A technique for the amplification of very small quantities of cDNA based on a semi-nested polymerase chain reaction system has been developed. The technique uses an additional blocking oligonucleotide "primer" in the second round nest which is complementary to one of the first round primers. This prevents amplification of first round product or of any other unwanted products dependent on that p...

In this study, 331 samples from calves less than one month old from a dairy herd in the district of Piracanjuba, state of Goiás, Brazil were tested for rotavirus. Thirty-three samples (9.9%) tested positive for rotavirus. Out of those, 31 were submitted to G and P characterization by reverse transcription followed by semi-nested polymerase chain reaction. Two samples were characterized as G6P[1...

Magellanic penguins (Spheniscus magellanicus) are native to Argentina, Chile and the Falkland Islands. Magellanic penguins are highly susceptible to blood parasites such as the mosquito-borne Plasmodium spp., which have been documented causing high morbidity and mortality in zoos and rehabilitation centres. However, to date no blood parasites have been detected in wild Magellanic penguins, and ...

OBJECTIVE To determine the prevalence of the Torque teno virus in healthy donors in the northern and northwestern regions of the state of Paraná, southern Brazil. METHODS The Torque teno virus was detected by a nested polymerase chain reaction using a set of oligoprimers for the N22 region. RESULTS The prevalence of the virus was 69% in 551 healthy blood donors in southern Brazil. There was...

Using nested polymerase chain reaction, we sequenced Dobrava virus (DOB) from the rodent Apodemus agrarius in Hungary. The samples we isolated group with DOB samples previously isolated from A. flavicollis. This grouping may indicate host switching.

We have modified an existing semi-nested multiplex polymerase chain reaction (PCR) by adding one Plasmodium knowlesi-specific nested PCR, and validated the latter against laboratory and clinical samples. This new method has the advantage of being relatively affordable in low resource settings while identifying the five human Plasmodium species with a three-step PCR.

bovine viral diarrhoea virus (bvdv) is an important pathogen of dairy cattle. in this study, bulk milk samples representing a total of 4105 milking cows, from 18 dairy cattle herds in the suburb of mashhad- iran, were tested for presence of bvdv by the use of a nested reverse transcription polymerase chain reaction (nested rt- pcr) assay. non of the cows in the herds had been vaccinated against...

invasive aspergillosis (1 is a life-threatening condition in immunocompromised patients. an early diagnosis is of great importance because early treatment may resolve this potentially fatal infection. recently, the polymerase chain reaction (pcr) has been used successfully in detecting specific dna of several pathogen. in this study, nested pcr was used to detect dna specific for a!.pergiflus s...

background and aims: canine distemper (cd) is a deadly infectious disease of canidae family. cd is a multi-systemic viral disease and is specified by wide range of clinical symptoms. the manifestations are not always indicative of cd, therefore a laboratory confirmation is necessary for suspected cases. materials and methods: different clinical specimens of 19 cd suspected unvaccinated dogs wer...