175 research outputs found
Molecular characterization of a glycosylphosphatidylinositol-linked ADP-ribosyltransferase from lymphocytes
No full textMono ADP-ribosyltransferases catalyze the transfer of the ADP-ribose moiety of nicotinamide adenine dinucleotide (NAD) to proteins. It was reported by Wang et al (J Immunol 153:4048, 1994) that incubation of mouse cytotoxic T lymphocytes (CTL) with NAD resulted in the ADP-ribosylation of membrane proteins and inhibition of cell proliferation and cytotoxicity. Treatment of CTL with phosphatidylinositol-specific phospholipase C (PI-PLC) before incubation with NAD prevented the inhibitory effects of NAD on the cells, consistent with the removal of a glycosylphosphatidylinositol (GPI)-anchored ADP-ribosyltransferase on the lymphocyte surface. We have identified and cloned a GPI-linked ADP-ribosyltransferase from Yac-1 mouse T-cell lymphoma cells. The deduced amino acid sequence of the Yac-1 transferase was 70% and 41% identical to those of the rabbit skeletal muscle and chicken heterophil, respectively. It contained three noncontiguous sequences similar to those found in several of the bacterial toxin and vertebrate ADP-ribosyltransferases. Based on crystallography of the bacterial toxins, these regions are believed to form, in part, the catalytic site consistent with a common mechanism for the ADP-ribose transfer reaction. In rat mammary adenocarcinoma (NMU) cells transformed with the Yac-1 transferase cDNA, transferase activity was present on the cell surface and was released into the medium by treatment of cells with PI-PLC. Thus, we have cloned a novel gene that has properties identical to the transferase detected in CTL, and may be involved in the NAD-dependent regulation of proliferation and cytotoxicit
Inhaled aztreonam lysine vs. inhaled tobramycin in cystic fibrosis: a comparative efficacy trial.
No full textBackground: Open-label, parallel-group, international trial comparing aztreonam for inhalation solution (AZLI) and tobramycin nebulizer solution (TNS) for cystic fibrosis patients with airway Pseudomonas aeruginosa.
Methods: 273 patients (≥ 6 years); randomized to three 28-day courses (AZLI 75 mg [three-times/day] or TNS 300 mg [twice/day]); 28 off-days separated each course.
Results: 268 patients were treated (AZLI/TNS: 136/132). Mean baseline FEV1 was 52% predicted. Mean relative changes after 1 course (AZLI: 8.35%; TNS: 0.55%; p<0.001) and mean actual changes across 3 courses (AZLI: 2.05%; TNS: -0.66%; p=0.002) indicated AZLI statistical superiority vs. TNS. AZLI-treated patients had fewer respiratory hospitalizations (p=0.044) and respiratory events requiring additional antipseudomonal antibiotics (p=0.004); both treatments were well tolerated. 133 patients received 1 to 3 courses of AZLI treatment in the open-label extension-period (28-day courses separated by 28 days off-treatment); lung function improvements were comparable regardless of whether patients had received TNS or AZLI in the preceding comparative period.
Conclusions: AZLI demonstrated statistical superiority in lung function and a reduction in acute pulmonary exacerbations compared to TNS over 3 treatment courses (ClinicalTrials.gov: NCT00757237)
Comprehensive Clinical Diagnostic Pipelines Reveal New Variants in Alpha-1 Antitrypsin Deficiency
No full text: Alpha-1 antitrypsin deficiency (AATD) is an underdiagnosed disorder associated with mutations in the SERPINA1 gene encoding alpha-1 antitrypsin (AAT). Severe AATD can manifest as pulmonary emphysema and progressive liver disease. Besides the most common pathogenic variants S (E264V) and Z (E342K), many rarer genetic variants of AAT have been found in patients and in the general population. Here we report a panel of new SERPINA1 variants, including 4 null and 16 missense alleles, identified among a cohort of individuals with suspected AATD whose phenotypic follow-up showed inconclusive or atypical results. Because the pathogenic significance of the missense variants was unclear purely on the basis of clinical data, the integration of computational, biochemical, and cellular studies was used to define the associated risk of disease. Established pathogenicity predictors and structural analysis identified a panel of candidate damaging mutations that were characterized by expression in mammalian cell models. Polymer formation, intracellular accumulation, and secretory efficiency were evaluated experimentally. Our results identified two AAT mutants with a Z-like polymerogenic severe deficiency profile (Smilano and Mcampolongo) and three milder variants (Xsarezzo, Pdublin, and Ctiberias). Overall, the experimentally determined behavior of the variants was in agreement with the pathogenicity scores of the REVEL (an ensemble method for predicting the pathogenicity of rare missense variants) predictor, supporting the utility of this bioinformatic tool in the initial assessment of newly identified amino acid substitutions of AAT. Our study, in addition to describing 20 new SERPINA1 variants, provides a model for a multidisciplinary approach to classification of rare AAT variants and their clinical impact on individuals with rare AATD genotypes
Identification and characterisation of eight novel SERPINA1 null mutations.
No full textBackground:Alpha-1 antitrypsin (AAT) is the most abundant circulating antiprotease and is a member of the serine protease inhibitor (SERPIN) superfamily. The gene encoding AAT is the highly polymorphic SERPINA1 gene, found at 14q32.1. Mutations in the SERPINA1 gene can lead to AAT deficiency (AATD) which is associated with a substantially increased risk of lung and liver disease. The most common pathogenic AAT variant is Z (Glu342Lys) which causes AAT to misfold and polymerise within hepatocytes and other AAT-producing cells. A group of rare mutations causing AATD, termed Null or Q0, are characterised by a complete absence of AAT in the plasma. While ultra rare, these mutations confer a particularly high risk of emphysema. Methods: We performed the determination of AAT serum levels by a rate immune nephelometric method or by immune turbidimetry. The phenotype was determined by isoelectric focusing analysis on agarose gel with specific immunological detection. DNA was isolated from whole peripheral blood or dried blood spot (DBS) samples using a commercial extraction kit. The new mutations were identified by sequencing all coding exons (II-V) of the SERPINA1 gene. Results: We have found eight previously unidentified SERPINA1 Null mutations, named: Q0cork, Q0perugia, Q0brescia, Q0torino, Q0cosenza, Q0pordenone, Q0lampedusa, and Q0dublin . Analysis of clinical characteristics revealed evidence of the recurrence of lung symptoms (dyspnoea, cough) and lung diseases (emphysema, asthma, chronic bronchitis) in M/Null subjects, over 45 years-old, irrespective of smoking. Conclusions: We have added eight more mutations to the list of SERPINA1 Null alleles. This study underlines that the laboratory diagnosis of AATD is not just a matter of degree, because the precise determination of the deficiency and Null alleles carried by an AATD individual may help to evaluate the risk for the lung disease
High concentrations of pepsin in bronchoalveolar lavage fluid from children with cystic fibrosis are associated with high interleukin-8 concentrations
No full textBackground. Gastro-oesophageal reflux is common in children with cystic fibrosis (CF) and is thought to be associated with pulmonary aspiration of gastric contents. The measurement of pepsin in bronchoalveolar lavage (BAL) fluid has recently been suggested to be a reliable indicator of aspiration. The prevalence of pulmonary aspiration in a group of children with CF was assessed and its association with lung inflammation investigated.Methods. This was a cross-sectional case-control study. BAL fluid was collected from individuals with CF (n¼31) and healthy controls (n¼7). Interleukin-8 (IL-8), pepsin, neutrophil numbers and neutrophil elastase activity levels were measured in all samples. Clinical, microbiological and lung function data were collected from medical notes.Results. The pepsin concentration in BAL fluid was higher in the CF group than in controls (mean (SD) 24.4 (27.4) ng/ml vs 4.3 (4.0) ng/ml, p¼0.03). Those with CF who had raised pepsin concentrations had higher levels of IL-8 in the BAL fluid than those with a concentration comparable to controls (3.7 (2.7) ng/ml vs 1.4 (0.9) ng/ml, p¼0.004). Within the CF group there was a moderate positive correlation between pepsin concentration and IL-8 in BAL fluid (r¼0.48, p¼0.04). There was no association between BAL fluid pepsin concentrations and age, sex, body mass index z score, forced expiratory volume in 1 s or Pseudomonas aeruginosa colonisation status.Conclusions. Many children with CF have increased levels of pepsin in the BAL fluid compared with normal controls. Increased pepsin levels were associated with higher IL-8 concentrations in BAL fluid. These data suggest that aspiration of gastric contents occurs in a subset of patients with CF and is associated with more pronounced lung inflammation
European Respiratory Society statement : Diagnosis and treatment of pulmonary disease in α1-antitrypsin deficiency
No full textα1-antitrypsin deficiency (AATD) is the most common hereditary disorder in adults. It is associated with an increased risk of developing pulmonary emphysema and liver disease. The pulmonary emphysema in AATD is strongly linked to smoking, but even a proportion of never-smokers develop progressive lung disease. A large proportion of individuals affected remain undiagnosed and therefore without access to appropriate care and treatment. The most recent international statement on AATD was published by the American Thoracic Society and the European Respiratory Society in 2003. Since then there has been a continuous development of novel, more accurate and less expensive genetic diagnostic methods. Furthermore, new outcome parameters have been developed and validated for use in clinical trials and a new series of observational and randomised clinical trials have provided more evidence concerning the efficacy and safety of augmentation therapy, the only specific treatment available for the pulmonary disease associated with AATD. As AATD is a rare disease, it is crucial to organise national and international registries and collect information prospectively about the natural history of the disease. Management of AATD patients must be supervised by national or regional expert centres and inequalities in access to therapies across Europe should be addressed
Nessun Kurtz : cuore di tenebra e le parole dell'occidente
No full textIl volume si configura come una riflessione sulla tragedia infinita delle migrazioni nel Mediterraneo, scegliendo una chiave interpretativa precisa, ovvero concentrandosi sui tentativi di “raccontarla” – attraverso la letteratura, il cinema e le arti – dal punto di vista dell’occidente. Non è casuale che in tutti gli ambiti indicati vengano scelti come testi campione opere realizzate da artisti occidentali, che, attraverso lo strumento della rappresentazione, cercano in modi diversi di calarsi nei panni del migrante, riempiendo un vuoto di voci che traduce una difficoltà dell’Occidente a superare le forme stereotipate dell’alterità. Nella comunicazione giornalistica corrente come nel senso comune, quella che viene presentata sempre più spesso come una “invasione” è in realtà un fenomeno che, prima di essere collettivo e indiversificato, raccoglie una quantità di individui, con una storia personale e culturale, una tradizione, una identità specifica, spesso cancellata dalla conta dei morti. La rappresentazione artistica, quando riesce, cerca di recuperare il senso di questa individualità e si sforza di superare lo stereotipo così caro alle semplificazioni delle politiche del respingimento e allo spirito neopastorale delle forme di pietà.
Dietro questa scelta di analisi sta anche una domanda importante, così frequente nella cultura europea contemporanea: a che cosa serve la letteratura? E’ proprio vero – come sembra suggerire l’accantonamento dei saperi umanistici in favore di scienze dure – che l’arte è un bene inutile e la formazione in questo campo velleitaria? La convinzione sulla quale questo testo si basa, peraltro sostenuta da recenti studi europei, è che sia vero il contrario. La rappresentazione letteraria e artistica anticipa, media, aiuta la comprensione di fenomeni dirompenti, ed è dunque necessaria come nessun’altra forma di ricerca in questo momento. Nel caso specifico di Nessun Kurtz, è questo il motivo per cui lo studio parte da Cuore di tenebra, di J. Conrad, come testo fondante nel definire la strada maestra seguendo la quale si definisce un rapporto con l’Altro che ha coordinate complicate e che ha rappresentato fin qui, spesso, un ostacolo alla conoscenza reale. Il mistero che Conrad intravvede e rappresenta attraverso la vicenda di Kurtz, il modo in cui questa vicenda viene riscritta e ri-mediata nel cinema (Apocalypse Now, di F. F. Coppola) e nella narrativa (The Butt, di Will Self) rappresenta un paradigma che ispira, consapevolmente e inconsapevolmente molte rappresentazioni della contemporaneità, letterarie C. Cleave, M. De Kerangal, G. Catozzella, M. mazzantini, J. Erpenbeck), filmiche (O. Welles, A. Maglio e M. Paolos, D. Iannacone e L. Cambi), fotografiche (M. Badagliacca, M. De Carolis, K. McElvaney) e teatrali (L. Prosa, A. Lustgarten, C. Pite). Tornare al Kurtz conradiano, dunque, aiuta a ricostruire la genealogia di uno stereotipo e a trovare le parole giuste per fare dello stereotipo una persona
The European Alpha-1 antitrypsin Deficiency Research Collaboration (EARCO). A new ERS Clinical Research Collaboration to promote research in alpha-1 antitrypsin deficiency
No full textPathogenesis and treatment of chronic pulmonary disease
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