1,721,238 research outputs found
Disentangling the role of wild birds in avian metapneumovirus (aMPV) epidemiology: A systematic review and meta-analysis
Full text linkGiven the avian metapneumovirus (aMPV) disease burden in poultry worldwide and the evidence of a possible role played by wild birds in the virus epidemiology, the present study summarizes aMPV serological and molecular data on free-ranging avifauna available in the literature by conducting a systematic review and meta-analysis. A computerized literature research was performed on PubMed, Scopus, CAB Direct and Web of Science to identify relevant publications across the period 1990–2021, along with the screening of reference lists. A random-effect model was applied to calculate pooled prevalence estimates with 95% confidence intervals. The inconsistency index statistic (I2) was applied to assess between-study heterogeneity. Subgroup analyses for molecular studies only were performed according to geographical area of samplings, taxonomic order, genus and migration patterns of the birds surveyed. A total of 11 publications on molecular surveys and 6 on serological ones were retained for analysis. The pooled molecular prevalence was 6% (95% CI: 1–13%) and a high between-study heterogeneity was detected (I2 = 96%, p <.01). Moderator analyses showed statistically significant differences according to geographical area studied, taxonomic order and genus. Concerning serological prevalence, a pooled estimate of 14% (95% CI: 1–39%), along with a high between-study heterogeneity, was obtained (I2 = 98%, p <.01). Moderator analysis was not performed due to the scarcity of eligible serological studies included. Overall, molecular and serological evidence suggests that some wild bird taxa could play a role in aMPV epidemiology. Particularly, wild ducks, geese, gulls and pheasants, according to scientific contributions hereby considered, proved to be susceptible to aMPV, and due to host ecology, may act as a viral carrier or reservoir. Further surveys of wild birds are encouraged for a better comprehension of the poultry/wild bird interface in aMPV epidemiology and for better characterizing the virus host breadth
New PCR test for the molecular detection of avian pneumovirus
No full textThis study described the design and sensitivities of PCR tests used to detect DNA copies of an A type avian pneumovirus (APV). The objective was selection of PCR primer combinations which would provide the greatest test sensitivity for later testing of field materials. Sensitivities could be determined because of laboratory access to known quantities of purified full length DNA copies of a complete APV genome. Four new nested PCR tests were designed in the fusion (F) protein [2 tests], small hydrophobic (SH) protein and nucleocapsid (N) protein genes and compared to an established test in the attachment (G) protein gene. Sensitivities were found to differ between the tests with the most sensitive being the established G test. When one of the F PCRs was modified to position pyrimidine residues at all primer 3’ termini, its sensitivity exceeded that of the established G test and was chosen for use in future diagnostic testing
Caracterización superficial de pigmentos sobre artefactos paleolíticos de la zona de los Montes Albanos (Roma, Italia) por microscopía óptica y espectroscopía raman
Full text linkPreliminary results of the characterization of red pigmentations on paleolithic artefacts from the southern area of
Montes Albanos (Rome, Italy) are presented. The set of materials consists of three decorated rounded pebblestones and a cortical flint blade typologically attributable to the Upper Paleolithic (Final Epigravetense, 14,000-12,000 cal BP). The findings were observed with optical microscope Nikon SMZ 1000/800 with magnifications of 1x to 6.3x. In two pebblestones, one decorated with parallel engravings, residues of ocher were detected in association with traces of use. In the third one, stained red dye was observed to form geometric patterns. Finally, reddish pigmentations were located on the cortical dorsal surface of a flint blade. To characterize chemically the coloring agent detected, macro-microscopically, Raman spectroscopy was used, a technique that allowed the study of the nature of the residues and the detection of additional organic materials whose presence must be related to post-depositional contaminations produced by the manipulation or/and surface exposure of artifacts
Construction of a green fluorescent protein (GFP) Avian Metapneumovirus (AMPV) recombinant lacking the small hydrophobic (SH) protein gene shows that giant syncytial formations are not a result of the reduction in genome size
No full textAn AMPV reverse-genetics system was used to create a virus lacking the entire SH open reading frame which produced unusual giant syncytial formation in cell culture. The replacement of the gene with GFP resulted in virus which also produced the same syncytial formation. The intrinsic fluorescent properties of the virus may prove useful in pathogenesis studies. The similarity of size of the 2 genes suggests that the altered cytopathic effect did not result from the shortening of the genome and possible consequential effects on the transcription or translation of the following attachment and polymerase protein genes
Construction of GFP Avian Metapneumovirus (AMPV) recombinant lacking the small hydrophobic protein gene
No full textAn AMPV reverse-genetics system was used to create a virus lacking the entire SH
open reading frame which produced unusual giant syncytial formations in cell culture.
The replacement of the gene with GFP resulted in virus which also produced the
same syncytial formations. The intrinsic fluorescent properties of the virus may prove
useful in pathogenesis studies. The similarity of size of the 2 genes suggests that the
altered cytopathic effect did not result from the shortening of the genome and
possible consequential effects on the transcription or translation of the following
attachment and polymerase protein genes
In vitro antiviral activity of Chestnut (Castanea spp.), Quebracho (Schinopsis spp.) and Tara (Caesalpinia spinosa) extracts against Avian Reovirus and Metapneumovirus
No full text- …
