scholarly journals Molecular Characterization of Clostridium perfringens Strains Isolated in Italy

Toxins ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 650
Author(s):  
Katia Forti ◽  
Laura Ferroni ◽  
Martina Pellegrini ◽  
Deborah Cruciani ◽  
Antonio De Giuseppe ◽  
...  
Keyword(s):  
Animal Species ◽  
Food Samples ◽  
Type B ◽  
Chain Reaction ◽  
Type D ◽  
Wide Range ◽  
Enteric Infections ◽  
Type C ◽  
Polymerase Chain

Clostridium (C.) perfringens is the causative agent of several diseases and enteric infections in animals and humans. The pathogenicity of the bacterium is largely mediated by the production of a wide range of toxins. Individual C. perfringens strains produce only subsets of this toxin repertoire, which permits the classification in seven toxinotypes (A–G). In addition, a variety of minor toxins further characterizes the single strains. The aim of this work was to evaluate, using Polymerase Chain Reaction (PCR) assays, the diversity of 632 C. perfringens strains isolated in Italy over 15 years. The genotyped strains were analyzed to determine the presence of major and minor toxins (cpe, consensus, and atypical cpb2), their geographical origins, and the source of isolation (animal species or food). Our study shows that toxinotype A had the greatest representation (93%) and correlated mainly with consensus cpb2 in a variety of animal species, as well as with atypical cpb2 in the five food samples. Type D, associated with cpe and atypical cpb2 minor toxins, was identified in 3% of the cases, and type F was identified in 2.5%. Seven type C isolates (1.1%) were detected in cattle, whereas the only type B atypical cpb2 isolated in Italy was detected in a goat, and one type E cpe+atypical cpb2 was detected in a sheep. Type G was not detected.

scholarly journals Characterization of a new human apolipoprotein A-I Yame by direct sequencing of polymerase chain reaction-amplified DNA.

1991 ◽  
Vol 32 (8) ◽  
pp. 1275-1280
Author(s):  
Y Takada ◽  
J Sasaki ◽  
M Seki ◽  
S Ogata ◽  
Y Teranishi ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Direct Sequencing ◽  
Chain Reaction ◽  
Human Apolipoprotein ◽  
Apolipoprotein A ◽  
Polymerase Chain

scholarly journals Characterization of Xanthomonas axonopodis pv. phaseoli isolates

2008 ◽  
Vol 34 (3) ◽  
pp. 228-231 ◽  
Author(s):  
Willian Mário de Carvalho Nunes ◽  
Maria Júlia Corazza ◽  
Silvana Aparecida Crestes Dias de Souza ◽  
Siu Mui Tsai ◽  
Eiko Eurya Kuramae
Keyword(s):  
Xanthomonas Campestris ◽  
Random Amplified Polymorphic Dna ◽  
Hypersensitive Reaction ◽  
Chain Reaction ◽  
Xanthomonas Axonopodis ◽  
Paulo State ◽  
Total Dna ◽  
Polymerase Chain ◽  
Bacterial Plant Pathogen

A simple, quick and easy protocol was standardized for extraction of total DNA of the bacteria Xanthomonas axonopodis pv. phaseoli. The DNA obtained by this method had high quality and the quantity was enough for the Random Amplified Polymorphic DNA (RAPD) reactions with random primers, and Polymerase Chain Reaction (PCR) with primers of the hypersensitivity and pathogenicity gene (hrp). The DNA obtained was free of contamination by proteins or carbohydrates. The ratio 260nm/380nm of the DNA extracted ranged from 1.7 to 1.8. The hrp gene cluster is required by bacterial plant pathogen to produce symptoms on susceptible hosts and hypersensitive reaction on resistant hosts. This gene has been found in different bacteria as well as in Xanthomonas campestris pv. vesicatoria (9). The primers RST21 and RST22 (9) were used to amplify the hrp gene of nine different isolates of Xanthomonas axonopodis pv. phaseoli from Botucatu, São Paulo State, Brazil, and one isolate, "Davis". PCR amplified products were obtained in all isolates pathogenic to beans.

Characterization of Giardia duodenalis by polymerase-chain-reaction fingerprinting

1998 ◽  
Vol 84 (9) ◽  
pp. 707-714 ◽  
Author(s):  
Wieger L. Homan ◽  
Margriet Gilsing ◽  
Hafida Bentala ◽  
Louis Limper ◽  
Frans van Knapen
Keyword(s):  
Polymerase Chain Reaction ◽  
Giardia Duodenalis ◽  
Chain Reaction ◽  
Polymerase Chain

scholarly journals Rhodococcus equi Infections in Goats: Characterization of Virulence Plasmids

2017 ◽  
Vol 55 (2) ◽  
pp. 273-276 ◽  
Author(s):  
Lauren W. Stranahan ◽  
Quinci D. Plumlee ◽  
Sara D. Lawhon ◽  
Noah D. Cohen ◽  
Laura K. Bryan
Keyword(s):  
Polymerase Chain Reaction ◽  
Lymph Nodes ◽  
Rhodococcus Equi ◽  
Caseous Lymphadenitis ◽  
Chain Reaction ◽  
Disseminated Infection ◽  
Virulence Plasmids ◽  
Visceral Organs ◽  
Polymerase Chain

Rhodococcus equi is an uncommon cause of systemic pyogranulomatous infections in goats with macroscopic similarities to caseous lymphadenitis caused by Corynebacterium pseudotuberculosis. Caprine cases have previously been reported to be caused by avirulent R. equi strains. Six cases of R. equi infection in goats yielding 8 R. equi isolates were identified from 2000 to 2017. Lesions varied from bronchopneumonia, vertebral and humeral osteomyelitis, and subcutaneous abscesses, to disseminated infection involving the lungs, lymph nodes, and multiple visceral organs. Isolates of R. equi from infected goats were analyzed by polymerase chain reaction for R. equi virulence-associated plasmid ( vap) genes. Seven of 8 isolates carried the VapN plasmid, originally characterized in bovine isolates, while 1 isolate lacked virulence plasmids and was classified as avirulent. The VapN plasmid has not been described in isolates cultured from goats.

scholarly journals Molecular typing of Clostridium perfringens isolated from swine in slaughterhouses from São Paulo State, Brazil

2012 ◽  
Vol 42 (8) ◽  
pp. 1450-1456 ◽  
Author(s):  
Thais Sebastiana Porfida Ferreira ◽  
Andrea Micke Moreno ◽  
Renata Rodrigues de Almeida ◽  
Cleise Ribeiro Gomes ◽  
Debora Dirani Sena de Gobbi ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Clostridium Perfringens ◽  
Food Poisoning ◽  
Positive Bacterium ◽  
Chain Reaction ◽  
High Prevalence ◽  
Fecal Isolate ◽  
Finishing Pig ◽  
Type C ◽  
Polymerase Chain

Clostridium perfringens is an anaerobic Gram-positive bacterium known as common pathogen for humans, for domestic and wildlife animals. Although infections caused by C. perfringens type C and A in swine are well studied, just a few reports describe the genetic relationship among strains in the epidemiological chain of swine clostridioses, as well as the presence of the microorganism in the slaughterhouses. The aim of the present study was to isolate C. perfringens from feces and carcasses from swine slaughterhouses, characterize the strains in relation to the presence of enterotoxin, alpha, beta, epsilon, iota and beta-2 toxins genes, using polymerase chain reaction (PCR) and comparing strains by means of Pulsed field gel electrophoresis (PFGE). Clostridium perfringens isolation frequencies in carcasses and finishing pig intestines were of 58.8% in both types of samples. According to the polymerase chain reaction assay, only alfa toxin was detected, being all isolates also negative to enterotoxin and beta2 toxin. Through PFGE technique, the strains were characterized in 35 pulsotypes. In only one pulsotype, the isolate from carcass sample was grouped with fecal isolate of the same animal, suggesting that the risk of cross-contamination was low. Despite the high prevalence of C. perfringens in swine carcasses from the slaughterhouses assessed, the risk of food poisoning to Brazilian pork consumers is low, since all strains were negative to cpe-gene, codifying enterotoxin.

Kato–Katz thick smears as a DNA source of soil-transmitted helminths

2018 ◽  
Vol 94 ◽  
Author(s):  
K.J.L. Monteiro ◽  
D.A. Calegar ◽  
F.A. Carvalho-Costa ◽  
L.H. Jaeger ◽  
Keyword(s):  
Evolutionary Genetics ◽  
Large Collection ◽  
Chain Reaction ◽  
Rural Regions ◽  
Dna Recovery ◽  
Polymerase Chain ◽  
N 93 ◽  
Initial Processing ◽  
Specific Species

AbstractDespite the reduction in the prevalence of soil-transmitted helminthiases in many regions of the world, morbidity rates remain high in some rural regions. The Kato–Katz technique is a simple, inexpensive and field-applicable tool commonly used for the diagnosis and worm-burden characterization of these infections. Molecular studies have revolutionized our understanding of the epidemiology and evolutionary genetics of parasites. In this study we recovered helminthic DNA from Kato–Katz slides (n = 93) prepared in 2011 in the Brazilian Amazon. We achieved DNA recovery by polymerase chain reaction (PCR) in 84% of cases for Ascaris sp. and 75% of cases for hookworms. The sequencing confirmed the specific species of the amplicons. The slides stored for a few years could be analysed using this methodology, allowing access to DNA from a large collection of samples. We must consider the Kato–Katz thick smears as a source of helminth DNA. This can significantly reduce logistical difficulties in the field in terms of obtaining, preserving, transporting and initial processing of samples.

scholarly journals Comparative Study of Immune-Diagnostic Tools with Polymerase Chain Reaction in Sub-Clinical Leishmaniasis Isolates

2011 ◽  
Vol 12 (1) ◽  
pp. 34-39 ◽  
Author(s):  
Nazar M Abdalla
Keyword(s):  
Polymerase Chain Reaction ◽  
Skin Test ◽  
Diagnostic Methods ◽  
Diagnostic Tools ◽  
Enzyme Linked Immunosorbent Assay ◽  
Clinical Form ◽  
Chain Reaction ◽  
Leishmanin Skin Test ◽  
Wide Range ◽  
Polymerase Chain

Objective: This study aimed to identify cases of leishmaniasis in the Nuba Mountain area, which is situated in a unique geographical site located in the centre of Sudanese leishmania belt. Wide range of investigations are available for detection of leishmania cases, but still the most reliable and easy test used as screening and epidemiological tool in field studies needs to be evaluated. The most commonly used conventional diagnostic methods direct microscopy and culture have some drawbacks in diagnosing subclinical cases of leishmaniasis. Materials and methods: In this study, comparative properties of various immune-diagnostic tools with Polymerase Chain Reaction used in sub-clinical leishmaniasis isolates were explored. The immune-diagnostic tools involved in this study include- Leishmanin Skin Test (LST), Enzyme Linked Immunosorbent Assay (ELISA) and Direct Agglutination Test (DAT). The study was conducted in the Green Valley village (Rashad Province, South Kordofan State) with a population of 332. Most of the villagers presented with sub-clinical form of leishmaniasis with minor symptoms and signs without the features found in clinical form of visceral leishmaniasis such as fever, diarrhoea, epistaxis, enlarged lymph nodes, spleen and liver. In this study we collected demographic, clinical and epidemiological data using special questionnaire. Leishmanin skin test (LST), ELISA, DAT and PCR for parasite DNA detection were used. Result: The final positive cases detected by PCR were 32 out of 332 belong to L. donovani species. The final positive cases detected by LST were 51.2% of the total population under study, while 11 out of the 37 tested samples were positive by ELISA. All of the 332 villagers showed negative readings by DAT with exception of three individuals who were positive with very high titers. Conclusion: DNA etxtraction and amplification with primers can be a good screening tool in subclinical leishmaniasis isolates. Keyword: Sub-clinical; Leishmaniasis; Leishmanin Skin Test; ELISA; DAT; PCR. DOI: 10.3329/jom.v12i1.5422J Medicine 2011; 12 : 34-39

scholarly journals The effectiveness of TiO2 additions to mortar to maintain initial conditions in terms of its reflectance to solar radiation

2017 ◽  
Vol 17 (3) ◽  
pp. 39-56 ◽  
Author(s):  
Sérgio Roberto Andrade Dantas ◽  
Fulvio Vittorino ◽  
Kai Loh
Keyword(s):  
Solar Radiation ◽  
Ultraviolet Radiation ◽  
Initial Conditions ◽  
Type A ◽  
Just Noticeable Difference ◽  
Type B ◽  
Climate Conditions ◽  
Type D ◽  
Type C ◽  
Over Time

Abstract Contact of facades with degradation agents and direct incidence of ultraviolet radiation on external coatings make them more opaque over time, affecting their colour and reflectance characteristics. This study evaluated the effect of adding different TiO2 contents to mortars applied in concrete substrates in order to verify the reflectance maintenance on surfaces after exposure over time. Mortar with different concentrations of TiO2 (1%, 5%, 10%) were produced in relation to the total dry premix, added as a powder and compared to unpainted mortar without TiO2 (type "A") and painted mortar without TiO2 (type "B"), both used as a reference for colour and reflectance. Exposed over 16 months to climate conditions in São Paulo, regarding the maintenance of reflectance and solar radiation, the results showed that type "B" (0%TiO2) painted mortar presented the best performance. Type "C" (1%TiO2) and type "D" (5%TiO2) unpainted mortar remained more stable. Type "A" (0%TiO2) and type "E" (10%TiO2) unpainted mortar showed greater differences according to the Just Noticeable Difference (JND) range caused by dirt pick up.

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