A prostacyclin analogue, iloprost, protects from bleomycin-induced pulmonary fibrosis in mice

<p>Abstract</p> <p>Background</p> <p>Metabolites of arachidonic acid such as prostacyclin (PGI₂) have been shown to participate in the pathogenesis of pulmonary fibrosis by inhibiting the expression of pro-inflammatory and pro-fibrotic mediators. In this investigation, we examined whether iloprost, a stable PGI₂analogue, could prevent bleomycin-induced pulmonary inflammation and fibrosis in a mouse model.</p> <p>Methods</p> <p>Mice received a single intratracheal injection of bleomycin with or without intraperitoneal iloprost. Pulmonary inflammation and fibrosis were analysed by histological evaluation, cellular composition of bronchoalveolar lavage (BAL) fluid, and hydroxyproline content. Lung mechanics were measured. We also analysed the expression of inflammatory mediators in BAL fluid and lung tissue.</p> <p>Results</p> <p>Administration of iloprost significantly improved survival rate and reduced weight loss in the mice induced by bleomycin. The severe inflammatory response and fibrotic changes were significantly attenuated in the mice treated with iloprost as shown by reduction in infiltration of inflammatory cells into the airways and pulmonary parenchyma, diminution in interstitial collagen deposition, and lung hydroxyproline content. Iloprost significantly improved lung static compliance and tissue elastance. It increased the expression of IFNγ and CXCL10 in lung tissue measured by RT-PCR and their levels in BAL fluid as measured by ELISA. Levels of TNFα, IL-6 and TGFβ1 were lowered by iloprost.</p> <p>Conclusions</p> <p>Iloprost prevents bleomycin-induced pulmonary fibrosis, possibly by upregulating antifibrotic mediators (IFNγ and CXCL10) and downregulating pro-inflammatory and pro-fibrotic cytokines (TNFα, IL-6, and TGFβ1). Prostacyclin may represent a novel pharmacological agent for treating pulmonary fibrotic diseases.</p

Impaired lipid metabolism in idiopathic pulmonary alveolar proteinosis

<p>Abstract</p> <p>Background</p> <p>It is well known that lipids abnormally accumulate in the alveoli during idiopathic pulmonary alveolar proteinosis (PAP). It is unclear, however, whether lipids also abnormally accumulate in serum. This study investigated the serum lipid panels in idiopathic PAP patients and explored the relationships between serum levels and the severity of idiopathic PAP.</p> <p>Methods and Results</p> <p>Clinical data including the level of serum lipids were evaluated in 33 non-diabetic idiopathic PAP patients and 157 healthy volunteers. Serum levels of triglyceride were higher in PAP patients than in healthy subjects (median: 192.00 mg/dl (<it>P</it>₂₅: 104.36, <it>P</it>₇₅: 219.00) <it>vs </it>119.56 mg/dl (<it>P</it>₂₅: 78.81, <it>P</it>₇₅: 193.03), <it>P </it>< 0.05), while high-density lipoprotein cholesterol (HDL-C) levels were lower in patients than in the control group (42.50 ± 10.30 <it>vs </it>51.34 ± 12.06 mg/dl, <it>P </it>< 0.01). Forced expiratory volume in one second and forced vital capacity in hypertriglyceridemia patients were lower than those in patients with normal triglyceride. Serum LDL-C and HDL-C ratio correlated negatively with PaO₂(r = -0.403, <it>P </it>< 0.05) and positively with lactate dehydrogenase (r = 0.381, <it>P </it>< 0.05).</p> <p>Conclusions</p> <p>PAP associates with high triglyceride and low HDL levels in the serum, and these lipids provide potential intervention strategy for treatment.</p

Molecular Epidemiology of Clinical Isolates of Carbapenem-Resistant Acinetobacter spp. from Chinese Hospitals▿

Carbapenem resistance in Acinetobacter spp. is an emerging problem in China. We investigated the molecular epidemiology and carbapenemase genes of 221 nonrepetitive imipenem-resistant clinical isolates of Acinetobacter spp. collected from 1999 to 2005 at 11 teaching hospitals in China. Genotyping by pulsed-field gel electrophoresis (PFGE) found 15 PFGE patterns. Of these, one (clone P) was identified at four hospitals in Beijing and another (clone A) at four geographically disparate cities. Most imipenem-resistant isolates exhibited high-level resistance to all β-lactams and were only susceptible to colistin. blaOXA-23-like genes were found in 97.7% of isolates. Sequencing performed on 60 representative isolates confirmed the presence of the blaOXA-23 carbapenemase gene. Analysis of the genetic context of blaOXA-23 showed the presence of ISAba1 upstream of blaOXA-23. All of the 187 A. baumannii isolates identified by amplified RNA gene restriction analysis carried a blaOXA-51-like oxacillinase gene, while this gene was absent from isolates of other species. Sequencing indicated the presence of blaOXA-66 for 18 representative isolates. Seven isolates of one clone (clone T) carried the plasmid-mediated blaOXA-58 carbapenemase gene, while one isolate of another clone (clone L) carried the blaOXA-72 carbapenemase gene. Only 1 isolate of clone Q carried the blaIMP-8 metallo-β-lactamase gene, located in a class 1 integron. Of 221 isolates, 77.8% carried blaPER-1-like genes. Eleven different structures of class 1 integrons were detected, and most integrons carried genes mediating resistance to aminoglycosides, rifampin, and chloramphenicol. These findings indicated clonal spread of imipenem-resistant Acinetobacter spp. and wide dissemination of the OXA-23 carbapenemase in China