Impaired alveolarization and intra-uterine growth restriction in rats: a postnatal genome-wide analysis.

Intra-uterine growth restriction (IUGR) dramatically increases the risk of bronchopulmonary dysplasia in preterm babies, a disease characterized by arrested alveolarization and abnormal microvascular angiogenesis. We have previously described a rodent low protein diet (LPD) model of IUGR inducing impaired alveolarization, but failed to demonstrate any modification of the classical factors involved in lung development. We performed a genome-wide microarray analysis in 120 rat pups with LPD-induced IUGR and their controls, at three key time points of the alveolarization process: postnatal day 4 (P4): start of alveolarization; P10: peak of the alveolarization process and P21: end of the alveolarization process. Results were analysed using Arraymining, DAVID and KEGG software and validated by qRT-PCR and western blots. Considering a cut-off of 2:1 as significant, 67 transcripts at P4, 102 transcripts at P10 and 451 transcripts at P21 were up-regulated, and 89 transcripts at P4, 25 transcripts at P10 and 585 transcripts at P21 were down-regulated. Automatic functional classification identified three main modified pathways, 'cell adhesion molecules', 'cardiac muscle contraction' and 'peroxisome proliferator-activated receptor' (PPAR). Protein analysis confirmed involvement of the PPAR pathway, with an increase of FABP4, an activator of this pathway, at P4 and an increase of adiponectin at P21. Other data also suggest involvement of the PPAR pathway in impaired alveolarization. Our results show that deregulation of the PPAR pathway may be an important component of the mechanism inducing impaired alveolarization observed in IUGR. The complete dataset is available as GEO profiles on the Gene Expression Omnibus (GEO) database ( www.ncbi.nih.gov/geo/, GEO Accession No. GSE56956).

Antenatal infection in the rabbit impairs post-natal growth and lung alveolarisation.

Clinical and experimental studies indicate an association between chorioamnionitis and bronchopulmonary dysplasia in preterm infants. The present authors hypothesised that, in the rabbit, antenatal infection may impair lung development after birth, despite effective maternal antibiotic therapy. Pregnant rabbits received an intra-uterine inoculation of 10(3) Escherichia coli colony forming units or vehicle at the end of gestation (day 29). Intravenous ceftriaxone therapy was initiated 8 h after inoculation for a period of 8 days. Pups born between 60 and 84 h after inoculation were kept with their mother until sacrifice on days 0, 1, 5, 8 and 15. Blood cultures from antenatally infected animals were sterile at birth. Postnatal growth was significantly impaired by day 8. Lung morphometry showed a significant decrease of alveolar surface density and interstitial density, with a significant increase of alveolar airspace volume, indicating impaired alveolarisation for the first 2 weeks of postnatal life. Inflammatory and apoptotic processes were not detected in the lung at birth or subsequently. Intra-uterine infection in rabbits is, therefore, responsible for concomitant postnatal growth retardation and abnormal pulmonary development despite early and effective antenatal antibiotic therapy. This may constitute an alternative model to study the consequences of antenatal infection on postnatal growth and lung development.

Mast cells and cellularity of the colonic mucosa correlated with fatigue and depression in irritable bowel syndrome.

BACKGROUND: A subset of patients with irritable bowel syndrome (IBS) have an increased number of mast cells (MCs) in the colonic mucosa. Psychological factors are believed to contribute to the course of IBS. AIMS: To examine associations between fatigue, depression and MCs of the colonic mucosa in IBS. METHODS: Colonic biopsies were taken from 50 Rome II IBS patients, 21 healthy controls and 11 depressed/fatigued patients without IBS. The cellularity of the lamina propria was determined as the number of inflammatory cells per high power field (hpf) through a 400x microscope. The Fatigue Impact Scale (FIS) and the short form Beck Depression Inventory (BDI) evaluated the severity of fatigue and depression. RESULTS: IBS patients had a significant increase in the cellularity of the lamina propria compared with controls or with depressed patients (mean (SD) 94.5 (48-110) vs 68 (58-82) and 78 (87-90) cells per hpf, p = 0.005 and p = 0.05, respectively), in particular of MCs (9.3 (5.6-11.7) vs 4.0 (2.7-6.8) and 4.3 (2.8-7.8) cells per hpf, p = 0.001 and p = 0.005, respectively). Both the FIS and BDI scores were significantly higher in IBS or in depressed patients than in controls (p<0.001). In IBS, the FIS score correlated significantly with the cellularity of the lamina propria (r = 0.51, p<0.0001) and MCs (r = 0.64, p<0.0001). In IBS, the BDI score correlated significantly with MCs (r = 0.29, p = 0.03). CONCLUSIONS: Elevated MCs counts are a key feature of the low-grade inflammatory infiltrate in the caecal mucosa of IBS. Fatigue and depression are associated with mucosal cell counts, in particular MCs, suggesting that psychological factors are associated with the low-grade inflammatory infiltrate in IBS.

Fatigue is associated with high circulating leptin levels in chronic hepatitis C.

BACKGROUND AND AIMS: Fatigue is a frequent and disabling symptom reported by patients with chronic hepatitis C (CHC). Its mechanism is poorly understood. Recent attention has focused on the role of leptin and energy expenditure in CHC. Our aims were to analyse fatigue in CHC and to determine its relationship with disease activity, resting energy expenditure (REE), circulating leptin, and tumour necrosis factor alpha (TNF-alpha). METHODS: Seventy eight CHC patients, 22 healthy controls, and 13 primary biliary cirrhosis (PBC) patients underwent measurements of REE, body composition, leptin, and TNF-alpha. All subjects completed the fatigue impact scale (FIS) questionnaire. A liver biopsy and viral load measurements were performed in all patients. RESULTS: Thirty eight of 78 CHC patients considered fatigue the worst or initial symptom of their disease. The fatigue score of patients was significantly higher than that of controls (53.2 (40.1) v 17.7 (16.9); p<0.0001) and was more pronounced in females (p=0.003). Leptin was increased significantly in CHC patients compared with controls (15.4 (20.7) v 6.4 (4.1) ng/ml; p<0.05). In CHC patients, the fatigue score correlated significantly with leptin corrected for fat mass (r=0.30, p=0.01). This correlation increased when the physical domain of fatigue was included (r=0.39, p=0.0009). Furthermore, a similar positive correlation was found in PBC patients (r=0.56, p=0.04). No correlation was found between fatigue and age, REE, liver function tests, viral load, or the METAVIR score in CHC patients. CONCLUSIONS: Fatigue is present in CHC patients and is more pronounced in females. The FIS questionnaire is clinically relevant and may be useful for future therapeutic trials aimed at reducing fatigue. Fatigue may be partly mediated by leptin.

Overexpression of alveolar macrophage gelatinase B (MMP-9) in patients with idiopathic pulmonary fibrosis: effects of steroid and immunosuppressive treatment.

Alveolar macrophages (AM) express gelatinase B, a member of the matrix metalloproteinase family involved in the degradation and remodeling of extracellular matrix components. We evaluated the expression of gelatinase B in the course of idiopathic pulmonary fibrosis (IPF) by studying alveolar macrophages in culture AM and bronchoalveolar lavage fluid from 12 untreated patients with IPF, 11 patients with IPF under treatment with steroid and immunosuppressive agents, and 10 control subjects. By using zymography and quantitative image analysis, latent gelatinase B, as well an 88-kD active form, were investigated in culture medium (24 h) of AMs and were found to be significantly increased (P < 0.01) in untreated patients exhibiting severe IPF when compared with control subjects (4.1 +/- 1.7 versus 0.3 +/- 0.2 10(5) arbitrary units [AU]/10(4) AM for the 92-kD form). Concomitant studies of gelatinase B levels associated with cultured AM extracts or freshly harvested AM showed similar results, both at the mRNA and protein levels, respectively. Immunocytochemical studies on freshly harvested AM demonstrated that the enzyme was located mainly at the cell, suggesting some involvement of gelatinase B in AM migration. In contrast, gelatinase B activity secreted by AM tended to be normal in patients with IPF under steroid and immunosuppressive treatment. Simultaneously, level of the gelatinase B activity in epithelial lining fluid was increased in untreated IPF patients, whereas it was normal in treated patients. These results suggest that AM of patients with IPF are primed for gelatinase B expression and that steroid and immunosuppressive treatment induces negative modulation of the gelatinase B overexpression. We conclude that gelatinase B may play a role in lung remodeling in IPF.

Alveolar epithelial cells in vitro produce gelatinases and tissue inhibitor of matrix metalloproteinase-2.

Type II pneumocytes are key cells of the alveolar epithelium. They lie on the alveolar basement membrane, which influences their phenotype and functions. We hypothesized that type II pneumocytes degrade basement membrane components by producing gelatinases, members of the matrix metalloproteinase family. To investigate this hypothesis, we used primary cultures of rat type II pneumocytes and cultures of the human A549 cell line. We found by zymography that 70-kDa gelatinase was present in media conditioned by these cells. This 70-kDa gelatinase was identified as gelatinase A by a Western blot, and the presence of its mRNA was demonstrated by reverse transcription-polymerase chain reaction. A 95-kDa gelatinase could be induced under certain conditions. Production of gelatinases may take place during the turnover of basement membranes, in physiological and in pathophysiological processes. This was suggested by the increase in production of both gelatinases that we observed after in vitro exposure to LPS or interleukin-1. The presence of tissue inhibitors of matrix metalloproteinase-1 and -2 was also demonstrated, suggesting that degradation of extracellular matrix by type II pneumocytes is tightly regulated.

Pulmonary capillary diameters and recruitment characteristics in subpleural and interior networks.

In vivo microscopic observations of pulmonary capillaries are limited to subpleural networks that are less dense than interior networks. In addition to the density difference, subpleural and interior capillary diameters may differ, although there are conflicting data on this point. We measured the diameters of subpleural and interior capillaries in rats and dogs. Subpleural diameters were 30% larger in rats and 20% larger in dogs. Because diameter and density differences might cause differences in recruitment between subpleural and interior networks, we measured subpleural and interior recruitment by counting the number of red blood cells per 10 microns of alveolar wall in histological cross sections of rapidly frozen rat lungs. Lung inflation pressures of 4, 12, and 25 cmH2O created a wide range of capillary recruitment in different groups of animals. Red blood cell counts for interior and subpleural capillaries moved in parallel and progressively increased as inflation pressures were reduced. These data demonstrate that recruitment in subpleural capillaries accurately reflect recruitment in interior capillaries and validate the use of in vivo microscopic observations of subpleural capillaries to investigate pulmonary capillary recruitment in general.

[Cytological study of the duodenal mucosa during chronic diarrhea in HIV-positive patients]. / Etude cytologique de la muqueuse duodénale au cours des diarrhées chroniques chez le sujet VIH positif.

The cytologic findings of duodenal smears in diarrheic HIV-positive patients were compared with results of histologic and ultrastructural studies. This study included 50 diarrheic patients undergoing upper gastrointestinal endoscopy. Duodenal biopsies were taken with touch preparations. Smears were stained with Giemsa and then with Ziehl-Neelsen or the PAS method. The biopsy specimens were then processed in a standard fashion for histologic and electron microscopy examination. Cytologic findings included 8 cases of intestinal microsporidiosis, 4 cases of cryptosporidiosis, and 3 cases of atypical mycobacteriosis. Histologic and ultrastructural studies confirmed these diagnoses and showed 8 cases of CMV enteritis, of which 4 were associated with other enteric pathogens. Duodenal cytology complements endoscopic biopsy in the work-up of diarrhea in AIDS patients and may provide a rapid diagnosis especially in the case of intestinal protozoonosis or atypical intestinal mycobacteriosis.

[The use of molecular epidemiologic markers in the study of an epidemic outbreak of legionnaires' disease of nosocomial origin]. / Utilidad de los marcadores epidemiológicos moleculares en el estudio de un brote epidémico de enfermedad del legionario de origen nosocomial.

BACKGROUND: Epidemiological investigations of Legionella infections are based, since recently, on molecular techniques that are more sensitive and specific than phenotypic traits. We were interested in these methods for subtyping isolates of L. pneumophila serogroup 1 and confirm the epidemic spread of an outbreak of legionnaires' disease at the Universitary Hospital Germans Trias i Pujol (HUGTiP) in Badalona. METHODS: Environmental samples taken from domestic water, heating and cooling water systems and oxygen humidifiers were examined. Clinical and environmental isolates of L. pneumophila serogroup 1 were compared by analysis of genomic DNA by restriction endonucleases. RESULTS: We could found L. pneumophila serogroup 1 and 9 in domestic hot water and heating systems and L. micdadei in cooling water system. Cleavage of genomic DNA showed that all restriction fragment patterns coming from clinical and environmental isolates of L. pneumophila serogroup 1 were identical and different from isolates belonging to the same species and serogroup but coming from community area. CONCLUSIONS: Molecular analysis of clinical and environmental isolates of L. pneumophila serogroup 1 has allowed to identify a reservoir related to a nosocomial outbreak of legionnaires' disease at the HUGTiP, and a clonal population of L. pneumophila serogroup 1 in environmental samples genotypically identical to the clinical ones.

[Correction of severe malnutrition by cyclic enteral feeding]. / Correction des dénutritions sévères par l'alimentation entérale cyclique.

This study was designed to evaluate the efficacy and tolerance of cyclic (nocturnal) enteral nutrition in ambulatory malnourished patients. A ternary polymeric diet was administered to a total of 28 women and 23 men (mean age: 58 years) for a nocturnal period of 12-14 hours during 24.5 +/- 1.1 days. This diet provided an average of 28.3 +/- 0.6 kcal/kg ideal body weight/day. The nutritional program was administered as planned and well tolerated in 50 of the 51 patients. Voluntary oral caloric intake improved significantly during the treatment period (18.2 +/- 1.4 kcal/kg ideal body weight/day during the first week of enteral nutrition and 22.7 +/- 1.6 kcal/kg ideal body weight/day during the last week). The global nutritional deficit based on 10 anthropometric and biological parameters improved by an average of 36.8 +/- 2.2 percent. Overall, 71 percent of the patients exhibited a favorable nutritional course. Results were identical regardless of the pathology responsible for malnutrition. The main advantages of cyclic enteral nutrition include the possibility for patients to engage in physical activities and to eat normally during the day.

[Histopathologic features of opportunistic infections of the small intestine in acquired immunodeficiency syndrome]. / Aspects histopathologiques des infections opportunistes de l'intestin grêle au cours du syndrome d'immunodéficience acquis.

The frequency of the opportunistic infections of the duodenum in AIDS patients was determined by way of histologic study in 207 patients between January 1987 and June 1991. All cases had serial paraffin sections, run through HES, PAS, Giemsa, Brown-Brenn, and Zieh-Neelsen stains, and 20 cases had in addition cytologic and electron microscopic study. 63 patients had opportunistic infections (10 cryptosporidiosis and 2 isosporiasis; 12 mycobacterial enteritis; 15 CMV enteritis; 7 candidosis; 7 intestinal microsporidiosis confirmed by electron microscopic examination; 12 Giardiasis; 3 duodenal leishmaniasis; 1 intestinal cryptococcosis). Multiple concurrent infections were noted in 6 cases. A mild to severe villous atrophy was observed in 28 cases, associated with opportunistic infection. A patchy distribution of pathogen agent was noted in 34 cases, and 37 cases were associated with oesophagal candidosis. This study points out the value of histologic examination of intestinal biopsy for the diagnosis of systemic infections as well as of unusual parasitosis, and the necessity for multiple endoscopic biopsies because of the frequent patchy distribution of pathogens.

Influence of lung volume on histamine-induced bronchoconstriction in guinea-pigs.

The influence of lung volume on bronchopulmonary reactivity was investigated in 4 groups of 14 anaesthetized paralysed mechanically ventilated guinea-pigs: animals of group 1 served as control; in animals of group 2, the parasympathetic nervous system was blockaded with atropine; animals of group 3 were submitted to a bilateral cervical vagotomy; animals of group 4 were both vagotomized and pretreated with atropine. In each group, the animals were randomly divided into 2 subgroups: one was ventilated at zero end-expiratory pressure (ZEEP), the other with 0.2 kPa positive end-expiratory pressure (PEEP) resulting in a mean increase in lung volume of about 1 ml. Bronchopulmonary response to infused histamine was assessed by the respiratory conductance and compliance values measured during bronchoconstriction (respectively HGrs and HCrs). In the control group, animals exposed to PEEP were found significantly less reactive than those ventilated at ZEEP. In groups 2, 3 and 4, this difference was significantly reduced for HGrs and even abolished for HCrs. These results demonstrate that the effect of lung volume on moderate histamine-induced bronchoconstriction in guinea-pigs is not purely mechanical, but is partly vagally mediated. They also suggest that this vagally mediated inhibitory influence results from involvement of central reflexes evoked by stretch receptor stimulation.

[Bacteremia from Campylobacter fetus. Increasing interest and incidence]. / Bacteriemia por Campylobacter fetus. Interés e incidencia crecientes.

Three bacteremias of Campylobacter fetus were described. One was a male patient and two were females. Underlying illnesses were present in all of them (Hodgkin disease, AIDS and hepatic cirrhosis respectively). They were all admitted because of fever and no other symptoms of infectious focus were present. Physical findings were not relevant. The blood cultures became positive in days 6, 7 and 9 respectively. Antibiotic treatments were not standardised, so no conclusions can be drawn. The evolution was correct except for the patient infected by the human immunodeficiency virus who carried out a recurrent course. The authors comment on the increasing interest of this pathogen causing extraintestinal infection.