1,720,972 research outputs found
Longer resistance of some DNA traits from BT176 maize to gastric juice from gastrointestinal affected patients
No full textThe presence of antibiotic resistance marker genes in genetically engineered plants is one of the most controversial issues related to Genetically Modified Organism (GMO)-containing food, raising concern about the possibility that these markers could increase the pool of antibiotic resistance genes. This study investigates the in vitro survival of genes bla and cryIA(b) of maize Bt176 in human gastric juice samples. Five samples of gastric juice were collected from patients affected by gastro-esophageal reflux or celiac disease and three additional samples were obtained by pH modification with NaHCO3. DNA was extracted from maize Bt176 and incubated with samples of gastric juices at different times. The survival of the target traits (bla gene, whole 1914 bp gene cry1A(b), and its 211 bp fragment) was determined using PCR. The stability of the target genes was an inverse function of their lengths in all the samples. Survival in samples from untreated subjects was below the normal physiological time of gastric digestion. On the contrary, survival time in samples from patients under anti-acid drug treatment or in samples whose pH was modified, resulted strongly increased. Our data indicate the possibility that in particular cases the survival time could be so delayed that, as a consequence, some traits of DNA could reach the intestine. In general, this aspect must be considered for vulnerable consumers (people suffering from gastrointestinal diseases related to altered digestive functionality, physiological problems or drug side-effects) in the risk analysis usually referred to healthy subjects
Identificazione del virus dell'epatite E in allevamenti suini nella provincia di Modena.
No full textWidespread diffusion of Genotype 3 Hepatitis E Virus among farming swine in Northern Italy.
No full textHepatitis E virus (HEV) causes acute hepatitis in humans, and infects several animal species, mostly asymptomatically. Swine and human HEV strains are genetically related suggesting both a zoonotic and a possible foodborne transmission. The prevalence of swine HEV was investigated in 274 randomly selected pigs from six different swine farms of Northern Italy, testing viral RNA in stools by nested reverse-transcription-polymerase chain reaction. HEV genome was detected in 115 stools (42%). All farms resulted positive for HEV, with a prevalence ranging between 12.8% and 72.5%. HEV-positive pigs were detected in all age groups and production stages tested, although infection was more prevalent in weaners than in the older fatteners (42.2% vs. 27.0%). Genetic characterization of swine strains identified was performed by sequencing and database alignment. Phylogenetic analysis on the nucleotide sequences from 16 positive PCR products indicated that all strains belonged to genotype 3. In particular, one group of seven Italian strains clustered close (91.6–96.2% identity) to human and swine European HEV strains
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Valutazione della prevalenza e dei fattori di rischio relativi all’infezione da virus dell'epatite E (HEV) in allevamenti suini italiani : risultati preliminari
No full textL’agente eziologico dell’epatite E (HEV) è un virus a RNA di piccole dimensioni privo di envelope. Nel suino domestico, il virus è responsabile solo di infezioni sub-cliniche con segni di epatite rilevabile esclusivamente a livello istologico, tuttavia ceppi di HEV di origine suina sono spesso risultati geneticamente simili ai ceppi responsabili di episodi sporadici di malattia nell’uomo. Recentemente casi umani di epatite E sono stati correlati al consumo di carne o organi crudi o poco cotti di suino, cinghiale e cervo e la malattia viene oggi considerata una zoonosi emergente trasmissibile, con gli alimenti. Scopo del presente lavoro è stata la valutazione preliminare della prevalenza e dei fattori di rischio relativi all’infezione da HEV in alcune aziende suinicole del Nord Italia. 274 campioni fecali prelevati da suini di 6 aziende da riproduzione o riproduzione-ingrasso sono stati analizzati per la ricerca del genoma di HEV utilizzando una metodica di RT-Nested-PCR. I campioni sono stati prelevati sia da soggetti all’ingrasso sia da riproduttori. Tutti gli animali esaminati apparivano clinicamente sani al momento del campionamento. L’RNA virale estratto dai campioni fecali è stato retrotrascritto e amplificato mediante una RT-Nested-PCR che utilizza due coppie di primers disegnati sulla regione genomica ORF2. Per l’identificazione di alcuni dei possibili fattori di rischio legati all’infezione, la prevalenza negli allevamenti è stata valutata in funzione della categoria di appartenenza dei soggetti (magroni, grassi, scofette, scrofe giovani, scrofe anziane) e delle dimensioni dell’allevamento (numero di scrofe presenti). Per la caratterizzazione dei ceppi individuati, alcuni campioni positivi scelti in maniera casuale sono stati sottoposti a sequenziamento. I frammenti sequenziati sono stati allineati con quelli presenti nella banca dati NCBI e analizzati utilizzando il software DNASIS Max. Sessantanove (25,2%) dei 274 campioni fecali analizzati sono risultati positivi per HEV. La prevalenza nelle 6 aziende esaminate variava dal 2% al 60,5%. La proporzione di animali positivi per HEV nella categoria dei magroni e delle scrofette è risultata rispettivamente 3,6 e 3,4 volte più elevata che negli animali a fine ciclo produttivo, mentre la prevalenza non è risultata significativamente correlata alle dimensioni aziendali. Tutti i campioni geneticamente caratterizzati sono risultati appartenere al genotipo 3 di HEV. Questi risultati preliminari confermano una larga diffusione dell’infezione da HEV nelle aziende suine italiane
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Prevalence of hepatitis E virus in Italian pig herds. Preliminary results
No full textHepatitis E virus (HEV) is the causative agent of hepatitis E, and is an unenveloped positive sense single-stranded RNA virus. Swine HEV strains are genetically closely related to human strains from the same area, suggesting the occurrence of zoonotic transmission. Recently, human cases of hepatitis E have been linked to the consumption of raw or undercooked meat or organs from deer, wild boars or pigs. The disease is now considered an emerging food-borne transmitted zoonosis. During 2006, a pilot investigation was performed to determine the prevalence of HEV in pig farms located in Northern Italy., 274 faecal samples were collected from healthy fattening animals (3-4 and 8-9 months of age) and from healthy breeding animals (gilts and sows) from 6 different farms and analyzed using a Nested-RT-PCR targeting the open reading frame 2 (ORF2) region. Stool samples were suspended in water, and viral RNA extraction was performed using a commercial kit. Extracted viral RNA was subjected to RT-PCR amplification using degenerate primers conA1-conS1 for the first amplification, and degenerate primers conA2-conS2 for the nested PCR, yielding a final fragment of 145 bp. HEV RNA was detected in sixty-nine of the 274 (25.2%) examined samples. None of the six farms resulted negative and the prevalence within the farms ranged between 2% and 60.5% For the characterization of the strains, randomly selected positive samples were subjected to nucleotide sequencing, and aligned with those present in the NCBI Data Bank Sequence analysis showed that all strains were Swine Hepatitis E belonging to Genotype 3. These preliminary results confirm that swine HEV is widespread in Italian swine farms
Characterization of ORF2 of swine strains of Hepatits E virus in Italy
No full textHepatitis E virus (HEV) is the causative agent of hepatitis E, and is an unenveloped positive sense single-stranded RNA virus. The genome of HEV is approximately 7.2 kb and contains three open reading frames. ORF1 encodes non structural proteins, and ORF2 and 3 code for the capsid protein and a small protein of unknown function, respectively. HEV is an emerging public health concern in many developing countries, where it can cause large epidemics mainly via contaminated water. Swine HEV strains are genetically close to human strains from the same area, suggesting the
occurrence of zoonotic transmission. This route might play an important role in spreading infection also in Europe and other industrialized areas. Recently, hepatitis E cases have been linked to eating raw or undercooked meat from deer, wild boars or pigs. Detection of virus in stools or bile relies onto nested-RT-PCR protocols targeting the ORF2 region, and is particularly troublesome in swines due to the occurrence of asymptomatic infections.
A pilot investigation was performed to identify the presence of HEV swine infection within farm in Northern Italy. Results of molecular diagnostic assays indicate the presence of genotype 3 HEV strains in Northern Italy. Viral genomic RNAs from positive samples were used to obtain a full length fragment of ORF2. Improved quantitative PCR technology and development of immunological reagents maybe useful for improving surveillance and control of hepatitis E infection
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