41 research outputs found
Genome-Scale Mining of Acetogens of the Genus Clostridium Unveils Distinctive Traits in [FeFe]- and [NiFe]-Hydrogenase Content and Maturation
Mastering hydrogen metabolism can support a sustainable carbon-neutral economy. Of the many microorganisms metabolizing hydrogen, acetogens of the genus Clostridium are appealing, with some of them already in usage as industrial workhorses.Knowledge of the organizational and functional properties of hydrogen metabolism is pivotal to the construction of a framework supportive of a hydrogen-fueled low-carbon economy. Hydrogen metabolism relies on the mechanism of action of hydrogenases. In this study, we investigated the genomes of several industrially relevant acetogens of the genus Clostridium (C. autoethanogenum, C. ljungdahlii, C. carboxidivorans, C. drakei, C. scatologenes, C. coskatii, C. ragsdalei, C. sp. AWRP) to systematically identify their intriguingly diversified hydrogenases' repertoire. An entirely computational annotation pipeline unveiled common and strain-specific traits in the functional content of [NiFe]- and [FeFe]-hydrogenases. Hydrogenases were identified and categorized into functionally distinct classes by the combination of sequence homology, with respect to a database of curated nonredundant hydrogenases, with the analysis of sequence patterns characteristic of the mode of action of [FeFe]- and [NiFe]-hydrogenases. The inspection of the genes in the neighborhood of the catalytic subunits unveiled a wide agreement between their genomic arrangement and the gene organization templates previously developed for the predicted hydrogenase classes. Subunits' characterization of the identified hydrogenases allowed us to glean some insights on the redox cofactor-binding determinants in the diaphorase subunits of the electron-bifurcating [FeFe]-hydrogenases. Finally, the reliability of the inferred hydrogenases was corroborated by the punctual analysis of the maturation proteins necessary for the biosynthesis of [NiFe]- and [FeFe]-hydrogenases. IMPORTANCE Mastering hydrogen metabolism can support a sustainable carbon-neutral economy. Of the many microorganisms metabolizing hydrogen, acetogens of the genus Clostridium are appealing, with some of them already in usage as industrial workhorses. Having provided detailed information on the hydrogenase content of an unprecedented number of clostridial acetogens at the gene level, our study represents a valuable knowledge base to deepen our understanding of hydrogenases' functional specificity and/or redundancy and to develop a large array of biotechnological processes. We also believe our study could serve as a basis for future strain-engineering approaches, acting at the hydrogenases' level or at the level of their maturation proteins. On the other side, the wealth of functional elements discussed in relation to the identified hydrogenases is worthy of further investigation by biochemical and structural studies to ultimately lead to the usage of these enzymes as valuable catalysts
The Coexistence of asthma and Chronic Ostructive Pulmonary Disease (COPD): prevalence and risk factors in young, middle-aged and elderly people from the general population
Background: The joint distribution of asthma and chronic obstructive pulmonary disease (COPD) has not been well described. This study aims at determining the prevalence of self-reported physician diagnoses of asthma, COPD and of the asthma-COPD overlap syndrome and to assess whether these conditions share a common set of risk factors.
Methods: A screening questionnaire on respiratory symptoms, diagnoses and risk factors was administered by mail or phone to random samples of the general Italian population aged 20â44 (n = 5163) 45â64 (n = 2167) and 65â84 (n = 1030) in the frame of the multicentre Gene Environment Interactions in Respiratory Diseases (GEIRD) study.
Results: A physician diagnosis of asthma or COPD (emphysema/chronic bronchitis/COPD) was reported by 13% and 21% of subjects aged <65 and 65â84 years respectively. Aging was associated with a marked decrease in the prevalence of diagnosed asthma (from 8.2% to 1.6%) and with a marked increase in the prevalence of diagnosed COPD (from 3.3% to 13.3%). The prevalence of the overlap of asthma and COPD was 1.6% (1.3%â2.0%), 2.1% (1.5%â2.8%) and 4.5% (3.2%â5.9%) in the 20â44, 45â64 and 65â84 age groups. Subjects with both asthma and COPD diagnoses were more likely to have respiratory symptoms, physical impairment, and to report hospital admissions compared to asthma or COPD alone (p<0.01). Age, sex, education and smoking showed different and sometimes opposite associations with the three conditions.
Conclusion: Asthma and COPD are common in the general population, and they coexist in a substantial proportion of subjects. The asthma-COPD overlap syndrome represents an important clinical phenotype that deserves more medical attention and further research.</br
Latitude variation in the prevalence of asthma and allergic rhinitis in Italy: results from the GEIRD study
BACKGROUND: Earlier studies have pointed out a great variability in the prevalence of asthma and
asthma-like symptoms in different geo-climatic areas. AIM: To test the association between latitude and
prevalence of asthma and allergic rhinitis in Italian young adults. METHODS: In the frame of
Gene-Environment Interaction in Respiratory Diseases study, a postal screening questionnaire on
respiratory health and exposure to environmental factors was administered to 18,357 randomly selected
subjects aged 20-44 years in 7 centres: 3 in Northern (Torino, Pavia, Verona), 2 in Central (Ancona,
Perugia) and 2 in Southern Italy (Salerno, Sassari). RESULTS: 10,494 (57.2%) subjects responded to the
questionnaire. The prevalence of self-reported doctor-diagnosed asthma and allergic rhinitis in the lifespan
was 10.2% and 26.9%, respectively, and was significantly different across the centres (p<0.05). After
adjusting for sex, age, potential risk factors for respiratory diseases and design confounders, the prevalence
of asthma (OR: 1.07 per 1°latitude decrease, p<0.001), asthma-like symptoms (wheezing, chest tightness,
asthma attacks: OR ranging from 1.04 to 1.06, p<0.05) and allergic rhinitis (OR: 1.03, p=0.04) showed a
significant north-to-south trend. Similarly, a 1°C increment in temperature was significantly associated with
asthma (OR: 1.10, p<0.001) and asthma-like symptoms (OR from 1.07 to 1.10, p<0.05), but not with allergic
rhinitis (OR=1.02, p=0.190). CONCLUSION: The prevalence of asthma and allergic rhinitis increased
moving southwards in Italy, suggesting that prolonged exposure to different geo-climatic conditions may
affect the onset of asthma and allergic respiratory diseases
Asthma-related deaths
Despite major advances in the treatment of asthma and the development of several asthma guidelines, people still die of asthma currently. According to WHO estimates, approximately 250,000 people die prematurely each year from asthma. Trends of asthma mortality rates vary very widely across countries, age and ethnic groups. Several risk factors have been associated with asthma mortality, including a history of near-fatal asthma requiring intubation and mechanical ventilation, hospitalization or emergency care visit for asthma in the past year, currently using or having recently stopped using oral corticosteroids (a marker of event severity), not currently using inhaled corticosteroids, a history of psychiatric disease or psychosocial problems, poor adherence with asthma medications and/or poor adherence with (or lack of) a written asthma action plan, food allergy in a patient with asthma. Preventable factors have been identified in the majority of asthma deaths. Inadequate education of patients on recognising risk and the appropriate action needed when asthma control is poor, deficiencies in the accuracy and timing of asthma diagnosis, inadequate classification of severity and treatment, seem to play a part in the majority of asthma deaths. Improvements in management, epitomized by the use of guided self-management systems of care may be the key goals in reducing asthma mortality worldwide
OUTCOMES OF ELDERLY PATIENTS WITH ST-ELEVATION OR NON-ST-ELEVATION ACUTE CORONARY SYNDROME UNDERGOING PERCUTANEOUS CORONARY INTERVENTION
Acute coronary syndromes have been classified according to the finding of ST-segment elevation on the presenting ECG, with different treatment strategies and practice guidelines. However, a comparative description of the clinical characteristics and outcomes of acute coronary syndrome elderly patients undergoing percutaneous coronary intervention during index admission has not been published so far
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La nostra ricerca ha lo scopo di effettuare una comparazione tra due metodologie per 1\'insegnamento delia pronuncia sottoposte agli studenti di due gruppi di conversazione dei corsi extracurriculari. Si focalizzerĂ 1\'attenzione principalmente sulla pronuncia delle consonanti geminate delia lingua italiana. II lavoro si articola in quattro capitoli. II primo capitolo aborda il tema deli\'origine storica delle consonanti geminate; nel secondo capitolo Ă© stata fatta un\'analisi contrastiva dei suoni delia lingua italiana e di quelli del portoghese pariato in Brasile. II terzo capitolo descrive la formazione di una lista di parole italiane frequenti che contengono delle consonanti geminate da dove sono State estratte le parole presentate agli studenti in classe alio scopo di raccogliere infomazioni sulle diffĂcoltĂ e sugli errori da questi commessi. 11 quarto ed ultimo capitolo, presenta le due metodologie che sono State utilizzate per far esercitare gli studenti sulla pronuncia e sulla trascrizione fonologica, delinea anche come sono State svolte a lezione le attivitĂ per introdurre parole delia lista citata precedente. Alia fine delia ricerca, le informazioni raccolte sono State analizzate determinando la performance degli studenti e l\'effĂcacia delle due metodologie comparateA nossa pesquisa visa efetuar uma comparação entre duas metodologias de ensino da pronĂșncia, aplicadas aos alunos de duas turmas de conversação nos cursos de italiano extracurricular, focalizando a atenção sobre a pronĂșncia das consoantes geminadas da lĂngua italiana. O trabalho estĂĄ estruturado em quatro capĂtulos. O primeiro capĂtulo faz uma abordagem da origem histĂłrica das consoantes geminadas; o segundo capĂtulo Ă© feita uma anĂĄlise contrastiva dos sons da lĂngua italiana e da lĂngua portuguesa falada no Brasil. O terceiro capĂtulo descreve a formação de uma lista de palavras frequentes na lĂngua italiana que contĂ©m consoantes geminadas, de onde foram extraĂdas as palavras apresentadas aos alunos em sala de aula, no intuito de coletar informaçÔes sobre as dificuldades e os erros por eles cometidos. O quarto e Ășltimo capĂtulo, apresenta as duas metodologias que foram utilizadas para treinar os alunos na pronĂșncia e na transcrição fonolĂłgica, bem como as atividades desenvolvidas em sala de aula para introduzir as palavras da lista acima citada. As informaçÔes coletadas foram finalmente analisadas determinando a performance dos alunos e a eficĂĄcia das duas metodologias comparada