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.

Long-term risk of vascular events after peripheral bypass surgery. A cohort study.

Patients with peripheral arterial disease (PAD) are at high risk of major ischaemic events. Long-term data of all major ischaemic events in PAD patients are scarce and outdated, especially for patients with severe PAD requiring bypass surgery. Our objective was to define their long-term prognosis and develop a prediction model which quantifies this risk up to a decade after surgery. We conducted a retrospective cohort study in patients from the Dutch Bypass Oral anticoagulants or Aspirin (BOA) Study; a multicentre randomised trial comparing oral anticoagulants with aspirin after infrainguinal bypass surgery. The primary outcome was the composite event of non-fatal myocardial infarction, non-fatal ischaemic stroke, major amputation, and vascular death. Cumulative risks were assessed by Kaplan-Meier analysis and independent determinants by multivariable Cox regression models. From 1995 until 2009, 482 patients were followed for a median period of 7.8 years. Follow-up was complete in 94%. Overall 60% of patients experienced a primary outcome event, of which the majority was a vascular death (30%), followed by major amputations (12%). The primary cause of vascular death was a cardiovascular event (29%), whereas the minority was due to complications directly related to PAD (6%). Within five years after bypass surgery vascular death occurred in about a quarter of patients and within 10 years in nearly half of patients. This was double the rate as for non-vascular death. The primary outcome event occurred in over a third and over half of patients in 5 and 10 years after bypass surgery, respectively. From four independent determinants for the primary outcome event: age, diabetes, critical limb ischaemia, and prior vascular interventions, we developed a risk chart, which systematically classifies the 10-year risks of the primary outcome event, ranging from 25% to 85%. This study provided a detailed insight in the course of PAD long after peripheral bypass surgery and enables individual risk assessment of major fatal and non-fatal ischaemic events by means of cumulative incidences and a risk chart.

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.

Growth predictors and prognosis of small abdominal aortic aneurysms.

OBJECTIVE: Evidence regarding the influence of cardiovascular risk factors, comorbidities, and patient characteristics on the growth of small abdominal aortic aneurysms (AAA) is limited. We assessed, in an observational cohort study, rupture rates, risks of mortality, and the effects of cardiovascular risk factors and patient demographics on growth rates of small AAAs. METHODS: Between September 1996 and January 2005, 5057 patients with manifest arterial vascular disease or cardiovascular risk factors were included in the Second Manifestation of ARTerial disease (SMART) study. Measurements of the abdominal aortic diameter were performed in all patients. All patients with an initial AAA diameter between 30 and 55 mm were selected for this study. All AAA measurements during follow-up until August 2007 were collected. Multivariate regression analysis was performed to calculate the effects of demographic patient characteristics, initial AAA diameter, and cardiovascular risk factors on AAA growth. RESULTS: Included were 230 patients, with a mean age of 66 years and 90% were male. Seven AAA ruptures (six fatal) occurred in 755 patient years of follow-up (rupture rate 0.9% per patient-year). In 147 patients, AAA measurements were performed for a period of more than 6 months. The median follow-up time was 3.3 years (mean 4.0, range 0.5 to 11.1 years, standard deviation (SD) 2.5). Mean AAA diameter was 38.8 mm (SD 6.8) and mean expansion rate 2.5 mm/y. Patients using lipid-lowering drugs had a 1.2 mm/y (95% confidence interval [CI] -2.34 to -0.060 mm/y) lower AAA growth rate compared to nonusers of these drugs. Initial AAA diameter was associated with a 0.09 mm/y (95% CI 0.01 to 0.18 mm/y) higher growth rate per millimetre increase of the diameter. No other factors, including blood lipid values, were independently associated with AAA growth. CONCLUSIONS: Lipid-lowering drug treatment and initial AAA diameter appear to be independently associated with lower AAA growth rates. The risk of rupture of these small abdominal aortic aneurysms was low, which pleads for watchful waiting.

The rate of NSAID-induced endoscopic ulcers increases linearly but not exponentially with age: a pooled analysis of 12 randomised trials.

The risk of major ulcer complications on treatment with non-steroidal anti-inflammatory drugs (NSAIDs) is known to increase exponentially with age. However, in a pooled analysis of 12 trial arms, the incidence of endoscopic ulcers on treatment with NSAID was found to increase with age in a roughly linear fashion. Thus, it is concluded that increasing age is associated with both more frequent and more serious NSAID gastropathy.

Canine infection and the possible role of dogs in the transmission of American tegumentary leishmaniosis in Salta, Argentina.

Some Leishmania species affect humans in two principal forms: visceral and cutaneous leishmaniosis (CL). Several studies have identified dogs as the main reservoirs of the visceral leishmaniosis (VL) caused by Leishmania infantum. The purpose of this work was to carry out a survey of the canine population associated with human cases of American tegumentary leishmaniosis (ATL), in order to establish the clinical, parasitological, serological and immunological characteristics of the canine disease, in an endemic region for both ATL and Chagas' disease in the province of Salta, in northwestern Argentina. Two hundred and eight dogs from the endemic area were examined and 41 (19.7%) of them presented lesions compatible with leishmaniosis. In order to investigate the presence of antibodies against Leishmania spp. and Trypanosoma cruzi, sera were screened by ELISA using two complex antigens from these parasites and, because of cross-reactions between them, a specific antigen for diagnosis of T. cruzi infection. Sixty-two (29.8%) of 208 dogs were positive for the complex antigen F45 from Leishmania and 50 (24%) were positive for the complex antigen F105 from T. cruzi. Nine dogs (4.3%) were positive for the specific Ag163B6-cruzipain suggesting that these dogs were truly infected with T. cruzi. Furthermore, three of these nine dogs presented Leishmania sp. in their skin lesions and therefore were considered as infected by both, T. cruzi and Leishmania parasites. The prevalence of Leishmania infection detected by lesions and/or positive serology was 27.4% (57/208). On the basis of previous observations regarding the clustered appearance of human ATL, the dog population was divided into two groups: zone A, dogs living within a 100 m radius from houses with human cases, and zone B, dogs living beyond this limit. The prevalence of ATL in dogs was significantly higher in zone A (34.6%) than in zone B (7.3%), suggesting a strong correlation between canine and human cases. The average time required for a parasitological diagnosis by microscopy was six times longer for dog samples than human ones, and the average number of parasites per 100 microscopic fields was 14-fold lower in canine samples. The high prevalence of Leishmania infection and the close association with human cases, demonstrated that dogs are a very susceptible host for Leishmania infection, but the scarcity of parasites in their lesions suggests that they may not be the main reservoir of the parasite in this endemic area.

Determinants of homologous blood usage utilizing autologous platelet-rich plasma in cardiac operations.

The present study evaluated (1) the influence of the collection of autologous platelet-rich plasma intraoperatively in addition to intraoperative autotransfusion on homologous blood usage and bleeding in cardiac operations; (2) the influence of age, sex, body surface area, type of operation, and reoperations on homologous blood usage and bleeding in cardiac operations utilizing intraoperative autotransfusion and autologous platelet-rich plasma collected intraoperatively; and (3) the influence of the preoperative administration of aspirin, Persantine (dipyridamole), heparin sodium, thrombolytic agents, Coumadin (crystalline warfarin sodium), and nonsteroid, antiinflammatory drugs on homologous blood usage and bleeding in cardiac operations utilizing intraoperative autotransfusion and autologous platelet-rich plasma collected intraoperatively. The results demonstrated a decrease in homologous blood use and bleeding when autologous platelet-rich plasma is collected in addition to the use of intraoperative autotransfusion. All of the patient and procedural variables influenced homologous blood usage and bleeding to some extent. Only the thrombolytic agents affected blood usage by increasing homologous plasma usage. All other drugs evaluated did not influence blood utilization or the amount of bleeding intraoperatively or postoperatively.

Autologous platelet-rich plasma in cardiac surgery: effect on intraoperative and postoperative transfusion requirements.

The Southern Arizona Red Cross Blood program, in conjunction with participating hospitals and cardiac surgeons, evaluated the effect of a program to harvest autologous platelet-rich plasma (PRP) from patients immediately prior to undergoing cardiopulmonary bypass surgery. The PRP was transfused back to the patient after heparin neutralization was achieved at the completion of cardiopulmonary bypass. The effect of this autologous PRP product on homologous plasma and platelet usage was examined. The study demonstrates a significant decrease in homologous plasma and platelet usage when autologous PRP is used in cardiac surgery.

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.

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.

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.

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.

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.

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.

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.