 76.8 per cent with a similar distribution for each vessel (RCA 75 per cent, LAD 78 per cent, and CCA 76 per cent). Intraoperative flow measurements were correlated with early and late patency. Grafts with a basal flow less than 20 ml. per minute have a 42 per cent early closure rate and a 21 per cent late closure rate (cumulative 63 per cent). A basal flow of less than 40 ml. per minute was associated with a 25 per cent early failure and an 11 per cent late failure rate (cumulative 36 per cent). Basal flow at levels greater than 40 ml. per minute was not associated with an increased probability of graft closure. Absence of reactive hyperemia (30 second graft occlusion) was associated with a 19 per cent probability of early closure and a 31 per cent probability of cumulative thrombosis. A papaverine-induced flow increase (15 mg. given into the graft) of less than 100 per cent over basal flow gave a 20 per cent probability of early failure and 30 per cent probability of cumulative closure. Thus intraoperative basal flow measurements are of predictive value in determining the fate of aorta-coronary artery vein bypass grafts, and vasodilatory maneuvers provide little additional information.

Intraoperative autotransfusion in cardiac operations. Effect on intraoperative and postoperative transfusion requirements.

The Southern Arizona Regional Red Cross Blood Program, in cooperation with two cardiac surgery groups, examined the effect of intraoperative autotransfusion on red cell, plasma, and platelet usage during and after cardiac operations. The study evaluated whether intraoperative autotransfusion influenced intraoperative or postoperative blood usage and whether regular use was more effective than selective use. The study demonstrated that intraoperative autotransfusion reduces intraoperative and postoperative blood use and that regular use of intraoperative autotransfusion is more effective than selective use.

Left ventricular aneurysmectomy.

Comparison of preoperative and postoperative studies in 81 patients undergoing left ventricular aneurysmectomy failed to show consistent hemodynamic trends. The most reliable prognostic indicator for survival (84% early, 71% late) was the function of the basilar ventricular segments. In 62 of the 81 patients, there was concomitant aortocoronary bypass grafting. Eighty-eight percent of the surviving patients are essentially free of symptoms. These findings support the continued surgical treatment of ventricular aneurysm in symptomatic patients, and suggest nonoperative treatment for patients who are asymptomatic.

Implantable pacemakers in children.

Permanent pacemakers were implanted in 12 children, ages 2 weeks to 6 years. The cause of the arrhythmia was congenital in three, postoperative in six, viral in one, and unknown in two. One operative death occurred on the second postoperative day. Two late deaths occurred five and 10-1/2 years postoperatively. The late deaths were in patients with good cardiac capture in whom the block followed repair of tetralogy of Fallot. Ventricular arrhythmias were believed to be the cause of death. Reoperation was required 37 times: for pacemaker exhaustion, 17; electrode problems, 15; wound problems, four; and arrhythmia, one. Nine of 12 patients are alive nine months to ten years eight months postoperatively. The remaining three survived for eight to ten years. Frequent reoperation and dilligent correction of defective pacing is rewarded with long, active lives in children requiring implantable pacemakers.

Topical cardiac hypothermia and phrenic nerve injury.

The relationship between ice-chip cardioplegia and impaired left diaphragmatic function was evaluated in dogs. Direct or indirect contact of the phrenic nerve with crushed ice for 30 or 60 minutes resulted in phrenic paralysis for 6 to 28 days, with responsiveness returning from 7 to 62 days later. Microscopical examination of injured nerves revealed injury to the myelin sheath and preservation of axons. Paralysis of the left diaphragm after topical cardiac hypothermia may be secondary to cold injury of the phrenic nerve, which is reversible.

In favor of the Y-graft for aortocoronary bypass.

The technique of multiple coronary artery bypass grafting has included separate conduits, snake grafts, and Y-grafts. Against the Y-graft have been reports of lesser patency and several theoretical objections. The theory is discussed and a laboratory model presented which demonstrates a flow difference of 2 ml/5 sec or less between Y-grafts and single grafts. In conjunction with this, 171 patients having aortocoronary bypass were analyzed and showed a combined one-year graft patency of 77% with no significant difference between single grafts and Y-grafts. It is concluded that the technical simplicity of Y-grafts is advantageous and that, if the operation is performed within the guidelines set forth, revascularization with Y-grafts is an acceptable method.

Coronary venous arterialization: acute hemodynamic, metabolic, and chronic anatomical observations.

Nine dogs that had anastomosis of the internal mammary artery (IMA) to the left anterior descending coronary vein (LADV) were studied acutely on right-heart bypass. Occlusion of the left anterior descending coronary artery (LADA) and LADV without venous arterialization resulted in a significant decline in stroke work, total coronary flow, and myocardial oxygen uptake; with reactive hyperemia an increase in lactate and pyruvate consumption resulted. Occlusion of the LADA and LADV with VA did not change these variables greatly, except for a marked increase in total coronary flow with reactive hyperemia. Chronic venous arterialization in 14 dogs was associated with a 14% mortality, while 10 controls had a 40% mortality. Dogs were killed at six weeks, and prior angiography in 9 showed patency of the IMA to the heart without filling of cardiac veins. All dogs had infarcts in the distribution of the LADA; these infarcts were smaller in dogs with venous arterialization. The anastomoses were obliterated by mature or maturing fibrous tissue, with alteration of the vein so that it was frequently not discernible, while the IMA was well preserved. Distal veins had foci of intimal proliferation, subintimal fibrosis, and medial hypertrophy. Although venous arterialzaiton provides protection for the acutely ischemic myocardium, this effect does not persist, perhaps because of anastomotic occlusion due to fibrous proliferation.

A servocontrolled atrial-aortic assist device: experimental findings and clinical experience.

A servocontrol system was developed to regulate a single roller pump left atrial-aortic (La-A) assist device. Responsiveness of the servomechanism to blood volume changes, myocardial damage, and mitral regurgitation was evaluated in 5 sheep and 6 dogs. Myocardial damage was induced by occlusion of coronary arteries. and the hemodynamic effects of La-A assistance were evaluated. While La-A assistance reduced left atrial pressures to low levels, the left ventricular end-diastolic pressure remained elevated in the severely damaged heart. LaA-assistance was used in 3 patients. Two were weaned from cardiopulmonary bypass after failure of intraaortic balloon counterpulsation, and 1 is a long-term survivor. The third was supported for 48 hours after attempt repair of complex congenital heart disease. The servocontrol device added to the safety of prolonged La-A assistance. This mode of assistance should be considered when intraaortic balloon counterpulsation has failed.

Intraaortic balloon assistance.

Intraaortic balloon (IAB) assistance in 64 patients over 2 1/2 years has resulted in a survival rate of 11% (1 patient) when used alone but 47% when utilized in patients treated surgically (long-term survival, 38% [21 patients]). Patients undergoing coronary artery bypass grafting or aortic valve replacement have a long-term survival of 50% (8 and 9 patients, respectively). The required duration of IAB support has a bearing on the clinical result. Complications have been minimal. Though it was originally developed to assist in the nonoperative management of complications of ischemic heart disease, IAB assistance offers significant promise as an adjuvant to operative therapy for both ischemic and valvular heart disease.