Cellular pathways affected by carbon nanopowder-benzo(α)pyrene complex in human skin fibroblasts identified by proteomics.

One of the crucial and unsolved problems of the airborne carbon nanoparticles is the role played by the adsorbed environmental pollutants on their toxicological effect. Indeed, in the urban areas, the carbon nanoparticles usually adsorb some atmospheric contaminants, whose one of the leading representatives is the benzo(α)pyrene. Herein, we used the proteomics to investigate the alteration of toxicological pathways due to the carbon nanopowder-benzo(α)pyrene complex in comparison with the two contaminants administered alone on human skin-derived fibroblasts (hSDFs) exposed for 8 days in semi-static conditions. The preliminary confocal microscopy observations highlighted that carbon-nanopowder was able to pass through the cell membranes and accumulate into the cytoplasm both when administered alone and with the adsorbed benzo(α)pyrene. Proteomics revealed that the effect of carbon nanopowder-benzo(α)pyrene complex seems to be related to a new toxicological behavior instead of simple additive or synergistic effects. In detail, the cellular pathways modulated by the complex were mainly related to energy shift (glycolysis and pentose phosphate pathway), apoptosis, stress response and cellular trafficking.

Preemptive therapy for systemic and pulmonary human cytomegalovirus infection in lung transplant recipients.

The incidence and treatment of both systemic and pulmonary human cytomegalovirus (HCMV) infection as well as HCMV-specific T-cell immune responses were investigated in 57 consecutive lung transplant recipients (LTR) by using as cutoffs for preemptive therapy: 300 000 DNA copies/mL whole blood for systemic infections and 100 000 DNA copies/mL bronchoalveolar lavage fluid for lung infections. Results showed that out of 29/57 LTR (50.9%) needing preemptive antiviral therapy, 15 (51.7%) reached the blood cutoff, 8 (27.6%) the pulmonary cutoff and 6 (20.7%) both the blood and the lung cutoff (3 simultaneously and 3 subsequently). Recovery of HCMV-specific T-cell immune responses was achieved much earlier for CD8+ than CD4+ T cells. However, protection from HCMV reactivation was conferred by the presence of both arms of the T-cell response. In two LTR reaching the pulmonary cutoff and not preemptively treated, a full HCMV-specific CD4+ and CD8+ T-cell response was associated with resolution of lung infection. Antirejection steroid therapy suppressed T-cell immune responses, thus facilitating HCMV reactivation. In conclusion, in LTR, monitoring HCMV infection in both blood and lungs, may improve preemptive therapy efficacy. In addition, monitoring the HCMV-specific T-cell immune response appears useful for predicting control of HCMV infection in the posttransplant period.

Cardiac transplant vasculopathy treated by percutaneous coronary intervention.

AIM: Cardiac transplant vasculopathy is a limit to long-term survival in heart transplantation (H-Tx) recipients. PTCA results in our H-Tx population were retrospectively analyzed. METHODS: From November 1985 to May 2004, 767 patients underwent heart transplantation. All patients received immunosuppressive therapy with cyclosporine or tacrolimus, azathioprine, steroids and mycophenolate mofetil. Lymphocyte was administrated by 3-7 days course of either rabbit antithymocyte globulins or anti-lymphocyte globulins or by a 14 days course of OKT3. Coronary angiograms were performed every year and more frequently if graft vasculopathy was already diagnosed or suspected. RESULTS: Fifty-two coronary artery lesions were treated during 42 percutaneous transluminal cardioangioplasty (PTCA)/stent procedures in 36 patients. Mean time since heart transplantation to PTCA was 80 +/- 27 months. Indication to PTCA was asymptomatic angiographic graft vasculopathy in 34 patients (94%) and acute myocardial infarction in 2 patients (6%). PTCA was performed on left anterior descending artery in 34 cases (65.4%), on circumflex artery in 10 cases (19.2%), on right coronary artery in 8 cases (15.4%). There were no procedure related deaths. None of the patients required emergency bypass surgery. Two patients had transient acute renal failure. Patient follow-up showed 10 deaths after 1 +/- 54 months from PTCA. Six died for progression of graft vasculopathy, three for cancer and one for gastrointestinal bleeding. Two patients underwent heart retransplantation after 20 and 107 months from the first procedure. Mean follow-up of the remaining patients is 78.3 +/- 50.3 months. CONCLUSION: PTCA may represent a reasonable treatment for graft vasculopathy in selected heart transplant recipients.

Pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension: short-term functional assessment in a longitudinal study.

AIM: Presently, the surgical treatment choice in chronic thromboembolic pulmonary hypertension (CTEPH) consists in a pulmonary endarterectomy (PEA). The aim of the present study is the functional assessment of patients submitted to PEA both preoperatively and shortly after the intervention. A longitudinal study was developed to study the quality and quantity of functional performance possible in these subjects. METHODS: Twenty-two subjects were assessed immediately prior to PEA and 3 months later in order to obtain quantitative measurements of short-term functional recovery. The functional assessment included the 6-min walk test (6mWT), the measurement of the oxygen percent saturation (HbS%O(2)) and the degree of dyspnea subjectively perceived by each patient. RESULTS: Three months after the surgical intervention, there was a definite increase in the number of meters walked during the 6mWT with respect to preintervention; the difference between the distances walked in the 6mWT (6mWD) in the pre and post-PEA was statistically significant (Paired t-test P<0.001). CONCLUSION: In this study the 6mWT resulted to be a useful tool in the functional evaluation of patients affected by CTEPH and submitted to PEA. The average 6mWD significantly improved already at 3 months after the intervention, thus reaching the minimum limit of the range predicted for the healthy control, but remains lower than the average theoretical value predicted (about 75% of the same).

Carbon nanopowder acts as a Trojan-horse for benzo(α)pyrene in Danio rerio embryos.

Carbon-based nanoparticles (CBNs) are largely distributed worldwide due to fossil fuel combustion and their presence in many consumer products. In addition to their proven toxicological effects in several biological models, attention in recent years has focussed on the role played by CBNs as Trojan-horse carriers for adsorbed environmental pollutants. This role has not been conclusively determined to date because CBNs can decrease the bioavailability of contaminants or represent an additional source of intake. Herein, we evaluated the intake, transport and distribution of one of the carbon-based powders, the so-called carbon nanopowder (CNPW), and benzo(α)pyrene, when administered alone and in co-exposure to Danio rerio embryos. Data obtained by means of advanced microscopic techniques illustrated that the "particle-specific" effect induced a modification in the accumulation of benzo(α)pyrene, which is forced to follow the distribution of the physical pollutant instead of its natural bioaccumulation. The combined results from functional proteomics and gene transcription analysis highlighted the different biochemical pathways involved in the action of the two different contaminants administered alone and when bound together. In particular, we observed a clear change in several proteins involved in the homeostatic response to hypoxia only after exposure to the CNPW or co-exposure to the mixture, whereas exposure to benzo(α)pyrene alone mainly modified structural proteins. The entire dataset suggested a Trojan-horse mechanism involved in the biological impacts on Danio rerio embryos especially due to different bioaccumulation pathways and cellular targets.

Multimodal Approach of Pulmonary Artery Intimal Sarcoma: A Single-Institution Experience.

INTRODUCTION: Pulmonary artery sarcoma (PAS) is a rare tumor, whose therapeutic approach is mainly based on surgery, either pneumonectomy or pulmonary endarterectomy (PEA). The prognosis reported in published series is very poor, with survival of 1.5 months without any kind of treatment. PATIENTS AND METHODS: From January 2010 to January 2016, 1027 patients were referred to our hospital for symptoms of acute or chronic pulmonary thromboembolic disease. Twelve patients having a confirmed diagnosis of PAS underwent PEA. Median age was 64.5 years. Most patients had a long history of symptoms, having a median time of 7.5 months from onset of symptoms to surgery. RESULTS: Following PEA and cardiopulmonary rehabilitation, 10 patients received conventional chemotherapy with doxorubicin and ifosfamide, starting at a median of 42 days from surgery. Four patients also received radiotherapy. Four patients have died due to disease progression, while 7 are still alive, with 5 being disease-free at 4-55+ months from diagnosis. CONCLUSIONS: In patients with PAS, a multimodal approach including PEA, CT, and RT is feasible but it should be evaluated individually, according to the tumor extension and the patient's clinical condition. Apart from improving quality of life mainly by reducing or delaying symptoms due to PH, it may improve life expectancy.

Post-traumatic pseudoaneurysm of internal mammary artery: a case report.

Pseudoaneurysm of the internal mammary artery can be a rare complication of surgery, particularly post-sternotomy, or determined by a direct trauma, usually a stab wound. This report presents a pseudoaneurysm by a stab, diagnosed by chest computed tomography scan performed for hemothorax recurrence. The patient underwent left thoracotomy in third intercostal space; mammary vessels were identified above and below the pseudoaneurysm sac and tied. The postoperative course was uneventful.

Comparative proteomic analysis of bronchoalveolar lavage of familial and sporadic cases of idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by progressive deterioration of the alveolar integrity. Among IPF identified phenotypes, that of familial (f-)IPF is usually associated with several gene mutations which are seldom observed in sporadic (s-)IPF. This study aimed at investigating the molecular patterns and variability in f-IPF and s-IPF patients through a differential proteomic analysis. Protein patterns of bronchoalveolar lavage fluid (BALF) samples from 10 familial and 17 sporadic IPF patients were compared using 2D electrophoresis and mass spectrometry. Principal component analysis (PCA) was applied to proteomic data and an enrichment analysis was also performed to characterize specific pathogenic mechanisms and to identify potential biomarkers. BALF samples from f-IPF showed 87 protein spots differentially expressed than those from s-IPF samples; once identified, these spots revealed 22 unique proteins. The functional analysis showed that the endothelial reticulum stress probably plays a central pathogenetic role in f-IPF with an up-regulation of proteins involved in wounding and immune responses, coagulation system, and ion homeostasis. Up-regulated proteins in the s-IPF group were those involved in the oxidative stress response. PCA analysis of differentially expressed proteins clearly distinguished f-IPF from s-IPF patients, and in agreement with radiological and histological patterns, pointed out a higher heterogeneity in f-IPF than s-IPF samples. The 'Slit/Robo signaling', 'clathrin-coated vesicle' and 'cytoskeleton remodelling', were extrapolated by 'pathways analysis' and the results of 'diseases (by biomarkers)' highlighted a 'connective tissue and autoimmune disease', two aspects of increasing interest in IPF.

Recovery of deambulation after cardiothoracic surgery: a single center experience.

BACKGROUND: Surgical procedure and postoperative bed rest lead to musculoskeletal system alterations with a possibility of new walking dependence of patients who undergo cardiothoracic surgery, which is sometimes associated with prolonged hospitalization and increased health expenditure. AIM: The aim of this study was to assess the postoperative motor disability in inpatients admitted to the cardiothoracic surgical ward, and the results of customized rehabilitation in terms of recovery of postural changes and walking capacity with respect to the preoperative condition and destination after discharge. DESIGN: A prospective observational study was conducted. SETTING AND POPULATION: Four hundred seventeen inpatients, who had undergone cardiothoracic surgery, were enrolled between March 2011 and January 2012 in a Hospital Unit of Cardiothoracic Surgery. METHODS: A computerized system was used to collect data about ambulation at home, type and number of rehabilitation sessions proposed, ambulation at discharge, destination after discharge from ward of origin. All patients, who give their consent, undergone rehabilitative treatment on the ward of origin with an expert physiotherapist. RESULTS: Three hundred seventy-five inpatients were examined in Cardiac Surgery. One patient (0.26%) refused rehabilitative treatment. Two patients (0.53%) died. At the time of discharge 236 (74.45%) patients had recovered the ability to walk independently. After discharge 87.64% of patients was transferred to a specialist ward for intensive rehabilitation. Forty-two inpatients were enrolled in thoracic surgery. Two patients died whilst in hospital. At the time of discharge, 36 patients (94.73%) were able to walk independently. After discharge 80% of patients returned home. CONCLUSION: In our study, the application of an early and simple rehabilitation program on the ward of origin after surgery has made possible the recovery of ambulation of most inpatients who referred independence at home in a few days, limiting hospitalization and health expenditure. CLINICAL REHABILITATION IMPACT: Data about recovery of ambulation with respect to the preoperative condition and destination after discharge resume the importance of identifying motor impairment after surgery, in order to apply an adequate, early and feasible rehabilitation protocol to inpatients, limiting hospitalization and health expenditure.

Cadaver lungs for transplantation. Effect of ventilation with alveolar gas.

In an effort to increase the donor pool for lung transplantation (LTX), we have demonstrated the feasibility of LTX from circulation-arrested cadavers in a canine LTX model. We hypothesized that ventilation of the cadaver lung with alveolar gas (20% O2, 5% CO2, balance N2) (AG) would be superior to ventilation with 100% oxygen (O2) after circulatory arrest of the donor. Twelve mongrel dogs were intubated, heparinized and euthanized by pentothal injection and ventilated with AG (n=6) or O2 (n=6). Four hours later, donor animals underwent sternotomy, and the lungs were flushed with cold modified Euro-Collins solution, harvested, and stored inflated in ice slush. Left lung allotransplantation was performed, and recipients were made dependent o n the transplanted lung by occlusion of the contralateral bronchus and pulmonary artery. Recipient animals were ventilated with an FiO2 of 0.4 and followed for 8 hr. Total ischemic time was 7.9 hr for both groups. Pulmonary edema developed in all recipients of AG lungs; one recipient survived the 8-hr observation period with poor oxygenation. In contrast, three of six recipients of O2-ventilated lungs survived for 8-hr with excellent gas exchange. Specimens of donor lungs before and after transplant were evaluated histologically utilizing trypan blue exclusion as an indicator of cell viability. At the time of organ retrieval 4 hr after death, 6% of cells were nonviable in the O2-ventilated cadaver lungs. Circulation-arrested cadaver lungs ventilated with 100% O2 prior to organ retrieval have superior pulmonary function after transplant compared with lungs ventilated with AG. Ventilation of cadaver lungs with AG induces pulmonary injury in this model. retrieval of donor lungs from circulation-arrested cadavers has potential for increasing the pulmonary donor pool.

Risk factors for early death in patients awaiting heart-lung or lung transplantation: experience at a single European center.

BACKGROUND: Our purpose was to establish whether patients on the waiting list for heart-lung or lung transplantation had different survival rates according to diagnosis and to determine the specific variables responsible for early death. METHODS: Between 1988 and 1996, 278 patients were placed on the waiting list for organ transplant. Diagnoses were pulmonary vascular disease in 128, parenchymal disease in 141, and retransplantation in 9 patients. Eighty patients received transplants, 100 patients died awaiting transplantation, and 98 patients are still awaiting transplantation. Univariate and multivariate analyses of risk factors for early death on the waiting list were performed. Patients still listed < or =6 months (n=24), transplanted < or =6 months (n=37), or in the retransplantation group (n=9) were excluded. Of the remaining 208 patients, 52 died < or =6 months and 156 survived >6 months. RESULTS: Patients with primary pulmonary hypertension, pulmonary fibrosis, or cystic fibrosis had statistically significantly lower survival rates at 6, 12, and 24 months (31%, 36% and 26%, respectively, at 24 months) than patients with Eisenmenger's syndrome and chronic obstructive pulmonary disease (76% and 71%). Patients with Eisenmenger's syndrome who died < or =6 months had significantly higher systolic pulmonary artery pressure (134+/-39 vs. 108+/-25 mmHg) and pulmonary vascular resistance (1928+/-1686 vs. 1191+/-730 dyn/sec/cm(-5)) than those who survived longer. Patients with pulmonary fibrosis who died < or =6 months had significantly lower forced vital capacity (36+/-15 vs. 47+/-13% predicted), forced expiratory volume (37+/-14 vs. 48+/-14% predicted), room air PO2 (42+/-11 vs. 50+/-11 mmHg), and room air O2-saturation (78+/-10 vs. 84+/-8%) than those who survived longer. In the multivariate analysis, only the type of pathology was a significant risk factor for death after being on the waiting list < or =6 months. CONCLUSIONS: Certain pathologies and variables are risk factors for early death in patients on the waiting list. This information may be used to allocate specific donor organs to patients in greater need.

Orthotopic heart transplantation: standard versus bicaval technique.

We compared orthotopic heart transplantation (HT) by bicaval technique with the standard technique. Between January 1995 and December 1997, 117 patients underwent 118 HTs; 71 patients (15 women and 56 men) had 72 HTs by standard technique and 46 patients (9 women, 37 men) underwent HT using bicaval procedures. Preoperative parameters were similar in both groups; 5 patients who underwent the standard technique and no patients who underwent bicaval procedures required permanent pacemakers (p = NS). Isoproterenol infusion was significantly longer in the standard technique. Major perioperative arrhythmias (ventricular tachycardia and fibrillation, asystole) appeared in 8.2% and 7.0% of standard and bicaval HTs, respectively; atrial fibrillation appeared in 13.1% and 4.6%, respectively (p = NS). At 1 month, mitral and tricuspid regurgitation rates were higher in the standard group (p = NS); at 1 year only tricuspid regurgitation was still higher (p = NS). Right atrial pressure, Wood units, cardiac output, and cardiac index were examined (p = NS). At multivariate analysis, interaction between preoperative Wood units and transplant type was elicited for Wood units at 1 month and for right atrial pressure at 1, 3, and 6 months. In the high resistance subgroup, the patients who underwent bicaval procedures had higher resistances at 1 month. In the low resistance subgroup, right atrial pressure was higher in patients who underwent standard techniques at 1, 3, and 6 months follow-up. Thus, bicaval HT was found to be safe, without surgically related complications, it provoked significantly less blood loss, and required less isoproterenol use. No significant advantages were observed in conduction disturbances and major arrhythmias or regarding the need for temporary or permanent pacemakers.

Expression of proliferating cell markers in normal and diseased human hearts.

Proliferating cell nuclear antigen (PCNA) myocyte expression and histopathologic features related to its occurrence were investigated in normal and diseased hearts of adult humans using both immunohistochemical and Western blotting techniques. Ki67 Western blotting was also performed in the same samples used for PCNA blotting. Two hundred seventy-one endomyocardial biopsies, and 15 adult, 1 embryonic and 2 fetal hearts were studied. The biopsies were from normal donor hearts (n = 71), patients with cardiomyopathy and myocarditis (n = 64), and patients with transplantation with (n = 106) and without (n = 30) acute rejection of any grade. The 15 hearts were from 1 heart donor, and from patients with cardiomyopathy (n = 5), valvular heart disease (n = 2), ischemic heart disease (n = 4), amyloidosis (n = 1) and transplantation with acute rejection (n = 2). The PCNA labeling index was plotted against myocyte hypertrophy, inflammatory infiltrates and binucleation index. The PCNA labeling index ranged from 2 to 9% in embryonic and fetal hearts. PCNA was expressed by 1 to 2% of myocyte nuclei in 12% of normal heart biopsies, 1 to 5% of myocyte nuclei in 28% of cardiomyopathy and myocarditis biopsies, and by up to 8% of myocyte nuclei in 53% of biopsies of patients with transplantation, independently of the presence and degree of acute rejection. In the latter biopsies and in myocarditis, some inflammatory cells also showed PCNA expression. PCNA positive myocytes were both mono- and binucleated, and there was no correlation between binucleation and PCNA labeling indexes. Ki67 and PCNA blotting confirmed immunohistochemical results.(ABSTRACT TRUNCATED AT 250 WORDS)

Canine double-lung transplantation with cadaveric donors.

If lungs could be retrieved from cadavers after circulatory arrest, the critical shortage of donors for lung transplantation might be alleviated. To assess gas exchange after transplantation of lungs from cadaveric donors, we performed double-lung transplantation through sequential thoracotomies in 12 dogs. Donors were sacrificed by intravenous pentobarbital injection and then ventilated with 100% oxygen. Lungs were harvested 2 hours (n = 6) or 4 hours (n = 6) after death and flushed with 2 L modified Euro-Collins solution. Recipients underwent sequential right and left lung transplantation; they were then monitored while under anesthesia for 8 hours, with adjustments of the fraction of inspired oxygen. Nine of 12 recipients survived the 8-hour study period. Four of six dogs with cadaveric lungs retrieved 2 hours after death survived; deaths were from pulmonary embolism at 6 hours and pulmonary edema at 2 hours. Five of six dogs with cadaveric lungs retrieved 4 hours after death survived; one died of hypoxia during implantation of the left lung, while dependent on the right lung graft. Postoperative hemodynamic and gas exchange parameters were similar in both groups. Alveolar-arterial oxygen gradient rose significantly compared with baseline 1 hour after transplantation in both groups (462 +/- 60 vs 38 +/- 31 mmHg for 2-hour group, p < 0.0001, and 484 +/- 63 vs 38 +/- 14 mmHg for 4-hour group, p < 0.0002). By 8 hours after operation, the gradients had significantly decreased in both groups (105 +/- 37 mm Hg for 2-hour group and 146 +/- 53 mm Hg for 4-hour group) and were similar to baseline values. Extravascular lung water also rose significantly 1 hour after transplantation (15.7 +/- 2.8 vs 7.9 +/- 0.5 ml/kg for 2-hour group, p < 0.02, and 16.9 +/- 1.2 vs 6.6 +/- 0.4 ml/kg for 4-hour group, p < 0.0001) and decreased gradually during the 8-hour study period. Donor lungs retrieved at 2 and 4 hours postmortem afford similar recipient outcomes. Improvement in alveolar-arterial oxygen gradient and reduction in extravascular lung water during the study period imply that the ischemia-reperfusion injury induced by this model is reversible. If this approach could be safely introduced to clinical practice, substantially more transplant procedures could be performed.

Lung retrieval from cadaver donors with nonbeating hearts: optimal preservation solution.

BACKGROUND: We have previously studied the time course of pulmonary cell viability, ultrastructural damage, and adenine nucleotide metabolites after circulatory arrest in a rat model to investigate the feasibility of lung retrieval for transplantation from cadavers. This study was designed to investigate the effect of hypothermic flush and subsequent 4-hour storage with either modified Euro-Collins or University of Wisconsin solution on lungs retrieved 4 hours after death. METHODS: Ninety-six Sprague-Dawley rats were sacrificed by intraperitoneal injection of pentobarbital. Control lungs were flushed immediately after sacrifice and stored for 4 hours. Rats in the experimental groups were sacrificed, and then their lungs were either ventilated with 100% oxygen or not ventilated for 4 hours before flushing with either Euro-Collins or University of Wisconsin solution followed by 4-hour hypothermic storage. At the end of the storage period, all right lungs were maintained at -70 degrees C and used to determine wet-to-dry weight ratios and adenine nucleotide levels with high-pressure liquid chromatography. Left lungs were assessed for viability with trypan blue dye exclusion. The effect on viability of flushing with Carolina rinse solution after storage was also assessed. RESULTS: The percentage of viable cells in the control group after 4-hour hypothermic storage was 74% +/- 2% in Euro-Collins solution-flushed lungs and 78% +/- 2% in University of Wisconsin solution-flushed lungs. This result was virtually identical to that of lungs retrieved after 4 hours of in situ oxygen ventilation followed by 4 hours of hypothermic storage. Nonventilated cadaver lungs had substantially less viability. Adenosine triphosphate levels were significantly higher in the control group than in the oxygen-ventilated group, which were higher still than those in the nonventilated group. Adenosine triphosphate levels were consistently higher in University of Wisconsin solution-flushed lungs compared with Euro-Collins solution-flushed lungs in all groups. Total adenine nucleotide levels had a similar pattern. Wet-to-dry ratios were significantly lower in the control group (Euro-Collins = 6.27 +/- 0.46, University of Wisconsin = 4.63 +/- 0.07) compared with the oxygen-ventilated (Euro-Collins = 9.80 +/- 0.44, University of Wisconsin = 10.96 +/- 0.60) and nonventilated (Euro-Collins = 9.44 +/- 0.26, University of Wisconsin = 11.54 +/- 1.16; p < 0.0001) groups. CONCLUSIONS: Four hours of circulatory arrest before 4 hours of hypothermic storage had no additional adverse impact on lung viability compared with lungs subjected to 4 hours of hypothermic storage alone, provided nonperfused lungs were ventilated with 100% oxygen. Adenine nucleotide levels were well maintained in oxygen-ventilated cadaver lungs, more so in University of Wisconsin solution-flushed lungs compared with Euro-Collins solution-flushed lungs.

When does the lung die? I. Histochemical evidence of pulmonary viability after "death".

An inadequate number of lung donors for transplantation results in the death of many potential lung recipients awaiting a transplant. Canine experiments in our laboratory have shown effective gas exchange in lungs transplanted from cadaver donors (lungs retrieved after circulatory arrest). The time course of pulmonary cell death after circulatory arrest is unknown. To address this question, we used trypan blue dye exclusion to quantitate lung cell death at postmortem intervals in rats. One hundred ninety Sprague-Dawley rats were killed and separated into four groups: (1) control (n = 10); (2) nonventilated group (n = 60); (3) oxygen-ventilated group (n = 80); and (4) nitrogen-ventilated group (n = 40). At intervals after the animals' deaths, trypan blue was infused into the pulmonary artery followed by fixative, and the left lung was excised. Histologic sections were prepared for each rat lung, and the percentage of nonviable cells was quantified with light microscopy. Control lungs retrieved immediately after death showed little or no uptake of trypan blue dye. In nonventilated rats, 36%, 52%, and 77% of cells were nonviable in lungs retrieved 2, 4, and 12 hours after death, respectively. These results were similar to 34%, 58%, and 71% nonviability at the same intervals in nitrogen-ventilated cadaver rat lungs. Oxygen-ventilated cadaver rats, however, had significantly fewer nonviable lung cells at each time interval: 13%, 10%, and 26%, respectively (p < 0.01). Thus, postmortem mechanical ventilation with oxygen appears to delay lung death in the rat after circulatory arrest. Nonventilated and nitrogen-ventilated cadaver lungs had a similar severity and progression of ischemic injury.(ABSTRACT TRUNCATED AT 250 WORDS)

When does the lung die? II. Ultrastructural evidence of pulmonary viability after "death".

Lung transplantation as a therapy for end-stage lung disease is limited by the paucity of suitable donors. If lungs could be retrieved from circulation-arrested cadavers (that is, after death), then more donors for lung transplantation might be available. This study was undertaken to determine the time course of ultrastructural deterioration of cellular organelles in pulmonary tissue after circulatory arrest and death and to determine the effect, if any, of postmortem ventilation on the development of these ultrastructural changes. Sprague-Dawley rats were sacrificed and then separated into three groups: (1) controls, from which the right lung was immediately harvested (n = 4); (2) ventilated group, in which mechanical ventilation with 100% oxygen was started after death (n = 15); and (3) nonventilated group (n = 15). In the ventilated and nonventilated groups, the right lung was harvested at 2, 4, or 8 hours after death. Portions of the lung from each rat were examined by electron microscopy, and each specimen was assigned a semiquantitative injury score that was based on nuclear chromatin clumping, mitochondrial degeneration, intracellular edema, and cellular membrane integrity. The lung in all four controls was normal. At 4 and 8 hours postmortem, ultrastructural damage was significantly attenuated in rats with oxygen ventilation compared with those in the nonventilated group. The degree of ultrastructural damage observed in the oxygen ventilation group at 2 and 4 hours postmortem was not significantly different from that of normal controls. Thus, mechanical ventilation with oxygen after death appears to preserve lung ultrastructure and may delay cell death. This study supports the hypothesis that lung transplantation from cadaver donors may be feasible.

Predictors of prognosis in patients awaiting heart transplantation.

Patients enrolled in a clinical heart transplantation program were evaluated to identify the predictors of prognosis in patients with advanced heart disease and to optimize timing of heart transplantation. Three hundred eighty-eight subjects were consecutively evaluated from 1985 through 1989. One hundred eighty-four patients (47.5%) had dilated cardiomyopathy; 164 patients (42.2%) had ischemic heart disease; 34 patients (8.8%) had valvular heart disease, and six patients (1.5%) had miscellaneous disorders. In each patient, 45 different parameters were considered. During follow-up (mean, 8.4 months) 166 patients underwent heart transplantation; 99 patients died (heart failure, 66 patients; sudden death, 26 patients; thromboembolism, two patients; noncardiac causes, five patients). The actuarial survival was 83% at 3 months, 77% at 6 months, 73% at 9 months, 70% at 1 year, and 59% at 2 years. The median survival time was 28 months. Analysis by Cox proportional hazard regression model revealed seven independent and significant prognostic factors: etiology (p < 0.05), NYHA class (p < 0.05), third heart sound (p < 0.05), diastolic pulmonary artery pressure (p < 0.05), pulmonary wedge pressure (p < 0.01), mean systemic blood pressure (p < 0.05), and cardiac output (p < 0.05). Cox's analysis allows the computation of patient-specific curves for predictions of residual survival time at any moment during follow-up. Moreover it can be used to calculate a simple prognostic index, which enables stratification of the patient population into three risk classes: patients at high (n = 105), intermediate (n = 160) and low (n = 123) risk of early death. Pairwise comparisons of survival between the classes were significant at 1% level.

Arterial baroreflex modulation of heart rate in patients early after heart transplantation: lack of parasympathetic reinnervation.

BACKGROUND: Orthotopic heart transplantation results in cardiac denervation. The presence of cardiac parasympathetic reinnervation in humans has been widely debated based on the application of differing indirect measures of autonomic control. However no attempt has been made to analyse the reflex heart rate response to baroreceptor stimulation whose occurrence is generally considered a reliable marker of the ability to activate cardiac vagal reflexes. This study tested the hypothesis that the presence of donor heart RR interval lengthening following phenylephrine induced blood pressure increase would be an index of parasympathetic reinnervation. METHODS: Baroreflex sensitivity (BRS) was assessed in 30 patients (mean age 51+/-12 years) 1-24 months after heart transplantation carried out by the standard Lower-Shumway technique. In 6 patients the recipient atrium rate response (P-P interval) to baroreceptor stimulation by phenylephrine was also simultaneously determined by transesophageal recording. RESULTS: None of the 30 patients showed prolongation of RR intervals in the donor heart. The average BRS value was -0.28+/-0.54 ms/mmHg (range -1.3-0.7 ms/mm Hg). In the 6 patients in whom BRS was obtained at both the recipient atrium (P-P) and donor heart (R-R) the changes were 7.6+/-5.7 ms/mm Hg and -0.38+/-0.58 ms/mm Hg respectively (p = 0.02), thus confirming that the absent RR interval lengthening in the donor heart is the consequence of efferent vagal fiber interruption. CONCLUSIONS: The absence of any RR interval prolongation following phenylephrine induced baroreceptor stimulation demonstrates that vagal efferent reinnervation of the donor heart does not occur up to 24 months in patients operated via the standard Lower-Shumway procedure. It is also suggested that analysis of baroreceptor reflexes is a more specific method in the examination of cardiac parasympathetic reinnervation.

Donor lungs from ventilated cadavers: impart of a free radical scavenger.

BACKGROUND: The shortage of donors for lung transplantation may be alleviated with the use of lungs retrieved from cadavers. The purpose of this study was to determine whether a free radical scavenger, dimethylthiourea, would improve the function of lungs retrieved from ventilated cadavers. METHODS: Left lung transplantation was performed in 21 dogs. Donors were sacrificed then ventilated with 100% oxygen. After 2 hours, donor lungs were flushed in a blinded fashion with 2 L of modified Euro-Collins solution, with either dimethylthiourea (n = 10) or saline solution (n = 11) added, then harvested. A donor right lung lobe was perfused with trypan blue vital dye to assess cell viability at harvest and after the transplantation. Percentage of nonviability was similar in the dimethylthiourea and control groups (13 versus 20 at retrieval and 38 versus 41 at graft reperfusion). After transplantation, the right pulmonary artery and bronchus were occluded, rendering the recipient on the pulmonary graft. The recipient's lungs were ventilated for 8 hours, with the inspired oxygen fraction maintained at 0.4. RESULTS: Seven of ten dogs in the dimethylthiourea group survived the 8-hour period, compared with 4 of 11 dogs in the control group. Compared with the control survivors (n = 4) at 8 hours after the operation, the dimethylthiourea survivors (n = 7) had a higher mean arterial oxygen pressure (144 +/- 21 versus 98+/- 12 mm Hg) and cardiac output (2.2 +/- 0.2 versus 1.6 +/- 0.2 L/min) and a lower mean pulmonary vascular resistance (946 +/- 96 versus 1414 +/- 128 dynes.sec-1.cm5, p < 0.05) and extravascular lung water (10.6 +/- 1.2 versus 12.3 +/- 3.2 ml/kg). Differences between groups during the 8-hour period were usually insignificant. CONCLUSIONS: This model imposes a rigorous challenge to the single transplanted lung, and yet cadaver lungs still supported life in half of the recipients. Dimethylthiourea may confer a benefit to recipients of cadaver lungs.