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Multiplex polymerase chain reaction assay for genotyping Clostridium perfringens.
1997
Meer R.R. | Songer J.G.
Blood type AB in the feline AB blood group system.
1996
Griot Wenk M.E. | Callan M.B. | Casal M.L. | Chisholm Chait A. | Spitalnik S.L. | Patterson D.F. | Giger U.
Prevalence of four enterotoxin (STaP, STaH, STb, and LT) and four adhesin subunit (K99, K88, 987P, and F41) genes among Escherichia coli isolates from cattle.
1990
Mainil J.G. | Bex F. | Jacquemin E. | Pohl P. | Couturier M. | Kaeckenbeeck A.
Colony hybridizations with DNA probes for 3 heat-stable (STaP, STaH, and STb) enterotoxins and 1 heat-labile (LT) enterotoxin and for 4 adhesins (K99, F41, K88, 987P) were performed on 870 Escherichia coli isolates to determine pathotypes prevalent among enterotoxigenic E coli (ETEC) isolated from cattle in Belgium. One hundred thirty-two E coli isolates (15.2%) hybridized with probes STaP, K99, and/or F41. The 5 other probes were not hybridized by E coli isolates. Therefore, only STaP enterotoxin and K99 and F41 adhesins were virulence factors of ETEC isolated from cattle. Two major pathotypes accounted for 95% of the ETEC: STaP+K99+F41+ (67.4%) and STaP+K99+ (27.3%). The last 5% of probe-positive isolates had STaP+, STaP+F41+, or K99+F41+ minor pathotypes. Of 12 American ETEC isolates also assayed, 7 were positive with STb and/or 987P probes (pathotypes STaP+STb+,STaP+ 987P+, or STaP+STb+987P+) and may be porcine- rather than bovine-specific enteropathogens. The remaining 5 American ETEC isolates belonged to 3 minor pathotypes (STaP+,STaP+F41+, and K99+F41+) also found among Belgian E coli isolates. Such isolates may be derivatives of STaP+K99+F41+ or STaP+K99+ ETEC after in vivo or in vitro loss of virulence genes and/or non-ETEC isolates, which have acquired virulence genes by in vivo transfer.
Afficher plus [+] Moins [-]Association between the effacing (eae) gene and the Shiga-like toxin-encoding genes in Escherichia coli isolates from cattle.
1993
Mainil J.G. | Jacquemin E.R. | Kaeckenbeeck A.E. | Pohl P.H.
Two hundred ninety-six Eschericbia coli isolates from feces or intestines of calves with diarrhea were hybridized with 7 gene probes. One probe (the eae probe) was derived from the eae gene coding for a protein involved in the effacement of the enterocyte microvilli by the group of bacteria called attaching and effacing E coli (AEEC), and 2 probes were derived from genes coding for the Shiga-like toxins (SLT) 1 and 2 produced by the verocytotoxic E coli (VTEC). The other 4 probes were derived from DNA sequences associated with the adhesive properties of enteroadherent E coli (EAEC) to cultured cells (the EAF probe for the localized adherence pattern, probes F1845 and AIDA-1 for the diffuse adherence pattern, and the Agg probe for the aggregative adherence pattern). Hybridization results for the eae probe were in agreement, for all but 1 of the 8 isolates, with previously published phenotypic results of microvilli effacement. The latter was previously reported as effacing the microvilli of calf enterocytes, but was eae probe-negative. Two classes of isolates hybridized with the eae probe. Members of a first class (60 isolates) additionally produced a positive signal with 1 or both of the SLT probes (VTEC-AEEC isolates). Isolates hy- bridizing with the eae and the SLT1 probes were the most frequent: 56 isolates (ie, 93% of all VTEC-AEEC). Members of the second class (10 isolates) failed to hybridize with either SLT probe (non-VTEC-AEEC isolates). Most isolates of these 2 classes belong to only 4 serogroups: O5, O26, O111, and O118. In addition to these 2 AEEC classes, a VTEC class (20 isolates) was observed. Such isolates were positive with 1 or both SLT probes, but were negative with the eae probe. All but 1 isolate belonged to serogroups not found among the AEEC isolates. Only 7 of all AEEC and VTEC isolates were positive with the EAF, the F1845, or the AIDA-1 probe, and none were positive with the Agg probe. On the other hand, 32 non-VTEC, non-AEEC isolates were po.
Afficher plus [+] Moins [-]Second-generation pseudorabies virus vaccine with deletions in thymidine kinase and glycoprotein genes.
1987
Kit S. | Sheppard M. | Ichimura H. | Kit M.
Clinicopathological analysis of expression of enhancer of zeste homologue 2 in canine mammary carcinoma
2022
Ren, Xiaoli | Fan, Yuying | Li, Yongqi | Shi, Dongmei | Liu, Yun
Enhancer of zeste homologue 2 (EZH2) is the human homologue of Drosophila zeste gene enhancer. The aim of this study was to determine the expression of EZH2 in canine mammary carcinomas (CMCs) and its relationship with clinicopathological features. The expression of EZH2 mRNA and protein in 53 CMC tissue and 8 normal mammary gland tissue samples was measured by quantitative real-time PCR and immunohistochemical staining assay, respectively. The relationship between EZH2 protein expression and clinicopathological features was analysed by χ2 test to further explore the clinical significance of EZH2 in CMCs. Compared with normal mammary gland tissues, EZH2 mRNA expressions were significantly increased in CMC tissues (P < 0.01). Moreover, normal mammary glands did not express the EZH2 protein but carcinomic glands did, and expression increased in CMCs with high histological grades, especially in histological grade II (P < 0.05). However, EZH2 expression was not related to age, tumour size, or metastasis (P > 0.05). The expression of EZH2 in one type of CMC was not significantly different from the expression in any other type (P > 0.05). EZH2 is highly expressed in CMCs, indicating that it can be used as a molecular marker for early diagnosis, prognosis, or therapy of CMCs.
Afficher plus [+] Moins [-]Occurrence of Ornithobacterium rhinotracheale in Polish turkey flocks
2022
Kursa, Olimpia | Tomczyk, Grzegorz | Sawicka-Durkalec, Anna
Ornithobacterium rhinotracheale (ORT) causes significant economic losses to the poultry industry around the world. The bacterium often affects poultry as part of multiple infections causing very serious clinical signs that are usually not limited only to the respiratory system. This study’s main objective was the retrospective detection and identification of ORT in turkey flocks. ORT identification was performed in 6,225 samples taken from 133 different flocks between 2015 and 2020. Molecular methods were used, specifically real-time PCR and traditional PCR. We focused on partial 16S rRNA gene sequences of isolates, which were compared with sequences obtained from GenBank. The reaction products were analysed phylogenetically. Molecular methods indicating secondary infections was carried out, and the bacterial composition of the upper respiratory tract was 16S metasequenced for selected flocks to identify any other pathogens. The presence of ORT was detected in 30.83% of samples by real-time PCR and 28.57% by PCR. Phylogenetic analysis of the PCR products from the turkeys samples showed that their sequences resolved into two main genetic groups. Tests for the occurrence of secondary infections showed the presence of Mycoplasma gallisepticum and M. synoviae in some samples but the total absence of Bordetella avium. The upper respiratory tract in turkeys was dominated by two major phyla Firmicutes and Proteobacteria. At the genus level, the genera Ornithobacterium, Mycoplasma, Gallibacterium, Avibacterium, and Escherichia-Shigella were found which may include pathogenic bacteria that can cause clinical symptoms. The results of the analysis of multiple infection carried out in flocks with respiratory signs are probably associated with outbreaks of ornithobacteriosis in turkey flocks in Poland.
Afficher plus [+] Moins [-]A new enzyme-linked immunosorbent assay for serological diagnosis of seal parapoxvirus infection in marine mammals
2022
Badr, Yassien | Rahman, Md Matiur | Ōno, Yoshito | Ishijima, Keita | Maeda, Ken | Kohyama, Kaoru | Kamatari, Yuji O. | Shimizu, Kaori | Okada, Ayaka | Inoshima, Yasuo
Seal parapoxvirus (SPPV) infection has been reported among pinnipeds in aquaria in Japan; however, its seroprevalence is unknown. Therefore, an enzyme-linked immunosorbent assay (ELISA) was developed for serological diagnosis of SPPV infection. The gene encoding the major envelope protein of SPPV was cloned into the eukaryotic expression vector pAcGFP1-N1, which encodes the green fluorescence protein (GFP), thereby producing a fusion protein (Env-GFP). Parental and cloned vector DNA was independently transfected into cultured seal cells for the expression of GFP and Env-GFP. The wells of an ELISA plate were coated with either GFP- or Env-GFP-transfected cell lysates. The light absorbance of each serum sample was adjusted by subtracting the absorbance of GFP-coated wells from that of Env-GFP-coated wells. Sera from two spotted seals (Phoca largha), six beluga whales (Delphinapterus leucas), three Pacific white-sided dolphins (Lagenorhynchus obliquidens), and ten bottlenose dolphins (Tursiops truncatus) from an aquarium in Japan were examined using the ELISA. Positive reactions were not observed, except in one preserved sample collected ten years ago from a naturally SPPV-infected spotted seal. The established ELISA could be useful in screening marine mammal sera for anti-SPPV antibodies.
Afficher plus [+] Moins [-]Mink SARS-CoV-2 infection in Poland – short communication
2021
Domańska-Blicharz, Katarzyna | Orłowska, Anna | Smreczak, Marcin | Niemczuk, Krzysztof | Iwan, Ewelina | Bomba, Arkadiusz | Lisowska, Anna | Opolska, Justyna | Trębas, Paweł | Potyrało, Patrycja | Kawiak-Sadurska, Magdalena | Rola, Jerzy
Since April 2020, when the first SARS-CoV-2 infection was reported in mink and subsequently in mink farm workers in the Netherlands, it has been confirmed that human-to-mink and mink-to-human transmission can occur. Later, SARS-CoV-2 infections in mink were reported in many European and North American countries. Samples from 590 mink from a total of 28 farms were tested by real-time RT-PCR. Whole genome sequences from one positive farm were generated and genetic relatedness was established. SARS-CoV-2 RNA was detected on a breeder farm with stock of 5,850 mink. Active viraemia was confirmed in individually tested samples with Ct values respectively between 19.4 and 29.6 for E and N gene fragments. Further testing of samples from culled animals revealed 70% positivity in throat swabs and 30% seropositivity in blood samples. Phylogenetic analysis of full-length nucleotide sequences of two SARS-CoV-2 isolates revealed that they belong to the 20B Nextstrain clade. Several nucleotide mutations were found in analysed samples compared to the reference Wuhan HU-1 strain and some of them were nonsynonymous. We report the infection of mink with SARS-CoV-2 on one farm in Poland and the results of subsequent analysis of virus sequences from two isolates. These data can be useful for assessment of the epidemiological situation of SARS-CoV-2 in Poland and how it endangers public health.
Afficher plus [+] Moins [-]Occurrence of Marek’s disease in Poland on the basis of diagnostic examination in 2015–2018
2020
Marek’s disease (MD) is a tumourous disease caused by Marek’s disease virus (MDV) and most commonly described in poultry. The aim of the study was to determine the occurrence of Marek’s disease virus infections in Poland and analyse clinical cases in the years 2015–2018. The birds for diagnostic examination originated from 71 poultry flocks of various types of production. Birds were subjected to anatomopathological examination post mortem, during which liver and spleen sections and other pathologically changed internal organs were taken. These sections were homogenised with generally accepted methods, then total DNA was isolated and amplified with a real-time PCR. A pair of primers complementary to the MDV genome region encoding the meq gene were used. MDV infection was found predominantly in broiler chicken flocks (69.01%), and also in layer breeder (9.85%) and commercial layer flocks (7.04% each). The results of research conducted in the years 2015–2018 clearly indicate that the problem of MDV infections is still current.
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