ß-D-glucosidase assisted gold dissolution as non-optical and quantifiable detection technique for immunoassays.

Immunoassays are used for detecting protein targets for various applications. Here, a modification of immunoassays to allow a purely electrical detection of the target protein concentration is shown. The modification comprises a ß-D-glucosidase as reporter enzyme and a cyanogenic glycoside as substrate. The enzymatic reaction produces cyanide in small quantities. For electrical detection of the cyanide, a novel sensor is developed, based on a gold micro wire. The cyanide dissolves the gold wire and changes the electrical resistance of the wire. Monitoring the resistance change allows a quantitative measurement of the target human C-reactive protein (an inflammatory marker) in blood plasma in the physiological relevant concentration range.

Can we accept donors who have suffered a resuscitated cardiac arrest?

INTRODUCTION AND AIMS: The shortage of donor organs has prompted increased acceptance of hearts from donors with more comorbidities. With increasing frequency, hearts are being offered from patients who have undergone a resuscitated cardiac arrest (RCA). Our aim was to compare the rate of complications in the postoperative and follow-up periods, depending on whether the transplanted organ came from a donor who had undergone an RCA. MATERIALS AND METHODS: We included all 604 heart transplantations (HTs) performed in our center from 1987 to 2009, including 25 recipients who received an organ from a donor who had undergone RCA. We considered RCA to be an in-hospital cardiac arrest that was resuscitated from the onset, with a duration of <30 minutes, and with total recovery of cardiac and hemodynamic function. We analyzed ischemia time, incidence of acute graft failure (AGF), intubation period, recovery room stay, and long-term survival. The statistical methods were Student t and chi-square tests. RESULTS: There were no differences in baseline characteristics, except that patients in the RCA group were younger (47±13 vs 51±11 years; P=.50). There were also no differences between the RCA group and the other patients in ischemia time (151±50 vs 154±53 minutes; P=.826), incidence of AGF (33% vs 24.7%; P=.311), hours of intubation (76±204 vs 72±249; P=.926), days of recovery room stay (6±7 vs 8±6; P=.453), or survival after HT (53±54 vs 53±52 months; P=.982). CONCLUSIONS: Patients receiving a heart from a patient with an in-hospital RCA and subsequent hemodynamic stability have a similar outcomes to other HT patients.

Clinical predictors of immunotolerance in heart transplantation.

BACKGROUND AND AIM: The drugs routinely administered to prevent rejection often cause lethal side effects. Tolerant patients, therefore, should be identified to minimize these problems. The aim of this analysis was to identify clinical variables that may be associated with tolerance. METHODS: We recruited 522 heart transplants (HT), excluding combined procedures, retransplantations, pediatric recipients, and subjects who died in the first year to obtain a cohort of 375 patients. Two groups were distinguished by the presence of echocardiographic, clinical, or pathological evidence of rejection in the first year (15 echocardiograms and 10 protocol biopsies per patient); 99 tolerant patients were compared with 276 nontolerant patients. We analyzed clinical variables related to morbidity and mortality. RESULTS: The univariate analysis showed few differences between the groups. The multivariate analysis showed that only major histocompatibility complex (MHC)-A and MHC-DR matched recipients were significantly associated with tolerance. Thus, the likelihood of tolerance was increased by 1.7- and 2.8-fold if 1 or 2 MHC-I matches were present and by 3.4- and 3.7-fold if 1 or 2 MHC-DR matches were present, respectively survival curves showed significant differences (P=.034). Most deaths in both groups were related to immunosuppressive drugs; among tolerant subjects, deaths were due to infection and neoplasms and among nontolerant patients, deaths were due to chronic rejection, neoplasms, and infection. CONCLUSIONS: The only clinical parameter that can determined whether a HT recipient was tolerant was MHC-A and MHC-DR matching. If there is matching, a reduced immunosuppressive load should be prescribed to prevent drug toxicity.

Normalization of the heart rate response to exercise 6 months after cardiac transplantation.

INTRODUCTION: Heart transplant recipients show an abnormal heart rate (HR) response to exercise due to complete cardiac denervation after surgery. They present elevated resting HR, minimal increase in HR during exercise, with maximal HR reached during the recovery period. The objective of this study was to study the frequency of normalization of the abnormal HR in the first 6 months after transplantation. MATERIALS AND METHODS: We prospectively studied 27 heart transplant recipients who underwent treadmill exercise tests at 2 and 6 months after heart transplantation (HT). HR responses to exercise were classified as normal or abnormal, depending on achieving all of the following criteria: (1) increased HR for each minute of exercise, (2) highest HR at the peak exercise intensity, and (3) decreased HR for each minute of the recovery period. The HR response at 2 months was compared with the results at 6 months post-HT. RESULTS: At 2 months post-HT, 96.3% of the patients showed abnormal HR responses to exercise. Four months later, 11 patients (40.7%) had normalized HR responses (P<.001), which also involved a significant decrease in the time to achieve the highest HR after exercise (124.4±63.8 seconds in the first test and 55.6±44.6 seconds in the second). A significant improvement in exercise capacity and chronotropic competence was also shown in tests performed at 6 months after surgery. CONCLUSIONS: We observed important improvements in HR responses to exercise at 6 months after HT, which may represent early functional cardiac reinnervation.

Mortality from renal dysfunction in heart transplant patients: creatinine versus glomerular filtration rate.

INTRODUCTION: One of the most common, significant problems after heart transplantation (HT) is the development of renal dysfunction. In recent years, the glomerular filtration rate (GFR) has replaced the serum creatinine as the standard parameter for its determination. Our objective was to analyze which renal function parameter (creatinine or GFR) at 1 year after HT better classified patients who will die during follow-up. PATIENTS AND METHODS: The study included 316 consecutive HT patients surviving at least 1 year after transplantation. Creatinine and GFR were determined by the Modification of Diet in Renal Disease Study (MDRD4) equation. Mortality during the follow-up was analyzed to compare both parameters using receiver operating characteristic curves. RESULTS: Over a mean follow-up of 6±3 years, 97 patients died (30.7%). At 1 year after HT, the patients who succumbed displayed a significantly higher mean creatinine value (1.63±0.65 vs 1.41±0.64 mg/dL; P=.004) and a more decreased GFR (53.8 vs 60.8 mL/min/1.73 m2; P=.006). Both groups had the same area under the curve, 0.61 (95% confidence interval: 0.54-0.68; P=.002). CONCLUSION: Among our population, GFR calculated by the abbreviated MDRD4 equation did not provide any additional prognostic value to serum creatinine at 1 year after HT to predict long-term mortality.

Post-heart transplant tumors: chronology and impact on survival.

INTRODUCTION AND AIMS: Tumors are the second leading cause of death beyond the first year heart transplantation (HT). The aim of our study was to establish a chronology for the occurrence and the impact on overall survival of de novo neoplasms after HT. MATERIALS AND METHODS: We included 597 patients undergoing HT from January 1987 to December 2008. De novo tumors were classified into groups: Kaposi's sarcoma, melanoma, epidermoid skin carcinoma, other skin tumors, lung neoplasms, bladder tumors, prostate adenocarcinoma, digestive tumors, lymphomas, and other tumors. We based the study on the median value and interquartile range of the tumors to estimate their occurrence. Survival rates were calculated using Kaplan-Meier curves and the log-rank tests. We included only patients with survivals beyond 1 year after HT. RESULTS: A total of 109 tumors developed during the follow-up. There were no differences in the survival of patients who lived more than 1 year regarding the development or not of a tumor (155±8 vs 179±6 months; P=.177). CONCLUSIONS: The incidence of tumor occurrence after HT was high (18.25%). There were several periods in which the occurrence of certain tumors was more frequent, while other periods appeared to be tumor-free. As most tumors were skin cancers, their impact on overall survival was low.

Preliminary results of a prospective randomized study of cyclosporine versus tacrolimus in the development of cardiac allograft vasculopathy at 1 year after heart transplantation.

INTRODUCTION AND AIMS: Cardiac allograft vasculopathy (CAV) is the leading cause of death after the first year post-heart transplantation (HT). Numerous factors have been implicated in the development of CAV. The aim of this prospective randomized study was to assess the impact of cyclosporine (CsA) and tacrolimus (Tac) on the development of CAV. MATERIALS AND METHODS: From November 2006 to October 2008, 49 HT patients in our center were randomized to receive CsA or Tac. The additional treatment for all patients consisted of daclizumab induction and maintenance treatment with mycophenolate mofetil (1 g/12 hours) and steroids (withdrawal was not attempted). Thirteen patients died before coronary arteriography plus intravascular ultrasound of the left anterior descending artery was performed at 1 year after HT. Hence, the final number of patients included was 36 (18 per group). We considered significant CAV to be the presence of intimal proliferation>1 mm and/or>0.5 mm in 180°. The statistical methods were Student t and chi-square tests. RESULTS: There were no differences in baseline characteristics between the two groups. Nor were there significant differences in maximum intimal proliferation between the groups (CsA 0.65±0.29 vs Tac 0.82±0.51 mm; P=.292) or in the development of significant CAV when both criteria were combined (CsA 31.6% vs Tac 38.9%; P=.642). CONCLUSIONS: One year after HT, no differences were detected in the development of significant CAV according to the type of calcineurin inhibitor used when combined with daclizumab induction and maintenance treatment with mycophenolate mofetil and steroids.

Lymphomas in heart transplant recipients: do antivirals protect against the neoplastic effect of anti-CD3 monoclonal antibody?

INTRODUCTION AND AIM: After cardiac allograft vasculopathy, tumors are the second leading cause of death among heart transplantation (HT) patients after the first year. Lymphomas are tumors of lymphocytic origin whose development has been associated with the use of anti-CD3 monoclonal antibody (OKT3). Some studies suggest that the use of acyclovir could counteract this effect. Our aim was to investigate the impact of gancyclovir on OKT3 and lymphoma development after HT. MATERIALS AND METHODS: We included all 239 HTs performed in our center from 1989 to 2002. We divided patients into those who received gancyclovir treatment (prophylaxis, pre-emptive therapy, or for cytomegalovirus infection) versus those who did not receive this agent at any time during follow-up (88 vs 151 patients). The statistical methods were Student's t and chi-square tests. RESULTS: There were no differences in the baseline characteristics of the patients--gender, recipient age, etiology leading to HT, diabetes, and dyslipidemia--except for a higher rate of hypertension among the group who did not receive gancyclovir (73.7 vs 60.2%; P=.03). None of the 7 patients who developed lymphomas during the follow-up received gancyclovir (0 vs 4.6%; P=.040). CONCLUSIONS: Antivirals may have a relevant role to neutralize potential neoplastic effects (especially lymphomas) associated with the use of OKT3 induction therapy.

Infección por Nocardia en pacientes trasplantados cardiacos / Nocardia infection in heart transplant recipients

Introducción. La incidencia de la infección por Nocardia en pacientes trasplantados oscila entre el 0,7–3% y conlleva una mortalidad elevada (26–63%). Este artículo pretende precisar las características epidemiológicas, clínicas y evolutivas de los pacientes con transplante cardiaco que desarrollan nocardiosis en nuestro medio. Métodos. Cohorte retrospectiva de 570 pacientes trasplantados cardiacos. Se revisan las historias clínicas de aquellos en los que se realizó el diagnóstico de infección por Nocardia durante el seguimiento y se registraron datos demográficos, antecedentes personales, régimen de inmunosupresión, profilaxis antibiótica, episodios de rechazo, infecciones asociadas, así como, lugar de la infección por Nocardia, tratamiento administrado y evolución. Resultados. Se identificaron 4 casos con nocardiosis (incidencia del 0,73%), siendo en 2 de ellos diseminada. En todos hubo afectación pulmonar. La mortalidad fue elevada (2 de los 4 pacientes). Conclusión. En pacientes trasplantados cardiacos la infección por Nocardia es poco frecuente y conlleva una elevada mortalidad. Sería necesario un diagnostico precoz para instaurar un tratamiento adecuado(AU)

Introduction. The incidence of Nocardia infection in transplant patients ranges between 0.7 and 3% with a high mortality (26–63%). This fact, together with a median time to diagnosis in about two weeks ago that the state of alertness is of vital clinical importance. Methods. From a cohort of 570 cardiac transplant patients, we reviewed the medical records of those who underwent the diagnosis of Nocardia infection during follow-up. Results. We identified four cases (incidence 0.73%), two scattered. In all, had pulmonary involvement. Mortality was high (2 of 4 patients). Conclusion. In cardiac transplant patients Nocardia infection is rare but has a high mortality, being necessary an early diagnosis to establish an appropriate treatment(AU)

[Nocardia infection in heart transplant recipients]. / Infección por Nocardia en pacientes trasplantados cardiacos.

INTRODUCTION: The incidence of Nocardia infection in transplant patients ranges between 0.7 and 3% with a high mortality (26-63%). This fact, together with a median time to diagnosis in about two weeks ago that the state of alertness is of vital clinical importance. METHODS: From a cohort of 570 cardiac transplant patients, we reviewed the medical records of those who underwent the diagnosis of Nocardia infection during follow-up. RESULTS: We identified four cases (incidence 0.73%), two scattered. In all, had pulmonary involvement. Mortality was high (2 of 4 patients). CONCLUSION: In cardiac transplant patients Nocardia infection is rare but has a high mortality, being necessary an early diagnosis to establish an appropriate treatment.

Exercise tolerance after beta blockade in recent cardiac transplant recipients.

OBJECTIVE: Exercise capacity has been shown to be reduced among cardiac transplant recipients. This observation is directly connected to both the transplanted heart's dependence on circulating catecholamines and the abnormal sympathoadrenal response to exercise in these patients. Taking into account this background, there is reluctance to use beta-blockers after heart transplantation. Nevertheless, this point remains controversial. Our aim was to examine exercise tolerance after an oral dose of atenolol early after cardiac transplantation. MATERIALS AND METHODS: Eighteen nonrejecting, otherwise health, cardiac transplant recipients were included in this study at a mean of 61.9 +/- 25.6 days after surgery; 13 were men. Patients performed controlled exercise to a symptom-limited maximum before and 2 hours after taking an oral dose of atenolol. Heart rate, blood pressure, exercise time, and metabolic equivalent units (METS) were recorded at rest as well as during and after exercise. We compared results depending on taking atenolol. RESULTS: Resting (101.7 +/- 14.5 vs 84 +/- 12.4 bpm; P = .001) and peak heart rates (128.5 +/- 12.9 vs 100.7 +/- 16 bpm; P = .001) were significantly higher before than after beta blockade. Resting systolic blood pressure was slightly higher before compared with after beta blockade (129.3 +/- 23.6 vs 122.2 +/- 20.3 mm Hg; P = .103). However, there was neither a significant difference in the length of exercise (3.17 +/- 1.96 vs 3.40 +/- 2.48 minutes; P = .918) nor in the estimated oxygen consumption (METS; 5.07 +/- 1.8 vs 5.31 +/- 2.2; P = .229). Furthermore, no patient reported a greater degree of tiredness after beta blockade. CONCLUSIONS: This study showed little adverse effect on exercise tolerance by beta blockade in recently transplanted patients. Atenolol seemed to be safe in this context.

Randomized prospective study of the evolution of renal function depending on the anticalcineurin used.

BACKGROUND: Renal failure is one of the primary medium- to long-term morbidities in heart transplant (HT) recipients. To a great extent, this renal deterioration is associated with calcineurin inhibitors, primarily cyclosporine A (CsA). It has been suggested that tacrolimus provides better renal function in these patients. We assessed the medium-term evolution of renal function depending on the calcineurin inhibitor used after HT. PATIENTS AND METHOD: We assessed 40 consecutive HT recipients over one year. Patients were randomized to receive CsA (n = 20) or tacrolimus (n = 20) in combination with mycophenolate mofetil (1 g/12 h) and deflazacort in decreasing dosages. We analyzed demographic variables before HT, creatinine values before and six months after HT and incidence of acute rejection. RESULTS: No demographic, clinical, or analytical differences were observed were between the two groups before HT. Repeated measures analysis of variance of creatinine values showed no significant differences between the two groups (P = .98). Furthermore, no differences were observed in either the incidence of rejection (P = .02) or rejection-free survival (P = .14). CONCLUSION: There seems to be no difference in efficacy profile and renal tolerability between CsA and tacrolimus therapy during the first months after HT.

Clinical variables associated with the presence of inflammatory infiltrates in patients with dilated cardiomyopathy undergoing heart transplantation.

INTRODUCTION: Idiopathic dilated cardiomyopathy (DCM) is, together with ischemic heart disease, the major cause of end-stage heart failure leading to heart transplantation. However, an unknown percentage of patients with this diagnosis has inflammatory foci found in the histopathological study of the explanted heart. This fact suggests an undetected process of acute myocarditis as the cause of cardiac dysfunction. OBJECTIVE: The objective of this study was to identify clinical and echocardiographic variables related to the presence of myocardial infiltrates, as a potential guide to determine which patients should undergo endomyocardial biopsy in DCM. MATERIALS AND METHODS: We retrospectively analyzed 161 patients who underwent heart transplantation with a diagnosis of DCM between 1987 and 2007. The presence of inflammatory infiltrates was considered significant when the histopathological study of tissue blocks from the left ventricle showed 1 or more foci per cm(2) of perivascular or interstitial mononuclear or polymorphonuclear cells, whether or not in the presence of cytolysis. RESULTS: Seventeen patients (11%) had these inflammatory histological findings; of them, 6 (35%) showed preponderance of eosinophils and 7 (41%) showed areas of cytolysis. The DCM group with inflammatory infiltrates showed significant differences in terms of younger age (45 +/- 15 vs 50 +/- 11 years; P < .01) and smaller ventricular diameters (P < .05). Male gender was more frequent in this group, and the patients had a poorer clinical status and greater dependence on inotropic drugs. CONCLUSIONS: Inflammatory infiltrates are frequently present in DCM explanted hearts. Although there are no relevant clinical variables to identify subclinical myocarditis, these patients are younger and have smaller ventricular diameters and poorer functional status at the time of transplantation.

Effect of hypertension, diabetes, and smoking on development of renal dysfunction after heart transplantation.

BACKGROUND: Renal dysfunction is a serious problem after heart transplantation (HT). The objective of this study was to determine the cardiovascular risk factors associated with medium- to long-term dysfunction after HT. MATERIALS AND METHODS: We studied 247 consecutive patients who underwent HT between January 2000 and September 2006 who survived for at least 6 months. We excluded patients receiving combination transplants, those undergoing repeat HT, and pediatric patients undergoing HT. Mean (SD) follow-up was 72 (42) months. We defined renal dysfunction as serum creatinine concentration greater than 1.4 mg/dL during follow-up. Patients were considered to be smokers if they had smoked during the six months before HT, to have hypertension if they required drugs for blood pressure control, and to have diabetes if they required insulin therapy. Statistical tests included the t test and the chi(2) tests. We performed Cox regression analysis using significant or nearly significant values in the univariate analysis. RESULTS: Mean (SD) age of the patients who underwent HT was 52 (10) years, and 217 (87.9%) were men. Renal dysfunction was detected during follow-up in 135 (54.5%) patients. The significant variables at univariate analysis were smoking (61.4% vs. 43.2%; P = .01) and previous renal dysfunction (94.1% vs 52.7%; P = .001). Nearly significant variables were the presence of hypertension before HT (63.8% vs 51.1%; P = .09) and after HT (58.2% vs 44.8%; P = .082). At multivariate analysis, pre-HT smoking and previous renal dysfunction were significant correlates (P = .04 and P = .01, respectively). CONCLUSIONS: Renal dysfunction is common after HT. In our analysis, the best predictors were pre-HT dysfunction and smoking. Less important factors were advanced age and post-HT hypertension.

Undetected burden of tuberculosis in a low-prevalence area.

SETTING: Under-ascertainment and under-reporting of tuberculosis (TB) hampers surveillance and control. Case detection is improved by record linkage of case registers and under-reporting can be estimated by capture-recapture (CR) analysis. OBJECTIVES: To assess the completeness of the TB registration systems and estimation of TB incidence and under-reporting in the Piedmont Region of Italy in 2001. METHODS: Record linkage of the 'physician notification system', the TB laboratory register and the hospital records register, and subsequent three-sample CR analysis. RESULTS: Record linkage identified 657 TB cases; CR analysis estimated 47 (95%CI 31-71) unrecorded cases. Under-reporting of the 'physician notification system' was estimated at 21% (95%CI 20-23). The overall estimated TB incidence rate was 16.7 cases per 100000 population (95%CI 16.3-17.3), varying according to the subset investigated: 12.7 for individuals from low TB prevalence countries and 214.1 for immigrants from high TB prevalence countries; 13.1 and 25.8 for persons aged < and > or = 60 years, respectively; and 32.1 in Turin, the regional capital and 10.8 in the rest of the region. CONCLUSIONS: When multiple recording systems are available, record linkage and CR analysis can be used to assess TB incidence and the completeness of different registers, contributing to a more accurate surveillance of local TB epidemiology.

Cardio 7--portable system for high resolution ECG mapping.

One of the main difficulties in using body surface potential mapping (BSPM) techniques is the need of complicated multi-channel measuring system. In this paper practical portable ECG mapping system is introduced. The system consists of a notebook computer and a data acquisition system box connected to the computer by fast IEEE 1284 parallel interface working in ECP mode. Concept of the device enables to extend the basic 134-channel high-resolution multi-channel ECG amplifying unit up to 256 channels. Application software includes measurement and real time monitoring of ECG signals, computation and display of several types of body surface potential maps. System can be connected to hospital information networks and supply them with measured ECG data for advanced processing or central archiving.

Open access atmospheric pressure chemical ionization Mass spectrometry for routine sample analysis.

We report the introduction and use of an atmospheric pressure chemical ionization liquid chromatography-mass spectrometry instrument that has been designed specifically for use by the synthetic chemist on an open access, walk-in basis. This instrument has been configured with an easy-to-use sample log-in terminal that requires the user to provide only a sample identification number and a user name. Sample analysis takes approximately 4 min and provides the synthetic and medicinal chemist with rapid and reliable mass spectrometry analysis. Since installation of the system, it has analyzed an average of about 80 samples per day and has the capacity to run over 100 samples per day without the intervention of a specialist operator. This capability has eliminated the need for an operator to analyze routine samples and allows the mass spectroscopist more time to deal with problem solving.