scholarly journals TaqMan probe assays on different biological samples for the identification of three ambrosia beetle species, Xylosandrus compactus (Eichoff), X. crassiusculus (Motschulsky) and X. germanus (Blandford) (Coleoptera Curculionidae Scolytinae)

3 Biotech ◽  
2021 ◽  
Vol 11 (6) ◽  
Author(s):  
Domenico Rizzo ◽  
Daniele Da Lio ◽  
Linda Bartolini ◽  
Chiara Salemi ◽  
Dalia Del Nista ◽  
...  

AbstractMolecular assays based on qPCR TaqMan Probes were developed to identify three species of the genus Xylosandrus, X. compactus, X. crassiusculus and X. germanus (Coleoptera Curculionidae Scolytinae). These ambrosia beetles are xylophagous species alien to Europe, causing damages to many ornamental and fruiting trees as well as shrubs. DNA extraction was carried out from adults, larvae and biological samples derived from insect damages on infested plants. For X. compactus, segments of galleries in thin infested twigs were cut and processed; in the case of X. crassiusculus, raw frass extruded from exit holes was used, while DNA of X. germanus was extracted from small wood chips removed around insect exit holes. The assays were inclusive for the target species and exclusive for all the non-target species tested. The LoD was 3.2 pg/µL for the frass of X. crassiusculus and 0.016 ng/µL for the woody matrices of the other two species. Both repeatability and reproducibility were estimated on adults and woody samples, showing very low values ranging between 0.00 and 4.11. Thus, the proposed diagnostic assays resulted to be very efficient also on the woody matrices used for DNA extraction, demonstrating the applicability of the protocol in the absence of dead specimens or living stages.

Author(s):  
Ute Eberle ◽  
◽  
Clara Wimmer ◽  
Ingrid Huber ◽  
Antonie Neubauer-Juric ◽  
...  

AbstractTo face the COVID-19 pandemic, the need for fast and reliable diagnostic assays for the detection of SARS-CoV-2 is immense. We describe our laboratory experiences evaluating nine commercially available real-time RT-PCR assays. We found that assays differed considerably in performance and validation before routine use is mandatory.


Diagnostics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 78
Author(s):  
Anja Dörschug ◽  
Julian Schwanbeck ◽  
Andreas Hahn ◽  
Anke Hillebrecht ◽  
Sabine Blaschke ◽  
...  

Serological assays can contribute to the estimation of population proportions with previous immunologically relevant contact with the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) virus. In this study, we compared five commercially available diagnostic assays for the diagnostic identification of SARS-CoV-2-specific antibodies. Depending on the assessed immunoglobulin subclass, recorded sensitivity ranged from 17.0% to 81.9% with best results for immunoglobulin G. Specificity with blood donor sera ranged from 90.2% to 100%, with sera from EBV patients it ranged from 84.3% to 100%. Agreement from fair to nearly perfect was recorded depending on the immunoglobulin class between the assays, the with best results being found for immunoglobulin G. Only for this immunoglobulin class was the association between later sample acquisition times (about three weeks after first positive PCR results) and positive serological results in COVID-19 patients confirmed. In conclusion, acceptable and comparable reliability for the assessed immunoglobulin G-specific assays could be shown, while there is still room for improvement regarding the reliability of the assays targeting the other immunoglobulin classes.


2021 ◽  
Author(s):  
Giuliano Cerasa ◽  
Gabriella Lo Verde

AbstractOzognathus cornutus (LeConte, 1859) (Coleoptera: Ptinidae: Ernobiinae), species native to North America, is a saproxylophagous species and is known to feed on decaying tissues within conspicuous galls and on vegetal decaying organic material such as dried fruits or small wood shavings and insect excrements in galleries made by other woodboring species. A few years after the first record in 2011, its naturalization in Italy is here reported. The insect was found as successor in galls of Psectrosema tamaricis (Diptera Cecidomyiidae), Plagiotrochus gallaeramulorum, Andricus multiplicatus and Synophrus politus (Hymenoptera Cynipidae). The galls seem to have played an important ecological role in speeding up the naturalization process. The lowest proportion of galls used by O. cornutus was recorded for P. tamaricis (23%), the only host belonging to Cecidomyiidae, while the percentages recorded for the other host species, all Cynipidae forming galls on oaks, were higher: 43.6%, 61.1% and 76.9% in A multiplicatus, S. politus and P. gallaeramulorum, respectively. Although O. cornutus is able to exploit other substrates like dried fruits and vegetables, for which it could represent a potential pest, it prefers to live as a successor in woody and conspicuous galls, which thus can represent a sort of natural barrier limiting the possible damages to other substrates.


1997 ◽  
Vol 20 (3) ◽  
pp. 421-423 ◽  
Author(s):  
Ana Maria Waldschmidt ◽  
Tânia Maria Fernandes Salomão ◽  
Everaldo Gonçalves de Barros ◽  
Lúcio de Antônio Oliveira Campos

The objective of the present study was to test three different procedures for DNA extraction of Melipona quadrifasciata based on existing methods for DNA extraction of Apis, plants and fungi. These methods differ in the concentrations of specific substances in the extraction buffer. The results demonstrate that the method used for Apis is not adequate for DNA extraction from M. quadrifasciata. On the other hand, with minor modifications this method and the methods for plants and fungi were adequate for DNA extraction of this stingless bee, both for adults and larvae


Diagnostics ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 36 ◽  
Author(s):  
Sören Hansen ◽  
Marco Roller ◽  
Lamia Alslim ◽  
Susanne Böhlken-Fascher ◽  
Kim Fechner ◽  
...  

The rapid identification of Mycobacterium avium subspecies paratuberculosis (MAP) infected animals within the herd is essential for preventing the spread of the disease as well as avoiding human exposure. Although culture is seen as the gold standard, there are various molecular assays available i.e., polymerase chain reaction (PCR) or isothermal amplification technique (recombinase polymerase amplification (RPA)) for the detection of MAP. The accuracy of the molecular assays is highly dependent on the DNA extraction method. In order to establish a rapid point of need system for the detection of MAP DNA from stool samples, we developed a rapid DNA extraction protocol (MAP DNA SpeedXtract) specified for use in combination with the RPA. The whole procedure from “sample in” to “result out” was conducted in a mobile suitcase laboratory. The DNA extraction is based on reverse purification by magnetic beads, which reduces the required technical demand. The MAP DNA SpeedXtract was performed within 25 min and only three pipetting steps were needed. The amplification and detection time were 20 min in RPA. The sensitivity and specificity of the developed protocol in comparison with the lab-based silica membrane column extraction and real-time PCR were 90.9% (n = 22) and 100% (n = 23), respectively. In conclusion, we established a rapid and reliable protocol for the extraction and detection of MAP DNA. All reagents are cold chain independent. The entire setup is ideal for point of need identification of MAP infected cases.


2018 ◽  
Vol 56 (4) ◽  
Author(s):  
Elitza S. Theel ◽  
D. Jane Hata

ABSTRACT Since the emergence and dissemination of Zika virus (ZIKV) in late 2015, our understanding of the biology, transmission, clinical disease, and potential sequelae associated with infection has markedly expanded. Over the past 2 years, the number of diagnostic assays for ZIKV has increased from none in 2015 to 5 serological assays and 14 molecular assays in 2017, all with emergency use authorization granted through the U.S. Food and Drug Administration. Here we provide an update on ZIKV, addressing what we have collectively learned since the outbreak began, including a summary of currently available diagnostic assays for this virus.


BioTechniques ◽  
2020 ◽  
Vol 68 (5) ◽  
pp. 240-244
Author(s):  
Shan Wei ◽  
Brynn Levy ◽  
Nataly Hoffman ◽  
Claudia Cujar ◽  
Reunet Rodney-Sandy ◽  
...  

Conventional genomic DNA (gDNA) extraction methods can take hours to complete, may require fume hoods and represent the most time-consuming step in many gDNA-based molecular assays. We systematically optimized a bead bashing-based (BBB) approach for rapid gDNA extraction without the need for a fume hood. Human tissue specimens (n = 34) subjected to the 12-min BBB method yielded 0.40 ± 0.17 (mean ± SD) μg of gDNA per milligram of tissue, sufficient for many downstream applications, and 3- and 6-min extensions resulted in an additional 0.43 ± 0.23 μg and 0.48 ± 0.43 μg per milligram of tissue, respectively. The BBB method provides a simple and rapid method for gDNA extraction from mammalian tissue that is applicable to time-sensitive clinical applications.


Pathogens ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 203
Author(s):  
Joanna Dąbrowska ◽  
Jacek Karamon ◽  
Maciej Kochanowski ◽  
Jacek Sroka ◽  
Katarzyna Skrzypek ◽  
...  

Tritrichomonas foetus is described as a pathogen of cattle and cats and also exhibits commensalism with pigs. In order to estimate the prevalence and determine the risk factors for parasite infection, specimens from animal hosts (cat, pigs, and cattle) from Poland were investigated. To our best knowledge, this is the first such study to examine samples from wild boars (Sus scrofa) for the presence of T. foetus. Data were collected from 117 cats, 172 pigs, 236 wild boars, and 180 cattle. The sensitivity of T. foetus identification was increased by using two molecular assays: PCR and loop-mediated isothermal amplification (LAMP). The prevalence of feline tritrichomonosis was 20.51%, and statistically significant differences were obtained between groups of animals regarding age, breed, number of cats, diarrhea, and place of living. Positive PCR and LAMP results for T. foetus were estimated for 16.28% of pigs, and the obtained data were significantly correlated with age. Conversely, no significant differences were observed concerning the farm size factor. In our survey, no cases of bovine tritrichomonosis were found, which is consistent with the data from the other countries of the European Union. Similarly, all wild boar samples were also T. foetus-negative according to LAMP and PCR.


2017 ◽  
Vol 61 (4) ◽  
pp. 427-432 ◽  
Author(s):  
Agnieszka Kędrak-Jabłońska ◽  
Sylwia Budniak ◽  
Marek Krupa ◽  
Anna Szczawińska ◽  
Monika Reksa ◽  
...  

AbstractIntroduction:The aim of the study was the application and comparison of real-time PCR methods based on the fluorescence of SYBR Green I intercalating dye and TaqMan probes for the detection of the 23S rDNA gene ofListeriaspp. and thehlyA gene ofListeria monocytogenesin biological samples of the liver, brain, and blood.Material and Methods:Five strains ofL. monocytogenesand single strains of each speciesL. ivanovii,L. innocua,L. grayi,L. welshimeri,andL. seeligeriwere used for the experiments. Additionally, five strains of other species of bacteria were used for evaluation of the specificity of tests. In the first stage of the study SYBR Green I real-time PCRs, one allowing detection of the 23S rDNA gene and two based on the amplification thehlyA gene, were performed. In the next part, three TaqMan probe-based real-time PCRs allowing confirmation of belonging toListeriaspp. andL. monocytogeneswere conducted.Results:The observation of amplification curves in real-time PCRs enabled the detection of both genes. A high regression coefficient of 0.99 was found for all reactions. Specific amplification products were obtained for the 23S rDNA andhlyA genes which confirm their belonging toListeriaspp. andL. monocytogenes, respectively. Other microbial species did not reveal real-time PCR products.Conclusion:Both real-time PCR methods for the detection ofListeriaspp. andL. monocytogenesin biological samples demonstrated a significant sensitivity and high specificity.


1998 ◽  
Vol 25 (2) ◽  
pp. 147 ◽  
Author(s):  
Nick Dexter ◽  
Paul Meek

The effectiveness of a fox-control exercise at the Beecroft Peninsula, New South Wales, was evaluated by examining the change in proportion of baits taken during free-feeding and after lethal baiting in four different habitats (heath, forest, coastal scrub, beach), and the change in number of radio-collared foxes alive during the course of the baiting exercise. The change in proportion of baits taken by non-target species was also examined over the course of the study. Bait take declined by 97% from the initiation of poison baiting to the final day of poison baiting eight days later with significantly more baits being taken in heath than in any other habitat. Four out of six radio-collared foxes died on the first day of poison baiting while the other two foxes died within ten days of the start of the poison-baiting session. Black rats, currawongs and ravens took a small number of baits throughout the baiting exercise.


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