[Surfactant treatment of newborn infants receiving continuous positive airway pressure treatment]

INTRODUCTION

The purpose of this study was to examine the efficiency of a single dose of fast-acting exogenous surfactant (Curosurf) given to premature babies with progressive respiratory insufficiency. Curosurf was given as early rescue therapy during a brief intubation (INSURE method: INtubation-SURfactant-Extubation) during treatment with nasal Continuous Positive Airway Pressure (CPAP).

MATERIALS AND METHODS

Retrospective study of 115 premature infants with respiratory distress syndrome born and treated at Odense University Hospital during the years 1999 to 2004. The criterion for surfactant treatment was a decrease in the arterial/alveolar oxygen tension ratio (or corresponding values for the fraction of inspired oxygen) below 0.36 in infants with gestational age (GA) < 30 weeks and 0.22 in more mature infants.

RESULTS

The primary end point was survival during the first week of life without mechanical ventilation. This end point was reached by 51% of the infants with GA < 30 weeks. However, the effect proved to be GA-dependent, increasing from 22% in infants with a GA of 24-25 weeks to 86% in week 29. Seventy percent survived to be discharged. In infants with GA > 29 weeks the effect was 87%, and all survived.

CONCLUSION

The effect of surfactant therapy administered per the INSURE method is GA-dependent, and the method works best after GA week 25. The question is whether earlier therapy will increase its efficiency or the method has reached its limit.

Biologically active lipids promote trafficking and membrane association of Rac1 in insulin-secreting INS 832/13 cells

Despite emerging evidence to suggest that glucose-stimulated insulin secretion (GSIS) requires membrane targeting of specific small G proteins (e.g., Rac1), very little is known with regard to the precise mechanisms underlying subcellular trafficking of these proteins in the glucose-stimulated islet beta-cell. We previously reported activation of small G proteins by biologically active lipids via potentiation of relevant GDP/GTP exchange activities within the beta-cell. Herein, we studied putative regulatory roles for these lipids in the trafficking and membrane association of Rac1 in cell-free preparations derived from INS 832/13 beta-cells. Incubation of INS 832/13 cell lysates with polyphosphoinositides (e.g., PIP(2)), phosphatidic acid, phosphatidylcholine, and phosphatidylserine significantly promoted trafficking of cytosolic Rac1 to the membrane fraction. Lysophosphatidic acid, but not lysophosphatidylcholine or lysophosphatidylserine, also promoted translocation and membrane association of Rac1. Arachidonic acid, diacylglycerol, calcium, and cAMP failed to exert any clear effects on Rac1 translocation to the membrane. Together, our findings provide the first direct evidence in support of our recent hypothesis (Kowluru A, Veluthakal R. Diabetes 54: 3523-3529, 2005), which states that generation of biologically active lipids, known to occur in the glucose-stimulated beta-cell, may mediate targeting of Rac1 to the membrane for optimal interaction with its putative effector proteins leading to GSIS.

Effect of PEGylation on the stability of liposomes during nebulisation and in lung surfactant

Oral inhalation of anticancer drugs or drug delivery system is a novel therapeutic approach in the treatment of lung cancer and requires formulations which are sufficiently stabile during nebulisation and subsequent interaction with the surfactant lining of the lungs. In this study, we assessed the stability of plain and PEGylated transferrin-conjugated liposomes after nebulisation using two different nebulisers (i.e., air-jet and ultrasonic type). Furthermore, the integrity of the liposomal membranes was assessed after incubation in commercial lung surfactant solutions (Alveofact). All liposomal formulations showed no significant changes in their size after nebulisation, independent of the type of nebuliser or the liposomal formulation, respectively. However, PEGylation was of advantage when it came to interactions between liposomes and the surfactant lining of the lungs. PEGylated liposomes were significantly more stable and retained > 80% of their drug load over 48 h, which is more than sufficient time for the drug carriers to be taken up by transferrin receptor over-expressing cancer cells in the lung. In conclusion, PEGylated and plain Tf-conjugated liposomes are stable enough to undergo nebulisation in the course of an inhalational therapy, but PEG-stabilisation results in a higher degree of membrane integrity in lung surfactant.

Saponin-adjuvanted particulate vaccines for clinical use

Saponins are well recognised as potent immune stimulators, but their applicability as vaccine adjuvants have been limited due to associated toxicity. Formulation of saponin adjuvant with cholesterol and phospholipid produces the particulate ISCOMATRIX adjuvant, and when antigen is also contained within the particle, an ISCOM vaccine is produced. These particulate vaccines retain the adjuvant activity of the saponin component but without toxicity. Saponin-adjuvanted particulate vaccines have significant potential as a novel strategy in vaccine development. This review discusses (i) recent methodologies which have attempted to increase the flexibility and applicability of this technology by modifying either the vaccine composition or the mode of formulation; (ii) recent evaluations of these technologies for inducing protection against infectious diseases and as cancer immunotherapeutics.

A phase II trial of perifosine, an oral alkylphospholipid, in recurrent or metastatic head and neck cancer

BACKGROUND

Novel, effective therapies are warranted in the management of recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN). Perifosine is an oral alkylphospholipid that inhibits AKT phosphorylation and has shown preclinical antitumor activity in head and neck cancer cell lines and xenografts.

PATIENTS AND METHODS

We conducted a phase II trial of perifosine in patients with incurable, recurrent or metastatic SCCHN. Previous therapy for recurrent or metastatic disease was limited to no more than one prior chemotherapy and one prior targeted/biologic agent regimen. Patients had to have measurable disease, Eastern Cooperative Oncology Group performance status 0-2, and adequate laboratory parameters. Perifosine was given as a loading dose of 150 mg every 6 hours x 6 doses orally in the first two days, with antiemetic prophylaxis, followed by 100 mg/day orally without interruption. Administration via gastrostomy tube was allowed. Tumor response was assessed every two cycles (eight weeks). Biomarkers in pathways potentially affected by perifosine, including AKT, P-AKT, P38, p53 and p21 were measured on tumor tissue by immunohistochemistry by manual and automated methods.

RESULTS

Nineteen patients were enrolled. No objective responses were observed. One patient had stable disease as best response and 18 patients progressed at first evaluation. The median overall survival time was 5.5 months and the median progression-free survival time was 1.7 months. The most frequent toxicities were gastrointestinal (constipation, nausea, vomiting) and fatigue. One patient developed grade 4 anorexia. Although the sample size was small, a significant correlation was detected between high expression of P38 and AKT in baseline tumor tissue and better survival.

CONCLUSIONS

Perifosine in the doses and schedule used lacks single-agent activity in SCCHN. Our data do not justify further investigation of perifosine as a single agent in SCCHN.

Immunogenicity of Liposomes Containing Lipid Core Peptides and the Adjuvant Quil A

PURPOSE

The purpose of this study was to investigate the immunogenicity of liposomes containing mannosylated lipid core peptide (manLCP) constructs, both in vitro and in vivo, with or without the addition of the immune stimulating adjuvant Quil A.

METHODS

Mouse bone marrow dendritic cells (BMDC) were cultured with liposome formulations for 48 h, and the resulting level of BMDC activation was determined by flow cytometry. BMDC pulsed with liposome formulations were incubated with 5,6-carboxyfluoroscein diacetate succinimidyl ester-labeled T cells for 72 h and the resulting T cell proliferation was determined by flow cytometry. To investigate the immunogenicity of formulations in vivo, groups of C57Bl/6J mice were immunized by subcutaneous injection, and the resulting antigen-specific cytotoxic and protective immune responses toward tumor challenge evaluated.

RESULTS

Despite being unable to demonstrate the activation of BMDC, BMDC pulsed with liposomes containing manLCP constructs were able to stimulate the proliferation of naïve T cells in vitro. However, in vivo only liposomes containing both manLCP and Quil A were able to stimulate a strong antigen-specific cytotoxic immune response. Liposomes containing manLCP and Quil A within the same particle were able to protect against the growth of tumor cells to a similar level as if the antigen was administered in alum with CD4 help.

CONCLUSION

ManLCPs administered in liposomes are able to stimulate strong cytotoxic and protective immune responses if Quil A is also incorporated as an adjuvant.

Evaluating bowel wall vascularity in Crohn’s disease: a comparison of dynamic MRI and wideband harmonic imaging contrast-enhanced low MI ultrasound

This was a prospective comparison of dynamic MRI (1.5 T) and echo-signal enhanced ultrasound in evaluating vascularization in thickened bowel walls cases of Crohn's disease. Twenty-one patients with histologically confirmed Crohn's disease and bowel wall diameters >5 mm were examined by MRI and ultrasound (US). MR sequences: T1w fl2D, T2w, FLASH T1w post-contrast media (CM) applications with fat saturation were used. Dynamic Turbo-FLASH T1w sequences were acquired in the area of maximal thickening of the ileal wall every 1.5 s post-CM application for a total duration of 1 min. US was performed after the application of 1.2 ml of echo-signal enhancer. Contrast uptake was measured by the semiquantitative score and brightness analysis in regions of interest (ROI). Clinical and laboratory findings including Crohn's disease activity indices were documented; MRI and US parameters were correlated. The length of sonographically documented lesions (122+/-75 mm) correlated significantly with the length of thickened bowel segments in MRI (128+/-76 mm; r=0.466; P=0.033). The maximum percent signal enhancement in the terminal ileum at ultrasound (217.5+/-100.1%) showed a high correlation with the findings of MRI (262+/-108%; r=0.623; P=0.003). With both methods, a plateau phase was observed. US and MRI are capable of evaluating local vascularization in the bowel wall objectively.

Is microbubble-enhanced ultrasonography sufficient for assessment of response to percutaneous treatment in patients with early hepatocellular carcinoma?

The objective of this study was to assess the efficacy of contrast-enhanced ultrasonography (CEUS) with SonoVue to evaluate the response to percutaneous treatment (ethanol injection/radiofrequency) of hepatocellular carcinoma in comparison with spiral computed tomography (CT) immediately and 1 month after treatment. Forty-one consecutive cirrhotic patients with early stage tumor (not suitable for resection) were included. Spiral CT and CEUS were performed in all patients before treatment, in the following 24 h, and 1 month later. The results of each examination were compared with the 1-month spiral CT, considered the gold standard technique. The 24-h CEUS and the 24-h spiral CT sensitivity to detect residual disease were 27% and 20%, respectively. The 24-h CEUS and the 24-h spiral CT positive predictive value of persistent vascularization detection were 75% and 66%, respectively. The 1-month CEUS detected partial responses in ten out of 11 cases (91% sensitivity, 97% specificity, 95% accuracy). Spiral CT and CEUS performed in the 24 h following treatment are slightly useful to evaluate therapeutic efficacy. The 1-month CEUS has a high diagnostic accuracy compared with spiral-CT in the usual assessment of percutaneous treatment response.

The effect of hyaluronic acid and phospholipid based lubricants on friction within a human cartilage damage model

The lubricating abilities of different formulations of high molecular weight hyaluronic acid (HA), dipalmitoyl phosphatidylcholine (DPCC) and mixtures of both HA and DPCC were assessed in an in vitro model. Levels of start-up friction were determined using an osteoarthritis (OA) damaged human cartilage model set within a specially designed friction rig. To examine the long term benefits of HA, the extent of penetration of HA into cartilage tissue was investigated using fluorescently labelled HA and confocal microscopy. It was found that in this model, all formulations of HA and the majority of DPCC lubricants reduced friction (HA 5 and 10 mg ml(-1), DPPC 200 mg ml(-1) reductions of 51.9%, 46.7% and 46.5% respectively), compared to a Ringers solution control. Lubrication was found not to be concentration dependent for HA formulations, but concentration was key for DPCC lubrication (100 mg ml(-1) reduced friction by only 15.9%). By combining HA and DPCC (HA/DPPC; 5 mg ml(-1)/100 mg ml(-1) and 10 mg ml(-1)/200 mg ml(-1)), a further improvement was noted (69.5% and 61.9%, respectively) as the mean levels of friction were reduced by up to a further 17% than the most effective individual formulation (HA 5 mg ml(-1)). Penetration of HA into bovine cartilage by up to 300 microm from the surface was observed over a 48 h period. It was observed that HA specifically targeted the chondrocytes as it was primarily found within the lacunae surrounding the cells.

Local immune responses following nasal delivery of an adjuvanted influenza vaccine

A key barrier to producing effective nasal immunisations is the low efficiency of uptake of vaccines across the nasal mucosa. Using a recently developed cannulation system, we examined the antibody response induced by nasal immunisation with an ISCOMATRIX influenza vaccine. This showed for the first time, that following nasal vaccination, specific antibodies enter the circulation of primed animals via the draining lymphatics as a wave that peaks approximately 5-6 days after vaccination. These antibodies included some of the IgA isotype and possessed functional haemagglutination inhibition activity. These responses, though small, were induced using a very simple delivery system, emphasising the applicability of this cannulation model for evaluation of excipients and adjuvants aimed at improving intranasal vaccine efficacy.

Novel nanoliposomal CPT-11 infused by convection-enhanced delivery in intracranial tumors: pharmacology and efficacy

We hypothesized that combining convection-enhanced delivery (CED) with a novel, highly stable nanoparticle/liposome containing CPT-11 (nanoliposomal CPT-11) would provide a dual drug delivery strategy for brain tumor treatment. Following CED in rat brains, tissue retention of nanoliposomal CPT-11 was greatly prolonged, with >20% injected dose remaining at 12 days for all doses. Tissue residence was dose dependent, with doses of 60 microg (3 mg/mL), 0.8 mg (40 mg/mL), and 1.6 mg (80 mg/mL) resulting in tissue half-life (t(1/2)) of 6.7, 10.7, and 19.7 days, respectively. In contrast, CED of free CPT-11 resulted in rapid drug clearance (tissue t(1/2) = 0.3 day). At equivalent CED doses, nanoliposomal CPT-11 increased area under the time-concentration curve by 25-fold and tissue t(1/2) by 22-fold over free CPT-11; CED in intracranial U87 glioma xenografts showed even longer tumor retention (tissue t(1/2) = 43 days). Plasma levels were undetectable following CED of nanoliposomal CPT-11. Importantly, prolonged exposure to nanoliposomal CPT-11 resulted in no measurable central nervous system (CNS) toxicity at any dose tested (0.06-1.6 mg/rat), whereas CED of free CPT-11 induced severe CNS toxicity at 0.4 mg/rat. In the intracranial U87 glioma xenograft model, a single CED infusion of nanoliposomal CPT-11 at 1.6 mg resulted in significantly improved median survival (>100 days) compared with CED of control liposomes (19.5 days; P = 4.9 x 10(-5)) or free drug (28.5 days; P = 0.011). We conclude that CED of nanoliposomal CPT-11 greatly prolonged tissue residence while also substantially reducing toxicity, resulting in a highly effective treatment strategy in preclinical brain tumor models.

[Protective and curative effects of prophylactic administration of pulmonary surfactant on neonatal respiratory distress syndrome]

OBJECTIVE

To evaluate the protective and curative effects of prophylactic administration of pulmonary surfactant (PS) on neonatal respiratory distress syndrome (NRDS).

METHODS

One hundred neonates aged 0.5 h after birth, with the gestational age < 32 w, birth weight < 1500 g, and number of gastric, stable microbubble < or = 7/mm(2) by gastric stable microbubble test (SMT), but without clinical or radiological manifestations of RDS at the admission, were randomly divided into 2 equal groups: prophylactic group (PG), receiving curosurf, a product of PS, immediately after admission; and non-prophylactic group (N-PG), receiving curosurf only after development of RDS.

RESULTS

One hour after the administration of PS, the PaO(2), a/APO(2), pH, and PaO(2) of the PG group were 86.2 mm Hg +/- 8.1 mm Hg, 0.30 +/- 0.04, 7.38 +/- 0.06, and 178 +/- 37, all significantly higher than those of the non-PG group (all P < 0.01), and the PaCO(2) of the PG group was 37.3 mm Hg +/- 9.8 mm Hg, significantly lower than that of the non-PG group (53.6 mm Hg +/- 11.1 mm Hg, P < 0.01). In comparison with the level before the administration of PS (0.75 +/- 0.06), the level of FiO(2) of the 47 pediatric patients receiving mechanical ventilation decreased after the administration of curosurf time-dependently, e.g., was 0.50 +/- 0.09, 0.34 +/- 0.06, and 0.25 +/- 0.07 8, 48, and 96 hours after the administration. In comparison with the level before the administration of curosurf 9.0 +/- 1.0 cm H2O, the level of mean airway pressure (MAP) decreased time-dependently after the administration, e.g., were 7.5 +/- 0.8 and 6.0 +/- 0.3 48 and 96 hours after the administration (all P < 0.01). Compared with that before the administration of curosurf (3.02 +/- 0.2), the X-ray chest score decreased time-dependently after the administration of curosurf, e.g., were 1.89 +/- 0.34, 1.82 +/- 0.33, and 1.17 +/- 0.42 6, 12, and 72 hours after the administration (all P < 0.01). The RDS rate of the PG group was 30%, significantly lower than that of the non-PG group (P < 0.01). The severe case rate of the PG group was 20%, significantly lower than that of the N-PG group (53%, P = 0.01). The mortally of the PG group was 0, significantly lower than that of the non-PG group (P < 0.05). The total times of supplemental oxygen administration, assisted ventilation and hospitalization of the 47 patients with RDS in the PG group were significantly shortened compared with the RDS patients in the N-PG group [(3.6 +/- 1.7) d vs. (5.9 +/- 3.6) d, P < 0.05; (8.6 +/- 5.5 d vs. (14.1 +/- 6.2) d, P < 0.01; and (20.5 +/- 10.0) d vs. (32.8 +/- 17.8) d, P < 0.05).

CONCLUSION

Prophylactic administration of PS to the preterm neonates with high risk of RDS effectively decreases the incidence of RDS, development of severe cases and mortality, shorten the disease course, the duration of supplemental oxygen administration and assisted ventilation, thus decreasing the potential morbidity associated with long-term oxygen supplement and assisted ventilation.

Characterization of benign hepatic tumors arising in fatty liver with SonoVue and pulse inversion US

BACKGROUND

We describe the spectrum of contrast-enhancement patterns of benign hepatic tumors arising in fatty liver on contrast-enhanced ultrasound (US).

METHODS

Sixteen patients (12 women and four men) with 27 benign hepatic tumors (17 hemangiomas, eight focal nodular hyperplasias, and two hepatocellular adenomas) arising in fatty liver underwent baseline and pulse inversion US after administration of SonoVue. Two experienced radiologists evaluated baseline echogenicity and dynamic enhancement pattern of each lesion in comparison with adjacent liver parenchyma.

RESULTS

After administration of SonoVue, in the arterial phase 13 of 17 hemangiomas showed peripheral globular enhancement and one showed a rim of peripheral enhancement, followed by progressive centripetal fill-in, which was complete in 10 of 14 cases and incomplete in four. Three of 18 hemangiomas showed rapid and complete fill-in in the arterial phase. Eight of eight focal nodular hyperplasias became hyperechoic in comparison with adjacent liver parenchyma in the arterial phase and slightly hyperechoic or isoechoic in the portal venous and delayed phases. Both adenomas showed strong arterial contrast enhancement that became less intense in the portal venous and delayed phases.

CONCLUSION

Contrast-enhanced US after administration of SonoVue enables depiction of typical contrast-enhancement patterns in most benign hepatic tumors arising in fatty liver, thus providing useful clues for characterization.

Invited review: Bovine milk fat globule membrane as a potential nutraceutical

For the last 15 yr, a great deal of knowledge has been accumulated on health beneficial factors, protein and nonprotein, of bovine milk fat globule membrane (MFGM). Among the health-beneficial components of the MFGM are cholesterolemia-lowering factor, inhibitors of cancer cell growth, vitamin binders, inhibitor of Helicobacter pylori, inhibitor of beta-glucuronidase of the intestinal Escherichia coli, xanthine oxidase as a bactericidal agent, butyrophilin as a possible suppressor of multiple sclerosis, and phospholipids as agents against colon cancer, gastrointestinal pathogens, Alzheimer's disease, depression, and stress. All of the above compel us to consider bovine MFGM as a potential nutraceutical.

Influence of dietary source of docosahexaenoic and arachidonic acids on their incorporation into membrane phospholipids of red blood cells in term infants

Here we studied whether the chemical structure of dietary arachidonic and docosahexaenoic acids in full-term infant diets affects their incorporation into erythrocyte membrane phospholipids. From birth to 3 months, infants were fed breast milk (n = 9) or formula milk containing arachidonic acid and docosahexaenoic acid provided by egg phospholipids (n = 10) or by low-eicosapentaenoic acid fish oil and fungal triglycerides (n = 10). We compared the fatty acid composition of erythrocyte phosphatidylethanolamine, phosphatidylcholine and sphingomyelin before and after administration of the experimental diet. At 3 months, infants on formula milk showed lower concentrations of docosahexaenoic acid (in phosphatidylcholine and in phosphatidylethanolamine) and arachidonic acid (in phosphatidylcholine) than those receiving breast milk. We conclude the incorporation of the two fatty acids into erythrocyte phospholipids depends mainly on the lipid composition of the diet received rather than the chemical form in which they are delivered.

Effects of Hyaluronan-Fortified Surfactant in Ventilated Premature Piglets with Respiratory Distress

We hypothesized that enriching surfactant with hyaluronan would restore lung function when tested in a premature animal model. Newborn piglets (85% gestation, term 112-114 days) were delivered by cesarean section, subjected to mechanical ventilation (tidal volume 6- 8 ml/kg) and randomly assigned to treatment with 50 or 100 mg/kg Curosurf (C50 and C100), 50 or 100 mg/kg Curosurf mixed with 2.5% HA (w/w, CH50 and CH100). A ventilated and not treated group (Cont) and a not treated and not ventilated group (Non) were included as controls. Six hours after treatment the lungs were removed and biochemical, biophysical, cytological and histological analyses were carried out. The CH100, CH50, C100 and C50 groups had variable but significantly improved alveolar phospholipid content, minimal surface tension, alveolar aeration and wet/dry lung weight ratios, but little histological evidence of lung injury. CH100, CH50 and C100 groups had the best effects in terms of oxygenation, lung compliance and histology and evidence of decreased inflammation (IL-8 and TNF-alpha mRNA expression). We conclude that HA added to 50 mg/kg Curosurf or use of 100 mg/kg Curosurf with or without HA provides the best effects in terms of lung function and reduction of inflammation.

Diagnostic efficacy of SonoVue®, a second generation contrast agent, in the assessment of extracranial carotid or peripheral arteries using colour and spectral Doppler ultrasound: a multicentre study

The purpose of this study was to demonstrate the improvement in diagnostic quality and diagnostic accuracy of SonoVue microbubble contrast-enhanced ultrasound (CE-US) versus unenhanced ultrasound imaging during the investigation of extracranial carotid or peripheral arteries. 82 patients with suspected extracranial carotid or peripheral arterial disease received four SonoVue doses (0.3 ml, 0.6 ml, 1.2 ml and 2.4 ml) with Doppler ultrasound performed before and following each dose. Diagnostic quality of the CE-US examinations was evaluated off-site for duration of clinically useful contrast enhancement, artefact effects and percentage of examinations converted from non-diagnostic to diagnostic. Accuracy, sensitivity and specificity were assessed as agreement of CE-US diagnosis evaluated by an independent panel of experts with reference standard modality. The median duration of clinically useful signal enhancement significantly increased with increasing SonoVue doses (p< or =0.002). At the dose of 2.4 ml of SonoVue, diagnostic quality evaluated as number of inconclusive examinations significantly improved, falling from 40.7% at baseline down to 5.1%. Furthermore, SonoVue significantly (p<0.01) increased the accuracy, sensitivity and specificity of assessment of disease compared with baseline ultrasound. SonoVue increases the diagnostic quality of Doppler images and improves the accuracy of both spectral and colour Doppler examinations of extracranial carotid or peripheral arterial disease.

Gray scale contrast enhancement and quantification in different positions of rabbit liver

OBJECTIVE

The purpose of this study was to evaluate the difference between central and ventral peripheral positions and the difference between left and right lobes in rabbit liver with gray scale contrast enhancement.

METHODS

An in vivo model of perfusion was studied with a sulfur hexafluoride contrast agent and low-mechanical-index, real-time, gray scale harmonic imaging. The contrast agent (0.1 mL/kg body weight) was applied respectively in 10 rabbits by intravenous bolus injection. The time-intensity curve was used to obtain flow-related parameters such as time to enhancement (ET), time to peak intensity (PIT), peak signal intensity (PSI), enhancement duration (ED), and area under the curve (AUC).

RESULTS

There was a significant difference in parameters of the time-intensity curve between central and peripheral ventral positions of liver parenchyma (P < .05), except for the ED in the left liver. The ET and PIT were earlier, the PSI higher, the ED longer, and the AUC larger in the central position of parenchyma than in the peripheral position. In addition, the ET and PIT were earlier, the PSI higher, the ED longer, and the AUC larger in the right lobe of liver parenchyma than in the left lobe. There was a significant difference in parameters of the time-intensity curve between the left and right lobes of liver parenchyma (P < .05), except for the ET of the peripheral position.

CONCLUSIONS

Flow parameters are different between central and ventral peripheral positions and between left and right lobes of hepatic parenchyma.

Bronchoalveolar Lavage with Diluted Porcine Surfactant in Mechanically Ventilated Term Infants with Meconium Aspiration Syndrome

BACKGROUND

To evaluate the efficacy and safety of bronchoalveolar lavage (BAL) with diluted porcine surfactant in mechanically ventilated term infants with severe acute respiratory distress syndrome (ARDS) due to meconium aspiration syndrome (MAS).

METHODS

Eight consecutive mechanically ventilated term infants with severe ARDS due to MAS underwent BAL with 15 mL/kg of diluted (5.3mg phospholipid/mL) surfactant saline suspension (porcine surfactant [Curosurf]). Treatment was administered slowly in aliquots of 2.5 mL. The mean age of neonates at treatment was 3.5 (range 1-8) hours. Heart rate, systemic blood pressure and oxygen saturation were monitored continuously. Arterial blood gases were measured immediately before treatment, and again at 3 and 6 hours post-treatment. Chest x-rays were taken 6 and 24 hours after treatment.

RESULTS

Radiological improvement was evident in all eight patients 6 hours post-treatment. Compared with pre-BAL values, significant improvements (p < 0.05) in mean values for partial pressure of oxygen in arterial blood, partial pressure of carbon dioxide in arterial blood, pH, arterial/alveolar O2 ratio and oxygenation index were documented at 3 and 6 hours after BAL. In all patients, tracheal fluids that had been meconium-stained prior to BAL were clear of meconium after BAL. Only one patient required nitric oxide therapy for transient pulmonary hypertension. No adverse sequelae of treatment occurred during the study.

CONCLUSIONS

BAL with dilute porcine surfactant administered slowly in 2.5 mL aliquots improved oxygenation and chest x-ray findings, without causing major adverse effects, in mechanically ventilated term infants with ARDS due to MAS.

Real-time contrast-enhanced specific ultrasound in staging and follow-up of splenic lymphomas

From January 2003 to April 2005 we studied 25 lymphoma patients (10 with HD, 4 with low-grade NHL, 6 with high-grade NHL and 5 with chronic lymphatic leukaemia; 14 men, 11 women, age range 28-79 years). After a baseline US study we rapidly injected 4.8 mL of the second-generation microbubble contrast agent SonoVue (Bracco, Italy). Contrast enhanced studies were carried out with the contrast-specific software named Contrast Tuned Imaging (Esaote, Italy) using a continuous, harmonic acquisition and a low acoustic pressure. The CS-US findings were correlated with results of standard tools, including CT, MRI, US follow up. CS-US revealed correctly 47 out of the 52 lesions identified by CT scan, in the absence of false positive findings (sensitivity = 90%; Specificity = 100%, in comparison to CT scan). Complete concordance in evaluating the lesion extension of the CS-US in respect to CT was 88%, while underestimate occurred in 9% and overestimate in 3% of cases. On the contrary, basic sonography defined correctly the dimensional alteration in 52% of the cases, underestimated in 35% and overestimated in 13%, thus showing significantly lower accuracy (chi-square = 30.0, p < 0.001). In our experience, CS-US was superior to conventional sonography even from a qualitative point of view.

[The influence of phospholipids food and antioxidant at patients with hypertension]

It was investigated the influence of dietary therapy by adding phospholipids (5 gr/daily lecithin) and antioxidant agents (90 mg/daily coenzyme Q10) on clinical and biochemical parameters at patients with hypertension I and II stages. At the end of the 4-week period, decreased systolic and diastolic blood pressure, level of the total cholesterol, lipoprotein low density (LDL) and apolipoprotein A1 in their plasma.

Phospholipid nanosomes

Phospholipid nanosomes are small, uniform liposomes manufactured utilizing supercritical fluid technologies. Supercritical fluids are first used to solvate phospholipid raw materials, and then decompressed to form phospholipid nanosomes that can encapsulate hydrophilic molecules such as proteins and nucleic acids. Hydrophobic therapeutics are co-solvated with phospholipid raw materials in supercritical fluids that, when decompressed, form phospholipid nanosomes encapsulating these drugs in their lipid bilayers. Mathematical modeling and semi-empirical experiments indicate that the size and character of phospholipid nanosomes depend on the several process parameters and material properties including the size and design of decompression nozzle, bubble size, pressure and the rate of decompression, interfacial forces, charge distribution and the nature of compound being encapsulated. Examples are presented for the encapsulation of a protein and hydrophobic drugs. In vitro and in vivo data on breast cancer cells and xenografts in nude mice indicate that paclitaxel nanosomes are less toxic and much more effective than paclitaxel in Cremophor EL (Taxol). Camptothecin nanosomes demonstrate that the normally very water-insoluble camptothecin can be formulated in a biocompatible aqueous medium while retaining in vivo efficacy against lymphoma xenografts in nude mice. In vitro data for betulinic acid nanosomes demonstrate enhanced efficacy against HIV-1 (EC50 of 1.01 microg/ml versus 6.72 microg/ml for neat betulinic acid). Phospholipid nanosomes may find utility in the enhanced delivery of hydrophilic drugs such as recombinant proteins and nucleic acid as well as hydrophobic anticancer and anti-HIV drugs.

Adhesion prevention comparing liquid and solid barriers in the rabbit uterine horn model

OBJECTIVE

The purpose of this study was to assess the ability of four different either solid or fluid barriers to reduce adhesions in an established model of gynecological surgery.

STUDY DESIGN

50 Chinchilla rabbits underwent bilateral deperitonealization and devascularization of the uterine horns (DUH). Afterwards solid membranes of either hyaluronic acid-carboxymethylcellulose (HA-CMC) or lactide-caprolactone-copolymer (LCC) were placed around the injured uterine horns or fluids (icodextrin (ID) or phospholipids (PL)) were intraperitonealy administered. The control group went without protection. After 10 days, adhesions were measured by planimetry.

RESULTS

Phospholipids (median 49.8 mm2) significantly reduced adhesion areas in comparison to all other groups: surgical controls (median 230.6 mm2), HA-CMC (median 194.9 mm2), LCC (median 327.1 mm2), and icodextrin (median 242.1 mm2).

CONCLUSIONS

These results prove the efficacy of phospholipids to reduce primary adhesion formation in the Chinchilla double uterine horn model compared to HA-CMC, LCC and icodextrin. Future clinical studies are recommended.