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Evaluating the Effect of Culture Supernatant of Pseudomonas aeruginosa on Removing the Inhibitory Effect of Heparin in Real-Time PCR Test
2023
Ashrafi, Aysan | Staji, Hamid | Keramati, Keyvan
BACKGROUND: Heparin is a sulfated glycosaminoglycan. Blood is a common source for DNA detection in all kinds of samples, and anticoagulants such as heparin and ethylenediaminetetraacetic acid (EDTA) are used to prevent coagulation. Because heparin has a strong inhibitory effect on polymerase chain reaction (PCR), it is not used in samples that will be tracked by DNA. There are physical, chemical, and enzymatic methods to eliminate the inhibitory effect of heparin on PCR test.OBJECTIVES: First, to compare the intensity of the inhibitory effect of two anticoagulants, heparin, and EDTA, on the Real-Time PCR (qPCR), and then to investigate the impact of the heparinase enzyme present in the medium culture extract of Pseudomonas aeruginosa, on removing the inhibitory effect of heparin during the real-time PCR.METHODS: In the present study, two blood samples containing heparin and EDTA were subjected to a real-time PCR test to check the intensity of the inhibitory effect. Then, the medium culture extract of Pseudomonas aeruginosa was added to the heparinized blood sample infected with Escherichia coli bacteria in two groups with different conditions. In the first group, the DNA in the heparinized blood sample was extracted by the phenol-chloroform isoamyl alcohol method. Then, these samples were incubated with the extract of Pseudomonas aeruginosa bacteria culture medium at different hours, but in the second group, the samples were incubated at different hours before DNA extraction. Also, the DNA concentration in both groups was measured by a Nanodrop device, and finally, all samples were subjected to a real-time PCR test.RESULTS: The results of the research samples showed that although the heparinized blood sample contains more DNA concentration than the EDTA blood sample, it completely prevents genome replication. Also, incubating heparinized blood with Pseudomonas aeruginosa culture medium extract before DNA extraction for more than 24 hours removes the inhibitory effect of heparin during the real-time PCR, even at a lower cycle threshold than the EDTA-containing sample.CONCLUSIONS: The Pseudomonas aeruginosa culture medium extract may enable researchers to use heparinized blood samples for genome amplification and diagnosis without using expensive and limited commercial heparinase enzyme.
اظهر المزيد [+] اقل [-]Monitored therapy of sporadic mycobacteriosis caused by Mycobacterium genavense in Atlantic canaries (Serinus canaria) and Bengalese finch (Lonchura striata)
2021
Ledwoń, Aleksandra | Dolka, Izabella | Adamczyk, Krzysztof | Szeleszczuk, Piotr
Mycobacteriosis is a significant disease of companion and wild birds which causes emaciation and widely distributed lesions, as well as being a potential zoonosis. Its primary aetiological agents in birds are Mycobacterium avium subsp. avium and the fastidious Mycobacterium genavense. This study monitored the therapy of birds naturally infected with Mycobacterium genavense to gain understanding of its effectiveness and the interrelation of co-infections with the disease course and pharmacotherapy. Five Atlantic canaries (Serinus canaria) and one Bengalese finch (Lonchura striata) with tentative diagnoses of mycobacteriosis resulting from M. genavense infection were treated twice daily with clarithromycin at 40 mg/kg, ethambutol at 30 mg/kg, and moxifloxacin at 10 mg/kg for 6 months. Two canaries were also found to be carriers of Cryptosporidium galli. Mycobacteria in faecal samples of all birds were investigated by bacterioscopy and quantitative PCR. Molecular tests yielded positive results for up to four months after treatment initiation for M. genavense and Cryptosporidium, but microscopy failed to detect the latter after four weeks in specimens from one canary. Co-infections with polyomavirus (in all birds) and circovirus and bornavirus (in canaries) were diagnosed. Two birds died during treatment and one was euthanised because of other disease, 1 month after treatment completion. Three canaries were in relatively good health a year after treatment. Canary circovirus and polyomavirus co-infection may suppress the immune system and this may facilitate the development of mycobacteriosis. The set of drugs used led to the complete cure of mycobacteriosis in three canaries. In one bird the disease returned. Clarithromycin was the active drug against C. galli. Molecular methods serve well to monitor mycobacteriosis therapy and identify M. genavense and C. galli carriage.
اظهر المزيد [+] اقل [-]Prevalence of Toxoplasma gondii in retail fresh meat products from free-range chickens in Spain
2021
Salinas María Jesús Gracia | Campos Cristina Escolano | Peris María Paz Peris | Kassab Nabil Halaihel
Toxoplasma gondii is one of the most prevalent zoonotic protozoan parasites worldwide and affects the vast majority of warm-blooded animal species, including humans. Postnatal infection in humans occurs through the ingestion of sporulated T. gondii oocysts or via the oral intake of parasite tissue cysts during the consumption of raw or undercooked meat. In this regard, given their high exposure to oocysts, chickens (Gallus domesticus) raised on the ground constitute a potential source of T. gondii.
اظهر المزيد [+] اقل [-]Monitored therapy of sporadic mycobacteriosis caused by Mycobacterium genavense in Atlantic canaries (Serinus canaria) and Bengalese finch (Lonchura striata)
2021
Ledwoń Aleksandra | Dolka Izabella | Adamczyk Krzysztof | Szeleszczuk Piotr
Mycobacteriosis is a significant disease of companion and wild birds which causes emaciation and widely distributed lesions, as well as being a potential zoonosis. Its primary aetiological agents in birds are Mycobacterium avium subsp. avium and the fastidious Mycobacterium genavense. This study monitored the therapy of birds naturally infected with Mycobacterium genavense to gain understanding of its effectiveness and the interrelation of co-infections with the disease course and pharmacotherapy.
اظهر المزيد [+] اقل [-]TaqMan real-time PCR for detection of pathogenic Leptospira spp. in canine clinical samples
2023
Rahman Mohammad Sabri Abdul | Khor Kuan Hua | Khairani-Bejo Siti | Lau Seng Fong | Mazlan Mazlina | Roslan Mohd Azri | Ajat Mohd Mokrish Md | Noor Mohd Akmal Mohd
Canine leptospirosis has always been a differential diagnosis in dogs presenting with clinical signs and blood profiles associated with kidney and/or liver disease. The conventional polymerase chain reaction (PCR) provides diagnoses, but real-time PCR-based tests provide earlier confirmation and determine the severity of infection, especially in the acute stage, allowing early detection for immediate treatment decisions. To our knowledge, real-time PCR has not been routinely adopted for clinical investigation in Malaysia. This study evaluated TaqMan real-time PCR (qPCR) assays diagnosing leptospirosis and compared their applicability to clinical samples from dogs with kidney and/or liver disease against a conventional PCR reference.
اظهر المزيد [+] اقل [-]Prevalence of Toxoplasma gondii in retail fresh meat products from free-range chickens in Spain
2021
Salinas, María Jesús Gracia | Campos, Cristina Escolano | Peris, María Paz Peris | Kassab, Nabil Halaihel
Toxoplasma gondii is one of the most prevalent zoonotic protozoan parasites worldwide and affects the vast majority of warm-blooded animal species, including humans. Postnatal infection in humans occurs through the ingestion of sporulated T. gondii oocysts or via the oral intake of parasite tissue cysts during the consumption of raw or undercooked meat. In this regard, given their high exposure to oocysts, chickens (Gallus domesticus) raised on the ground constitute a potential source of T. gondii. For the first time in Spain, a survey was undertaken in commercial retail free-range poultry. A total of 50 thighs from different animals were analysed. The samples were homogenised and an acid pepsin digestion procedure was applied prior to molecular analysis. Toxoplasma gondii DNA was isolated from meat by qPCR. Two sets of primers were used for DNA amplification targeting the specific sequence of a 529 bp repeat element and another set of primers was utilised for the surface antigen protein-1 gene. DNA extracted from 5 out of 50 tissue samples was positive for both genes by qPCR amplification. The 10% prevalence of Toxoplasma infection found in commercial free-range chickens raises public health issues.
اظهر المزيد [+] اقل [-]Comparison of three nucleic acid-based tests for detecting <i>Anaplasma marginale</i> and <i>Anaplasma centrale</i> in cattle
2017
Mamohale E. Chaisi | Janine R. Baxter | Paidashe Hove | Chimvwele N. Choopa | Marinda C. Oosthuizen | Kelly A. Brayton | Zamantungwa T.H. Khumalo | Awelani M. Mutshembele | Moses S. Mtshali | Nicola E. Collins
Several nucleic acid-based assays have been developed for detecting Anaplasma marginale and Anaplasma centrale in vectors and hosts, making the choice of method to use in endemic areas difficult. We evaluated the ability of the reverse line blot (RLB) hybridisation assay, two nested polymerase chain reaction (nPCR) assays and a duplex real-time quantitative polymerase chain reaction (qPCR) assay to detect A. marginale and A. centrale infections in cattle (n = 66) in South Africa. The lowest detection limits for A. marginale plasmid DNA were 2500 copies by the RLB assay, 250 copies by the nPCR and qPCR assays and 2500, 250 and 25 copies of A. centrale plasmid DNA by the RLB, nPCR and qPCR assays respectively. The qPCR assay detected more A. marginale- and A. centrale-positive samples than the other assays, either as single or mixed infections. Although the results of the qPCR and nPCR tests were in agreement for the majority (38) of A. marginale-positive samples, 13 samples tested negative for A. marginale using nPCR but positive using qPCR. To explain this discrepancy, the target sequence region of the nPCR assay was evaluated by cloning and sequencing the msp1β gene from selected field samples. The results indicated sequence variation in the internal forward primer (AM100) area amongst the South African A. marginale msp1β sequences, resulting in false negatives. We propose the use of the duplex qPCR assay in future studies as it is more sensitive and offers the benefits of quantification and multiplex detection of both Anaplasma spp.
اظهر المزيد [+] اقل [-]EXPRESSION PROFILE OF EARLY PREGNANCY MARKER GENES (OAS-1 AND MX-2) AND SERUM CONCENTRATION OF MX-2 PROTEIN IN JERSEY CROSSBRED COWS
2023
A.G. Nithin | T. Sarath | K. Vijayarani | K. Krishnakumar | N. Arunmozhi | C. Pugazharasi
In the present study, the expression pattern of OAS-1 and MX-2 gene in peripheral blood mononuclear cells (PBMC) was associated with the early pregnancy in cattle. A total of 60 animals were selected and divided into 2 groups, treatment (50) and control (10) group and synchronized using double PGF2α protocol by 11 days apart followed by insemination at 72 and 96 hrs after second dose of PGF2α. The cows were subjected to blood collection on day 0, 14, 18, 20 and 25 post insemination and Peripheral Blood Mononuclear Cells (PBMC) were harvested using Histopaque® solution, followed by RNA isolation and cDNA synthesis. A significantly (P≤0.01) higher expression of OAS-1 and MX-2 gene was observed on days 18 and 20 post oestrum by quantitative real-time PCR and concentration of MX-2 protein in serum were significantly higher (P≤0.05) on day 18, 20 and 25 in pregnant cows when compared with that of non-pregnant cows. Hence, the present study is concluded that the expression of OAS-1 and MX-2 genes and their encoded proteins may be used to develop a marker for early pregnancy diagnosis in cattle.
اظهر المزيد [+] اقل [-]Cães naturalmente infectados por Rangelia vitalii, Babesia canis vogeli, e Ehrlichia canis em São Paulo, Brasil
2023
Thais Fernandes Batista | Adriana Cortez | Marcelo Bahia Labruna | Daniel Pedro Barbosa Nascimento | Ricardo Duarte Lopes | Jonas Moraes Filho
As hemoparasitoses em cães podem ser causadas por diversos agentes, sendo essas doenças transmitidas por artrópodes hematófagos. Esses agentes podem causar diversas manifestações clínicas e, em alguns casos, podem matar o hospedeiro. Este estudo teve como objetivo detectar por PCR em tempo real a frequência de Ehrlichia canis, Rickettsia rickettsii, Anaplasma platys, Rangelia vitalii e Babesia canis vogeli em amostras de cães da zona sul da cidade de São Paulo, Brasil. Das 98 amostras de cães, 18 (18,4%) testaram positivo com reação em cadeia da polimerase em tempo real para pelo menos um agente estudado. Destas 18 amostras, 17 testaram positivo para um único agente (11,2% para B. canis vogeli, 1,02% para R. vitalii e 5,1% para E. canis), e uma apresentou coinfecção com B. canis vogeli e R. vitalii. Os resultados demonstram a presença de hemoparasitas nos animais estudados, o que pode influenciar a qualidade e a expectativa de vida desses animais. Além disso, é o primeiro relato da detecção de R. vitalli na zona sul de São Paulo e serve de alerta para os clínicos de pequenos animais incluírem esse agente como diagnóstico diferencial para as hemoparasitoses.
اظهر المزيد [+] اقل [-]Serological survey of Rickettsia in equids from Vale do Paraíba, São Paulo, Brazil, and their tick identification and molecular investigation of Rickettsia
2019
Claudia Iorio Budweg | Amanda Oliveira de Sousa | Tânia Regina Vieira de Carvalho | Zahi Êni Santos Souza | Maria Carolina de Azevedo Serpa | Thiago Fernandes Martins | Fernanda Nieri-Bastos | Arlei Marcili | Marcelo Bahia Labruna | Jonas Moraes-Filho
Brazilian spotted fever is a serious and lethal illness for humans and is caused by the Rickettsia rickettsii bacteria. In the state of São Paulo/SP (Brazil), the etiological agent of this disease is transmitted by the Amblyomma sculptum tick. It was already shown that horses infected with this bacteria produce a strong immune response and could be important sentinels for the detection of the disease in a proper region. The present investigation performed a serological survey in horses from five farms of Vale do Paraíba, São Paulo state, Brazil, searching for antibodies against, Rickettsia rickettsii, Rickettsia parkeri, Rickettsia amblyommatis, Rickettsia rhipicephali, and Rickettsia bellii. In each farm, ticks were also collected that were taxonomically identified and examined by real-time PCR for Rickettsia spp DNA. Blood samples were collected from 206 horses, and 334 ticks were picked up from these animals from January to December 2017. Eighty ticks were A. sculptum and 254 Dermacentor nitens. Of the blood samples, 7.3% seroconverted to Rickettsia spp. Of these, 0.97% had a positive serological response to R. bellii. None of the 80 A. sculptum ticks were positive through real-time PCR for Rickettsia spp. Although there was no detection of ticks infected by Rickettsia spp in five farms of Paraíba Valley, the horses presented serological positive reactions against this agent. Thus, further large studies should be conducted in the area targeting hosts and vectors to generate data for control measures of the transmission of Brazilian spotted fever.
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