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The coagulation disturbance, typical of septic conditions, is associated to a reduction of clotting factors in plasma with an "acquired" deficiency (from consumption) of protein C. As observed with "purpura fulminans" in neonates affected by congenital protein C deficiency, administration of protein C concentrate has proved to reduce thrombotic manifestations and to improve morbidity and mortality of children with septic shock. The Protein C concentrate is presently utilized as a therapy for patients with a congenital deficiency of protein C and several papers in the literature support the efficacy of protein C concentrate in the treatment of children with meningococcus septicemia, with the aim of correcting the acquired protein C deficiency often seen in septic conditions and shown to be strongly correlated to a higher morbidity and mortality. Protein C, given as a plasma concentrate, can exert its therapeutic actions only after activation once in the blood stream: clinical trials with the use of protein C concentrate failed to show any increased risk of bleeding or related disorders. At our PICU 8 children, with sepsis, septic shock and purpura have been treated with protein C concentrate (Ceprotin); because the plasma protein C level was lower than the normal range (mean value 0.32 IU/ml, range 0.11-0.6 IU/ml). Six children have shown a rapid response to all therapeutic efforts and survived without sequelae and two are died. No adverse reaction was observed during and after Ceprotin administration to all patients.

This report presents the long-term (36 months) neurologic outcome in 12 neonates and 9 children who survived after extracorporeal membrane oxygenation and attempts to identify its prognostic indicators through a prospective study in the pediatric intensive care unit of a university hospital. Outcome assessment, neurodevelopmental tests, electroencephalogram, auditory evoked potentials, visual evoked potentials, and somatosensory evoked potentials, cerebral sonography, or cerebral tomography were evaluated at the end of bypass and at 6, 12, 24, and 36 months after extracorporeal membrane oxygenation. "Before extracorporeal membrane oxygenation" variables (oxygenation index, pH, oxygen arterial partial pressure) and "during extracorporeal membrane oxygenation" variables (pH, oxygen arterial partial pressure, duration of bypass, clotting activated time, electroencephalogram) were also analyzed. A negative neurologic outcome (Glasgow Outcome Score different from "good recovery" or neurodevelopmental score less than 70) 12 months after extracorporeal membrane oxygenation was documented in 8.3% of neonates and in 30% of children who survived. There was no further change in subsequent evaluations (24 and 36 months follow-up). The most abnormal electroencephalogram during extracorporeal membrane oxygenation, the first electroencephalogram, neuroimaging score, and somatosensory evoked potentials after extracorporeal membrane oxygenation treatment were associated with negative neurologic outcome. The study documented that neonates and children treated with extracorporeal membrane oxygenation require long-term follow-up; electroencephalogram, neuroimaging score, and somatosensory evoked potentials have prognostic value for abnormal neurologic outcome.

Amiodarone, an antiarrhythmic drug toxic toward the lung, is metabolized through sequential modifications of the diethylaminoethoxy group to mono- N-desethylamiodarone (MDEA), di- N-desethylamiodarone (DDEA), and amiodarone-EtOH (B2-O-EtOH), whose effects on lung cells are unclear. To clarify this, we exposed rabbit alveolar macrophages to analogs with different modifications of the diethylaminoethoxy group and then searched for biochemical signs of cell damage, formation of vacuoles and inclusion bodies, and interference with the degradation of surfactant protein A, used as a tracer of the endocytic pathway. The substances studied included MDEA, DDEA, and B2-O-EtOH, analogs with different modifications of the diethylaminoethoxy group, fragments of the amiodarone molecule, and the antiarrhythmic agents dronedarone (SR-33589) and KB-130015. We found the following: 1) MDEA, DDEA, and B2-O-EtOH rank in order of decreasing toxicity toward alveolar macrophages, indicating that dealkylation and deamination of the diethylaminoethoxy group represent important mechanisms of detoxification; 2) dronedarone has greater, and KB-130015 has smaller, toxicity than amiodarone toward alveolar macrophages; and 3) the benzofuran moiety, which is toxic to liver cells, is not directly toxic toward alveolar macrophages.

Background and Aims: Transforming growth factor-beta (TGF-beta) system is involved in the control of cell growth and extracellular matrix formation. Previous studies in patients with chronic liver disease have shown that increased TGF-beta expression significantly correlates with the degree of hepatic fibrosis. The aim of our study was to define TGF-beta system expression in hepatic parenchymal cells and its significance in patients with differing extents of chronic liver disease of viral etiology. Methods: Expression of TGF-beta 1, TGF-beta 1 type II receptor (TGF-beta RII) and the Smad signaling pathway was evaluated in consecutive liver sections of 77 patients with chronic liver disease (65 HCV positive and 12 HBV positive). Results were correlated with histological scores and apoptotic activity. Results: TGF-beta 1 was demonstrated in the liver of 30/56 (53.6%) patients with chronic hepatitis and 20/21 (95%) patients with cirrhosis, but in none of the 20 normal livers. Positive cytokine reaction was seen both in stromal cells and hepatocytes. Expression of TGF-beta RII and Smad proteins showed a distribution pattern similar to that of TGF-beta, with a direct correlation in terms of immunoreactivity extent. A significant correlation was found between parenchymal expression of TGF-beta system and inflammatory and fibrosis scores. No correlation was found with apoptotic index and other morphological, clinical or virological parameters. Conclusions: The TGF-beta system is up-regulated at the ligand, receptor and signaling level in the liver of patients with more active disease. The strong expression of TGF-beta and the Smad pathway in parenchymal cells suggests that hepatocytes, in addition to mesenchymal cells, may play an important role in the progression of liver disease.

BIOSA is a single sheet, two-cuspal-shaped ("bileaflet") glutaraldehyde fixed bovine pericardial valve prosthesis (BP), designed to minimize stress and prevent mechanical failure. We tested this device in the adult sheep model.Seven BIOSA and two Baxter Carpentier-Edwards (Perimount) pericardial BPs, 25 mm in size, were implanted in the tricuspid position of adult sheep. A mid term BIOSA explant (81 days) died of infective endocarditis. The remaining BPs were divided in three early explants (0-3 days: two BIOSA and one Perimount) and five late explants (162-189 days: four BIOSA and one Perimount). Protocol of the study included gross examination, mammography X-ray (score 0-4), histology, scanning (SEM) and transmission (TEM) electron microscopy and atomic absorption spectroscopy.(a) Early explants: The mesothelium was detached, collagen-elastic fibers and pericardiocytes of the fibrosa showed optimal preservation. Calcium content in BIOSA BPs was 6.22 mg/g dry weight (mean) versus 7.75 mg/g of the Perimount BP. (b) Late explants: At naked eye all BPs showed regular cusp pliability and coaptation, without tears, perforations, fibrous pannus or calcific deposits. X-ray was either negative (three BPs) or exhibited score 1 (two BPs). Microscopic features were excellent both in terms of collagen-elastic fibers preservation and absence of inflammation. The calcium content was 4.95 mg/g dry weight (mean) in BIOSA BPs versus 5.29 mg/g in the Perimount BP.Tissue characteristics of BIOSA BPs were optimal, without difference with Perimount BPs and in this animal model no case of structural valve deterioration occurred in the long term.

Background Primary tissue failure, which is mainly caused by calcification, is still the limiting factor in the long-term outcome of heart valve bioprostheses. Even though the precise nature of this process is not fully understood, in vitro tests have been developed to reproduce and predict calcification for individual bioprostheses. Methods In vitro calcification testing was performed by using an accelerated pulsatile valve tester which was adapted for testing stented as well as stentless bioprostheses with physiological fluid dynamics. A total of 84 bioprostheses (porcine, pericardial and stentless porcine of different manufacturers) were cyclically loaded at a test rate of 300/min at 37 degrees C within a rapid calcification fluid with CaxP = 130(mg/dl)2 at pH 7.4. Calcification was assessed by microradiography after 12 x 10(6) cycles. In a previous step, holographic interferometry was performed to identify irregularities of valve leaflets in order to predict later calcification. Selected specimens of calcified bioprostheses underwent histology, transmission (TEM) and scanning (SEM) electron microscopy. Tissue mineralization was investigated by coupling SEM, electron microprobe analysis (EMPA) and X-ray powder diffraction (XRPD) methods. Results For all tested bioprostheses, a significant calcification was achieved within 4 to 6 weeks of ongoing testing, and the degree of calcification increased with time. A significant correlation between calcification and leaflet irregularities (detected by holographic interferometry) was found (r = 0.80, p = 0.001). Calcification varied between individual bioprostheses, and significant differences were detected for different groups (calculated as percentage of total leaflet area, mean +/- SD): porcine stented (37.3 +/- 12.0%), bovine stented (23.0 +/- 8.9%), porcine stentless (16.2 +/- 7.6%). Histological and ultrastructural investigation showed intrinsic calcification involving both the spongiosa and fibrosa with collagen fibrils, interfibrillar spaces and cells as early sites of calcification. There was clear evidence of apatite crystallization, and observations made with in vitro calcification were quite similar to those occurring with in vivo implanted bioprostheses. Conclusion In vitro tests can reproduce intrinsic calcification of bioprostheses even in the absence of viable biologic host factors. Moreover, degree and sites of calcification have become predictable. This enables the development and evaluation of bioprostheses with reduction of animal experiments. From our results obtained with a broad range of available bioprostheses, stented bovine and stentless porcine valves seem to be superior to conventional stented porcine bioprostheses with regard to leaflet calcification.

Flow-volume loop evaluation yields considerable diagnostic information about adult patients with upper airway obstruction. No conclusive data support the reliability of this method in young children with noisy breathing. We used analysis of flow-volume loops at tidal breathing (TB-FV) as a first diagnostic approach to young children presenting with persistent noisy breathing (chronic stridor and/or wheezing). Flexible fiberoptic bronchoscopy was performed to establish a conclusive diagnosis and was used to verify the accuracy of the preliminary functional localization of the airway obstruction causing noisy breathing. The physician conducting pneumotachography was blinded to the bronchoscopic findings in the study, and the investigators conducting bronchoscopy were blinded to the pneumotachographic findings. Through a 6-yr period, 113 consecutive young children (ranging in age from 15 to 48 mo) with noisy breathing were enrolled in the study. Three morphologically abnormal TB-FV patterns, as compared with the normal round-shaped TB-FV loops obtained with 15 healthy children, were identified in 110 patients. A TB-FV pattern of inspiratory fluttering was found in 26 subjects and in the first 3 yr of the study was always associated with an endoscopic diagnosis of isolated laryngomalacia. Subsequently, this pattern was used to diagnose isolated laryngomalacia in 18 other infants, in whom endoscopy was avoided. Of infants with endoscopic evidence of airway obstruction ranging from the glottis to the mainstem bronchi (49 subjects), all but three showed a TB-FV loop pattern characterized by expiratory-limb flattening. A concave expiratory loop, with early expiratory peak flow and low flow at low volume, was invariably associated with peripheral bronchoconstriction, without endoscopic evidence of anatomic abnormalities (20 cases). In conclusion, TB- FV loop analysis is a noninvasive, accurate method of establishing the site of airway obstruction in young children with recurrent stridor and/or wheezing. Clinical use of this method may provide interesting pathophysiologic information and may be useful in addressing the diagnostic management of such children.

In hepatitis C virus (HCV) infection, mechanisms responsible for liver cell damage are still poorly understood and both necrosis and apoptosis may be operative. By using terminal deoxynucleotydil transferase-mediated d-UTP-biotin nick-end labeling (TUNEL) we have evaluated and quantified apoptosis in liver biopsy specimens from 61 patients with chronic hepatitis C. All patients had detectable apoptotic cells in the liver. Presence of increased apoptotic activity was confirmed in selected cases by electron microscopy and by DNA gel electrophoresis. The amount of liver cell apoptosis expressed as apoptotic index, ranged between 0.01% to 0.54% and showed a positive correlation with histological activity grading (P

This paper examines the removal from the airways of Curosurf, a commercial surfactant derived from porcine lungs, administered at pharmacological concentrations to newborn or adult animals. Curosurf was labelled by the addition of radioactive dipalmitoyl phosphatidylcholine (DPPC) and administered intratracheally to newborn and adult rabbits at a dose of 200 mg x kg(-1) body weight. The disappearance of DPPC from the airways and its appearance in alveolar macrophages, lung parenchyma, lamellar bodies, serum, liver, kidneys and brain was then studied for 24-48 h. The in vitro degradation of Curosurf DPPC by alveolar macrophages was also studied. During the first 3 h after instillation, large amounts of Curosurf left the airways and became associated with tissue, indicating that it mixed rapidly with the endogenous pools of surfactant. A fraction of administered DPPC became associated with the lamellar bodies, suggesting that Curosurf can be recycled. Curosurf administration did not stop the secretion of endogenous surfactant. Very little intact radioactive DPPC could be recovered at any time in alveolar macrophages, however, macrophages have the ability, in vitro, to degrade Curosurf. Newborn rabbits lose Curosurf from the lungs at a slower rate than adult rabbits. One and two days after instillation, organic extracts from the liver, kidney, brain and serum contained small but measurable amounts of radioactivity. These results indicate that Curosurf rapidly enters the pathways of surfactant metabolism and that alveolar macrophages may play an important role in the catabolism of Curosurf.

Hepatic ischaemia/reperfusion is characterized by circulatory and metabolic derangement, liver dysfunction, and tissue damage. To evaluate the role of L-arginine, a substrate of nitric oxide, in ischaemia/reperfusion injury, total liver ischaemia was induced for 120 min in 22 Landrace x Large White female pigs, which were randomly assigned to a treatment group (10 animals) or a control group (12 animals). An L-arginine bolus (540 mg/kg i.v.) was administered to the treatment group 1 h before clamping the hepatic hilum, at clamping, at reperfusion, and at 1 and 2 h after reperfusion. The control animals received normal saline and an i.v. infusion. Liver function tests and analysis of serum, erythrocyte, and tissue malondialdehyde contents were performed at commencement of laparotomy, before reperfusion, and at 30 min and 7 days after reperfusion. Liver biopsies were taken at laparotomy, at 30 min, and at 7 days after reperfusion for histological and ultrastructural examination. Assessment of apoptosis included in situ end-labelling analysis and DNA gel electrophoresis. Survival at 7 days was better in the treated animals than in the controls (9/10 vs. 7/12). Tissue malondialdehyde content, aspartate aminotransferase, and lactate dehydrogenase levels were lower in the treatment group, in which morphological changes were significantly less evident than in the controls 30 min after reperfusion. At 7 days, differences between the groups with respect to cell integrity were apparent only on ultrastructural analysis. Glycogen content, 7 days after reperfusion, was higher in the treatment group than in the controls: 70.25 per cent vs. 21.66 per cent positive hepatocytes (score 3 vs. score 1). Multiparametric analysis showed fewer apoptotic cells in the treatment group at all times. Our data show that the administration of L-arginine reduces damage to liver tissue after ischaemia/reperfusion injury in a pig model. This may be explained not only by the known vasodilator, anti-aggregation, and superoxide inactivation effects of increased nitric oxide release, but possibly also by some other action of L-arginine, such as its influence on cellular metabolism.

The aim of this study was to evaluate the effect of inhaled nitric oxide (NO) in newborns with acute hypoxaemic respiratory failure and the impact of this NO therapy on survival and the need for extracorporeal membrane oxygenation (ECMO). A cohort of newborns with a gestational age of > or = 34 weeks and an oxygenation index (OI) > 25 were prospectively evaluated. Patients were given NO at an initial dose of 10 parts per million (ppm). Oxygenation parameters were evaluated prior and during NO inhalation. From January 1994 to December 1996, 20 infants were enrolled in the study. Based upon their outcome, patients were divided into two groups: survivors with no need for ECMO, group A (n=8) and survivors requiring ECMO or nonsurvivors, group B (n=12). All infants approached or met ECMO criteria before NO inhalation. Eight patients (40%) were successfully managed with NO and conventional treatment (group A). Newborns in this group showed a rapid and sustained improvement of systemic oxygenation during NO inhalation. Mean arterial oxygen tension (Pa,O2) increased significantly from 4.5 kPa (34 mmHg) (95% confidence interval (95% CI) 1.9-7.1 kPa (14.4-53.7 mmHg)) to 10.1 kPa (75.7 mmHg) (95% CI 6.5-13.6 kPa (49.1-1023 mmHg)) after 1 h and was 9.0 kPa (67.7 mmHg) (95% CI 7.1-11.0 kPa (53.1-82.4 mmHg)) at 24 h. Conversely, none of the oxygenation parameters improved in the 12 patients who ultimately required ECMO or died (group B). The results indicate that inhaled nitric oxide can improve systemic oxygenation in newborns with acute respiratory failure and may reduce the need for extracorporeal membrane oxygenation support in candidates. Lack of a rapid response to nitric oxide may be an early predictor of unfavourable short-term outcome, prompting a move towards alternative treatments.

This paper reports on some pharmacological and biological properties of 22-mer antisense oligodeoxynucleotides which contain an L-deoxyribonucleoside at each terminus. Compared with natural compounds, of which they retain the DNA hybridizing ability and the cell uptake mechanism, the L-22-mers exhibited an increased resistance to phosphodiesterase degradation, an apparent higher intracellular concentration and a longer intracellular half life. Antiviral activity was not prominent.

Congenital diaphragmatic hernia (CDH) with severe respiratory failure is still associated with significant mortality. Modern treatment of CDH is now widely accepted to be delayed repair after stabilization. Availability of Extracorporeal Membrane Oxygenation (ECMO) led up to real improvement in survival. Several others modalities have been recently used in attempting to reduce the need for ECMO or, otherwise, to improve outcome. Multicenter controlled trial of high-frequency oscillatory ventilation (HFOV), exogenous surfactant replacement, nitric oxide (NO) inhalation and, more recently, liquid ventilation have been reported. We describe four cases of CDH treated in our ECMO-centre from 1993 to date, 25% surviving. One patient died by pulmonary hypertension and multiorgan failure while on ECMO; one by pulmonary hypertension and cardiac failure and one by sepsis, both ones far from effective ECMO weaning. All patients underwent extracorporeal bypass because of Oxygenation Index (OI) ranging 65-215. Venovenous has been always made but one patient needed early switching on venoarterial. Several trials with surfactant and nitric oxide were performed during extracorporeal bypass. In survived patient, diaphragmatic defect was repaired out of ECMO. Patients survived to the weaning underwent vascular reconstruction. Our ECMO data confirm worse prognosis for CDH rather than other ECMO requiring diseases (we report 66.7% surviving in overall ECMO application); we underline real improvement by using alternative therapies together with extracorporeal bypass and primary role of OI as predicting index for ECMO.

Extracorporeal membrane oxygenation (ECMO) has become a nearly standard treatment for neonates with refractory hypoxemic respiratory failure due to various disease. Even though in the non-neonatal age the experience is less extensive, an increased widespread interest on the possible applications in children with severe life-threatening respiratory or cardiovascular insufficiency is well documented in the literature. General contraindications include presence of active bleeding, underlying lethal disease, congenital malformations, or severe brain damage. Whilst in the neonatal population common entry criteria have been widely accepted, the identification of precise parameters capable to predict mortality and thus indicating an ECMO support in older patients are still lacking. At present, nonetheless, more than 10.000 newborns and 1.000 children with severe respiratory insufficiency at high mortality risk have received an ECMO treatment, with a survival rate of more than 80% and 50%, respectively. The initial results of our ECMO program for both neonatal and pediatric patients with refractory respiratory failure are encouraging, both in terms of mortality and morbidity, and they will be briefly discussed.

Advance in the science and technology of neonatal and pediatric critical care have resulted in improved outcome for high risk newborn and children. Effective interhospital transport programmes are necessary for the appropriate use of resources and has become an integral component of regionalized perinatal care. It is now well established that use of an organized neonatal and pediatric transport team results in a fall in mortality and morbidity of infant. The American College of Obstetrician and Gynecologist and, recently, American Academy of Pediatrics published guidelines and recommendations for safe interhospital transfer of neonates, infants and children. Training of personnel, selection of equipment, organization and communication between hospitals are critical elements of a successful transport system. We present an overview of the role, principles and operating procedures of such neonatal-pediatric transport team and the basis of clinical stabilization before and during transfer. We also discuss data of the first 17 month experience of the Neonatal-Pediatric Transport Service of the Department of Pediatrics, University of Padua.

Pediatric intensive care units (PICUs) have been developed to provide intensive care for children between post-neonatal age and adolescence. These units have largely been developed in North America, mainly in tertiary hospitals. In Italy, critically ill children are still often nursed on adult ICU's, where medical and nursing staff often lack pediatric training. Here we report the first 5-year experience of the multidisciplinary PICU developed at the Department of Pediatrics, University of Padua, focusing on PICU and patients characteristics, as well as on the evaluation of outcome by means of the Pediatric Risk of Mortality (PRISM) score.

Inhaled nitric oxide (NO) has been recently proposed as a new treatment in newborns and children with severe hypoxemic respiratory failure. Differently from other vasodilators, inhaled nitric oxide selectively lowers pulmonary vascular resistance and pulmonary arterial pressure, and improves the ventilation/perfusion matching by directing pulmonary blood flow toward better ventilated areas, ultimately improving systemic oxygenation. In our experience, we have observed that inhaled NO may acutely ameliorate gas exchange in patients with severe respiratory failure. This may allow a reduction of both ventilatory parameters and fraction of inspired oxygen, thus limiting further damage to the lungs. Nonetheless, the underlying disease and the clinical conditions before NO treatment seem to maintain a crucial role in the ultimate prognosis of these patients. Further studies are needed in order to better define indications, dosages, and safety of nitric oxide treatment, and to verify its authentic prognostic value in neonates and children with acute respiratory failure.