Certolizumab pegol for the treatment of psoriasis.

INTRODUCTION: Psoriasis is a chronic immunomediated and inflammatory disease involving mainly skin and joints, often associated with several metabolic and non-metabolic comorbidities. TNF-alpha inhibitors have shown long-term efficacy and safety/tolerability in psoriasis, and preliminary data support the use of certolizumab pegol (CZP) as well. Areas covered: The authors review the pharmacological properties of CZP, as well as its safety data and efficacy profile. They also review the quality of life outcomes related to CZP in psoriasis. The authors also provide their expert opinion on the subject. Expert opinion: CZP is a promising treatment for psoriasis owing to its rapid reduction of disease activity, long-term therapeutic efficacy - both in bio-naive and non-bio-naive patients, long term safety and low rate of site injection reactions. CZP seems to be a promising therapeutic option for psoriasis patients, although further evidence supporting the continuing clinical program for development of CZP in psoriasis is needed.

Collagen loss and impaired wound healing is associated with c-Myb deficiency.

Collagen type I serves as an abundant structural and signalling component of skin. It is also an established target gene of the transcription factor, c-Myb. When c-myb-/- embryos were examined it was observed that their skin was markedly thinner than normal. Importantly, immunohistochemical investigation showed complete absence of collagen type I. Although these homozygous knock-out embryos fail to develop beyond day 15, fibroblasts established from these embryos (mouse embryonic fibroblasts [MEFs]) show defective proliferative responses. Furthermore, in vitro scratch wound assays demonstrated that these c-myb-/- MEFs also exhibit slower closure than their wild-type counterparts. Embryonic lethality has meant that examination of the role of c-Myb in adult mouse skin has not been reported to date. However, in view of the abundance of collagen type I in normal skin, its role in skin integrity and the in vitro data showing proliferative and migration defects in c-myb-/- MEFs, we investigated the consequences of heterozygous c-myb loss in adult mice on the complex process of skin repair in response to injury. Our studies clearly demonstrate that heterozygous c-myb deficiency has a functional effect on wound repair, collagen type I levels and, in response to wounding, transforming growth factor-beta1 (an important collagen stimulating factor) induction expression is aberrantly high. Manipulation of c-Myb may therefore provide new therapeutic opportunities for improving wound repair while uncontrolled expression may underpin some fibrotic disorders.

Identification of a novel human DRB1*13 allele by sequence-based DRB typing.

Herein, we report on a novel DRB1 allele (DRB1*1368) identified during sequence-based HLA-DRB typing. This new DRB1 allele is identical to DRB1*1301 at exon 2 except for a single-nucleotide substitution at codon 37, changing the amino acid Asn to Asp.

Scleroderma fibroblasts constitutively express the long pentraxin PTX3.

OBJECTIVE: PTX3 is a secreted molecule which consists of a C-terminal domain similar to classical pentraxins (e.g. C-reactive protein) and of an unrelated N-terminal domain. Unlike the classical pentraxins, PTX3 is expressed in response to IL-1beta and TNF-alpha but not to IL-6. The present study was designed to investigate the expression of PTX3 in normal and scleroderma fibroblasts. METHODS: Normal and SSc fibroblasts were cultured in the presence and absence of inflammatory cytokines. PTX3 mRNA expression in fibroblasts was evaluated by Northern analysis. PTX3 protein levels in fibroblast culture medium were estimated by ELISA. RESULTS: Normal fibroblasts were induced to express high levels of P7X3 mRNA by IL-1beta and TNF-alpha but not by other cytokines or growth factors. Scleroderma fibroblasts, unlike normal fibroblasts, constitutively expressed high levels of PTX3 in the absence of deliberate stimulation. The constitutive expression of PTX3 in SSc fibroblasts was not modified by anti-TNF-alpha antibodies or IL-1 receptor antagonist. In contrast, IFN-gamma and TGF-beta inhibited the constitutive but not the stimulated expression of PTX3 in SSc fibroblasts. CONCLUSIONS: PTX3 is a main feature of activated scleroderma fibroblasts.

A new HLA-DRB1*11 allele, DRB1*1144, identified by cloning and sequencing.

We report here the identification of a novel DRB1*11 allele, DRB1*1144, identified during sequence-based HLA-DRB1 typing. Molecular cloning and direct sequencing confirmed that the new allele is identical to DRB1*110401 at exon 2, except for a single nucleotide substitution (GTG-->GCG) changing codon 38 from Valine to Alanine.

Oxidative stress in scleroderma: maintenance of scleroderma fibroblast phenotype by the constitutive up-regulation of reactive oxygen species generation through the NADPH oxidase complex pathway.

OBJECTIVE: To explore the role of reactive oxygen species (ROS) in the in vitro activation of skin fibroblasts from patients with systemic sclerosis (SSc). METHODS: Fibroblasts were obtained from involved skin of patients with limited or diffuse SSc. Oxidative activity imaging in living cells was carried out using confocal microscopy. Levels of O2- and H2O2 released from fibroblasts were estimated by the superoxide dismutase (SOD)-inhibitable cytochrome c reduction and homovanilic acid assays, respectively. To verify NADPH oxidase activation, the light membrane of fibroblasts was immunoblotted with an anti-p47phox-specific antibody. Fibroblasts were stimulated with various cytokines and growth factors to determine whether any of these factors modulate ROS generation. Cell proliferation was estimated by 3H-thymidine incorporation. Northern blot analysis was used to study alpha1 and alpha2 type I collagen gene expression. RESULTS: Unstimulated skin fibroblasts from SSc patients released more O2- and H2O2 in vitro through the NADPH oxidase complex pathway than did normal fibroblasts, since incubation of SSc fibroblasts with diphenylene iodonium, a flavoprotein inhibitor, suppressed the generation of ROS. This suppression was not seen with rotenone, a mitochondrial oxidase inhibitor, or allopurinol, a xanthine oxidase inhibitor. Furthermore, the cytosolic component of NADPH oxidase, p47phox, was translocated to the plasma membrane of resting SSc fibroblasts. A transient increase in ROS production was induced in normal but not in SSc fibroblasts by interleukin-1beta (IL-1beta), platelet-derived growth factor type BB (PDGF-BB), transforming growth factor beta1 (TGFbeta1), and H2O2. Treatment of normal and SSc fibroblasts with tumor necrosis factor a (TNFalpha), IL-2, IL-4, IL-6, IL-10, interferon-alpha (IFNalpha), IFNgamma, granulocyte-macrophage colony-stimulating factor (GM-CSP), G-CSF, or connective tissue growth factor (CTGF) had no effect on ROS generation. Constitutive ROS production by SSc fibroblasts was not inhibited when these cells were treated with catalase, SOD, IL-1 receptor antagonist, or antibodies blocking the effect of TGFbeta1, PDGF-BB, and other agonists (IL-4, IL-6, TNFalpha, CTGF). In contrast, treatment of SSc fibroblasts with the membrane-permeant antioxidant N-acetyl-L-cysteine inhibited ROS production, and this was accompanied by decreased proliferation of these cells and down-regulation of alpha1(I) and alpha2(I) collagen messenger RNA. CONCLUSION: The constitutive intracellular production of ROS by SSc fibroblasts derives from the activation of an NADPH oxidase-like system and is essential to fibroblast proliferation and expression of type I collagen genes in SSc cells. Our results also exclude O2-, H2O2, IL-1beta, TGFbeta1, PDGF-BB, IL-4, IL-6, TNFalpha, or CTGF as mediators of a positive, autocrine feedback mechanism of ROS generation.

Studies of bone density, quantitative ultrasound, and vertebral fractures in relation to collagen type I alpha 1 alleles in elderly women.

Previous studies have demonstrated that an Sp1 binding site polymorphism in the collagen type I gene (COLIA1) is related to reduced bone mineral density (BMD) and osteoporotic fractures in certain populations, particularly in the elderly. We have examined the relationship among these COLIA1 Sp1 alleles, BMD, quantitative ultrasound properties of bone, and fractures in a population-based cohort of elderly women from the UK. The study group comprised 314 women aged 75 years and over who agreed to participate in a clinical study of bisphosphonate therapy in preventing bone loss at the hip. Women were enrolled regardless of the presence or absence of osteoporosis, but those with other diseases that might affect skeletal metabolism were excluded. The genotype distribution for the Sp1 polymorphism was in Hardy-Weinberg equilibrium (SS - 78%; Ss - 20%; ss - 2%) but the proportion of individuals who carried the "s" allele (22%) was significantly lower than previously observed in another study of the UK population (37.1%) (P < 0.001). There were no significant associations between COLIA1 genotypes and metacarpal cortical index, BMD of the forearm, tibial SOS, calcaneal SOS, or calcaneal BUA. While there was a trend towards lower BMD values at the hip in patients with Ss and ss genotypes, this was not statistically significant (SS = 0.721 +/- 0.14; Ss = 0.704 +/- 0.13; ss = 0.683 +/- 0.20 P = 0.6). Prevalent vertebral fractures occurred in 22% of subjects and prior fractures of the wrist, ankle, and hip were reported by 20%, but there was no significant difference in COLIA1 genotype distribution between fracture patients and controls. We conclude that COLIA1 Sp1 alleles are not significantly associated with BMD, ultrasound properties of bone, or fractures in this population-based sample of elderly women.

A prospective randomized double-blinded controlled study of ropivacaine 0.75% versus bupivacaine 0.5%-mepivacaine 2% for peribulbar anesthesia.

BACKGROUND AND OBJECTIVES: Ropivacaine 1% has recently been used in clinical trials for peribulbar anesthesia. This study aims to compare the safety and the efficacy of ropivacaine 0.75% with that of a 1:1 mixture of bupivacaine 0.5% and mepivacaine 2% for peribulbar anesthesia. METHODS: Two thousand patients undergoing peribulbar anesthesia for elective cataract phacoemulsification were prospectively studied over a 1-year period and randomly assigned to 1 of 2 groups according to the local anesthetic used. One thousand patients were administered peribulbar anesthesia with 9 mL of ropivacaine 0.75% plus 1 mL of hyaluronidase (group R), and 1,000 patients received peribulbar anesthesia with 4 mL of bupivacaine 0.5% plus 4 mL of mepivacaine 2% plus 1 mL of hyaluronidase plus 1 mL of sodium bicarbonate (group BM). Peribulbar anesthesia was always accomplished by the same physician by 2 injections of 5 mL each, with a 25-gauge 25-mm needle. Evaluation was performed by another physician blinded to the technique used and included assessment of pain on local anesthetic injection, ocular and eyelid akinesia, need for top-up injections, onset time and duration of anesthesia, intraoperative analgesia, duration of surgery, hemodynamic parameters, and incidence of perioperative complications. RESULTS: A greater incidence of pain on injection was found in group BM (P<.001). No difference between the groups was found regarding the onset time and the duration of anesthesia. Perioperative analgesia was satisfactory in both groups with no significant difference. Patients in group R showed a reduced need for top-up injection and a better ocular akinesia at 8 and 10 minutes (P<.01). The akinesia of the eyelid was comparable in the 2 groups and complete in all cases at 8 minutes. Cardiac arrhythmias were more frequent in group BM (P<.01). Local complications did not differ between the groups. An increase in mean artierial blood pressure and heart rate was observed in both groups 1 minute after injection of local anesthetic. CONCLUSIONS: Peribulbar anesthesia with ropivacaine provided better ocular akinesia 8 to 10 minutes after block insertion than a bupivacaine-mepivacaine mixture, which reduced the need for top-up injections. Ropivacaine also caused less pain on injection.

Expression and production of the long pentraxin PTX3 in rheumatoid arthritis (RA).

PTX3 is a secreted molecule which consists of a C-terminal domain similar to classical pentraxins (e.g. C-reactive protein (CRP)) and of an unrelated N-terminal domain. Unlike the classical pentraxins, the long pentraxin PTX3 is expressed in response to IL-1beta and tumour necrosis factor-alpha (TNF-alpha), but not to IL-6, in various cell types. The present study was designed to investigate the expression of PTX3 in RA. Dissociated RA and osteoarthritis (OA) type B synoviocytes were cultured in the presence and in the absence of inflammatory cytokines. PTX3 mRNA expression in synoviocytes was evaluated by Northern analysis. PTX3 protein levels in synovial cell cultures and synovial fluid were estimated by ELISA, and PTX3 distribution in synovial tissues by immunohistochemical techniques. OA synoviocytes were induced to express high levels of PTX3 mRNA by TNF-alpha, but not by other cytokines including IL-1beta and IL-6. RA synoviocytes, unlike OA synoviocytes, constitutively expressed high levels of PTX3 in the absence of deliberate stimulation. The constitutive expression of PTX3 in RA synoviocytes was not modified by anti-TNF-alpha antibodies, IL-1 receptor antagonist or a combination of the two agents. In contrast, interferon-gamma and transforming growth factor-beta inhibited PTX3 constitutive expression in RA synoviocytes. The joint fluid from RA patients contained higher levels of immunoreactive PTX3 than controls and the synovial tissue contained endothelial cells and synoviocytes positive for PTX3 by immunohistochemistry. In conclusion, PTX3 may play a role in inflammatory circuits of RA, and its relevance as a marker of disease activity deserves further study.

Reduction of bcl-2 in T cells during immunosuppressive therapy in patients with severe juvenile onset systemic lupus erythematosus.

Overexpression of bcl-2 protein has been observed in the cytoplasm of T lymphocytes from adults with systemic lupus erythematosus (SLE). The aims of our study were to investigate the distribution of bcl-2 in T and B cells from patients affected with juvenile onset SLE (JSLE) and to monitor the modification of bcl-2 expression under immunosuppressive therapy. Thirty-two JSLE patients entered the study; 45 pathological and 16 healthy subjects were studied as controls. In SLE patients the disease activity was assessed using SLE disease activity index score. Bcl-2 expression was evaluated by cytofluorimetry. PCR analysis of t(14,18) translocation was performed from genomic DNA isolated from peripheral blood mononuclear cells. An increased bcl-2 expression both on cytoplasm and on cell surface of circulating T lymphocytes in JSLE patients with active disease was found. A variation, under pharmacological treatment, of protein expression during the course of the disease was observed. PCR analyses demonstrated that 14, 18 translocation was not associated with bcl-2 overexpression. Our data show a strong correlation between bcl-2 protein expression and disease activity and suggest an alteration of apoptotic regulation in JSLE patients.

Natural surfactant supplementation in ARDS in paediatric age.

OBJECTIVE: To evaluate the effects of natural surfactant supplementation in infants, children and adolescents affected by ARDS from different origins in order to reduce lung barotrauma due to artificial ventilation, improve gas exchange, reduce oxygen toxicity and survival. MATERIALS AND METHODS: Two groups, the first consisting of 22 children, 7 days-24 months, and the second of 8 oncohaematologic patients, 2-16 years, affected by ARDS from sepsis, inhalation syndrome and interstitial pneumonia, candidates for ECMO, were treated intratracheally with 50 mg/kg of natural surfactant. Before treatment all patients had been mechanically ventilated using PEEP levels > or = 8 cm H2O and FiO2 > or = 0.6, for at least 24 hours without any improvement in gas exchange. RESULTS: From 15 mins after surfactant administration a progressive improvement in PaO2 was noted which peaked at 3 hours. In two cases in the first group a worsening in PaO2 occurred starting from 12-18 hours, which needed additional doses. All patients in the second group needed additional doses after 12 h. No significant PaCO2 variations were noted until 24 hours. In all cases the chest X-ray improved at 4 hours and clearing was obtained starting from 24 hours in those cases where an additional dose had not been necessary. Computed Tomography confirmed the improvement in lung pathology. All the children in the first group survived except one HIV-positive child. The oncohaematologic children showed an improvement in PaO2 after each administration of surfactant even though they later died due to their initial disease, except one child. COMMENT: Surfactant efficacy in this study appears to depend on the severity of lung pathology and to be strictly connected with early treatment.

Expression of c-myb and B-myb oncogenes on myelofibrotic marrow fibroblasts.

The term IMF (Idiopathic Myelofibrosis) refers to a primary bone marrow disease in which the normal haematopoietic bone marrow cells are for unknown reasons replaced by connective tissue. The pathogenesis of the disease has not been clarified yet. We have speculated that the increment of proliferation of bone marrow fibroblasts in IMF may be the consequence of the over-expression of some oncogenes, leading or contributing to the fibrosis via a cell amplification. Thus, we investigated the possible role of the c-myb and B-myb genes in IMF and control bone marrow fibroblasts in different culture conditions to evaluate proliferation parameters in the absence or presence of serum. Using the reverse transcriptase polymerase chain reaction technique, we demonstrated that the kinetics of induction was similar for both c-myb and B-myb during the proliferation of normal bone marrow fibroblasts. When compared to normal controls, cultured IMF fibroblasts showed more elevated values of c-myb and B-myb RNA; furthermore, after a 72 hours stimulation with serum, c-myb and B-myb messages remained relatively high in myelofibrotic fibroblasts. Finally, after serum starvation, c-myb and to a lesser extent B-myb RNA levels remained unusually high in IMF fibroblasts, while under the same experimental conditions c-myb and B-myb messages became virtually undetectable in normal bone marrow fibroblasts. To our knowledge this work represents the first description of an abnormal behavior of these genes in IMF fibroblasts.

C-myb, but not B-myb, upregulates type I collagen gene expression in human fibroblasts.

C-myb and B-myb belong to the myb family of transcription factors. We have shown previously that c-myb is deregulated in fibroblasts from systemic sclerosis (scleroderma) patients relative to normal fibroblasts. Scleroderma fibroblasts are known to express elevated levels of collagen genes and transforming growth factor beta is known to be a pro-fibrotic cytokine and to induce transcription of type I collagen genes. We have therefore investigated the role of c-myb and B-myb in the regulation of type I collagen genes in response to transforming growth factor beta in normal human fibroblasts. We show that, in these cells, transforming growth factor beta treatment induces c-myb as well as collagen alpha1(I) and alpha2(I) gene expression, but not B-myb. Furthermore we demonstrate by cotransfection assays that c-myb can upregulate alpha1(I) and alpha2(I) collagen promoters by 6-10-fold whereas B-myb is inactive. The activity of c-myb on both type I collagen promoters requires a functional c-myb DNA binding domain suggesting a direct interaction between c-myb and these promoters. Indeed c-myb is active also on a 500 bp fragment of the alpha2(I) collagen promoter and can bind to this fragment in electrophoretic mobility shift assays. Finally, we show that anti-c-myb anti-sense treatment reduces alpha1(I) and to a lesser extent alpha2(I) collagen gene expression. These data strongly suggest that c-myb, but not B-myb, plays a direct role in the upregulation of type I collagen gene expression in response to transforming growth factor beta.

Monocytes of patients wiht systemic sclerosis (scleroderma spontaneously release in vitro increased amounts of superoxide anion.

It has been suggested that toxic oxygen free radicals can be involved in the pathogenesis of systemic sclerosis (scleroderma) (SSc). Because the cells that contribute to the generation of free radicals are not known, our aim was (i) to evaluate the ability of unmanipulated and phorbol 12-myristate 13-acetate-stimulated monocytes and polymorphonucleate neutrophils of SSc patients to generate superoxide anion (O2*-); and (ii) to investigate whether the O2*- produced by these cells involved the activation of nicotinamide-adenine dinucleotide diphosphate oxidase biochemical pathway. Employing the superoxide dismutase-inhibitable reduction of cytochrome c to evaluate the generation of O2*-, unmanipulated monocytes of SSc patients generated more O2*- than primary Raynaud's phenomenon patients and normal control monocytes (p = 0.0001), and the release was higher in patients with diffuse cutaneous involvement and 5 y or less disease duration (p = 0.02). The involvement of nicotinamide-adenine dinucleotide diphosphate oxidase in the enhanced 02*- production was demonstrated by the finding that the cytosolic components of the enzyme, p47phox and p67phox, were both translocated to the plasma membrane of enriched but otherwise unmanipulated monocytes of SSc patients. The involvement of mitochondrial oxidases was excluded by the lack of inhibition of O2*- production when monocytes were incubated in the presence of rotenone, a mitochondrial oxidase inhibitor. Upon stimulation with phorbol 12-myristate 13-acetate, monocytes of SSc patients produced more O2*- than controls. In SSc patients untreated polymorphonucleate neutrophils generated significantly less O2*- than monocytes (p = 0.0001) and only slightly more than polymorphonucleate neutrophils of primary Raynaud's phenomenon patients and normal controls (p = 0.03). In conclusion, we demonstrate that in patients with scleroderma, unmanipulated and phorbol 12-myristate 13-acetate-stimulated monocytes release in vitro increased amounts of superoxide anion through the activation of nicotinamide-adenine dinucleotide diphosphate oxidase and, thus, contribute to the oxidative stress found in this disease.

Evaluation of the efficiency of heat and moisture exchangers during paediatric anaesthesia.

This study evaluates the efficiency of heat and moisture exchangers (HMEs) in allowing adequate humidification and warming during anaesthesia in children. Eighteen paediatric patients undergoing anaesthesia were divided into two groups: group A ten patients: infants up to 10 kg-->Hygrobaby HME; group B 8 patients: children above 10 kg-->Hygroboy HME. The following parameters were evaluated: body temperature (bT), room temperature (rT), fresh gas temperature, HME warm-up time, inspired and expired gases temperature and humidity, conserving efficiency, and duration of anaesthesia. Gas temperatures were recorded by means of a recorder fitted with four thermal probes. Humidity values were mathematically derived. The correlation between efficiency and rT, bT, and fresh gas temperature was computed. In both groups the inspired gases temperatures were below 30 degrees C. Inspired absolute humidity was never more than 28 mgH2O.l(-1). The conserving efficiency was good (0.93 in both groups). A positive correlation was found between efficiency and fresh gas temperature. HMEs did not meet the minimum standards for humidity and heating during anaesthesia in children, although their conserving efficiency was found to be satisfactory.

Porcine-derived surfactant treatment of severe bronchiolitis.

BACKGROUND: It is hypothesized that surfactant treatment helps to improve severe bronchiolitis by restoring surfactant system activity. This study aims to assess the effect of surfactant on gas exchange, peak inspiratory pressure and duration of mechanical ventilation and intensive care unit (ICU) stay in children with severe bronchiolitis. METHODS: Twenty children with bronchiolitis requiring mechanical ventilation were randomly assigned to one of two groups (10 patients each). Group A was treated with continuous positive pressure ventilation (CPPV) plus surfactant. Group B was treated with CPPV only. Porcine-derived surfactant, 50 mg/kg body weight, was instilled into the trachea. Arterial tension of oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio, arterial tension of carbon dioxide (PaCO2), and peak inspiratory pressure (PIP) were assessed. Heart rate and non-invasive arterial blood pressure were monitored. The duration of CPPV and the length of ICU stay were also recorded. Finally, the incidence of complications and the survival rate were assessed. RESULTS: In group A, the PaO2/FiO2 ratio significantly improved from 1 h and a reduction in PaCO2 was noted from 12 h. A reduction of PIP was observed from 3 h. The duration of CPPV and the length of ICU stay were reduced in group A. No complications were reported in either group and all children survived. CONCLUSIONS: Surfactant treatment of severe bronchiolitis appeared to improve gas exchange, reduce PIP and shorten CPPV and ICU stay. However, these initial results must be confirmed by a larger and more rigorously controlled study.

Perfluorocarbon broncho-alveolar lavage and liquid ventilation versus saline broncho-alveolar lavage in adult guinea pig experimental model of meconium inhalation.

OBJECTIVE: This study compares perfluorocarbon broncho-alveolar lavage (PFC-BAL) with isotonic saline broncho-alveolar lavage (saline-BAL) in an experimental model of meconium aspiration in adult guinea pigs. DESIGN: Prospective controlled experimental study. PATIENTS AND METHODS: Ten male guinea pigs were given 1 ml of human meconium, diluted to 10% in isotonic saline, via tracheostomy and then artificially ventilated. After stabilization, five animals (control group) underwent BAL with 10 ml/ kg isotonic saline solution. After bronchial suctioning, a further BAL with 2 ml/kg saline was performed. The other five animals (study group) underwent BAL with 100 ml/kg of PFC (RIMAR 101). Bronchosuction was effected at 5 min and then a BAL with PFC 2 ml/kg was performed. Both groups received conventional mechanical ventilation during the lavage procedures. Within 20 min all the saline-BAL treated animals died, whereas the PFC-BAL treated animals survived and were then treated with total liquid ventilation (TLV) by gravity. MEASUREMENTS AND RESULTS: After meconium inhalation in both groups, a large alveolar-arterial oxygen difference, hypercarbia, severe acidosis and tachycardia were noticed. In PFC treated animals, an improvement in blood gases was noted and acid-base balance remained stable compared to saline-BAL treated animals. No haemodynamic change was observed during or after PFC-BAL, while during saline-BAL there was evidence of bradycardia, hypotension and respiratory failure, which led to the death of the animals. The histological lung sections in the PFC-BAL group showed evidence of normal alveolar expansion with a minimal presence of meconium debris in the small bronchioles. In saline-BAL treated animals, the lung structure appeared severely compromised with the presence of meconium in bronchioles and alveoli, intra-alveolar oedema and haemorrhagic areas. CONCLUSIONS: This study confirms the detrimental effects of meconium aspiration and the impairment of lung function following saline-BAL. By contrast, PFC-BAL and TLV by gravity seemed to prevent absorption of meconium, facilitate its removal, improve gas exchange and reduce lung barotrauma.