scholarly journals Porcine rotavirus B as primary causative agent of diarrhea outbreaks in newborn piglets

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Flavia Megumi Miyabe ◽  
Alais Maria Dall Agnol ◽  
Raquel Arruda Leme ◽  
Thalita Evani Silva Oliveira ◽  
Selwyn Arlington Headley ◽  
...  
Keyword(s):  
Causative Agent ◽  
High Frequency ◽  
Geographic Region ◽  
Viral Gastroenteritis ◽  
Wild Type ◽  
Newborn Piglets ◽  
Enteric Diseases ◽  
Porcine Rotavirus ◽  
Acute Viral Gastroenteritis

AbstractRotavirus (RV) is considered a major cause of acute viral gastroenteritis in young animals. RV is classified into nine species, five of which have been identified in pigs. Most studies worldwide have highlighted diarrhoea outbreaks caused by RVA, which is considered the most important RV species. In the present study, we described the detection and characterization of porcine RVB as a primary causative agent of diarrhoea outbreaks in pig herds in Brazil. The study showed a high frequency (64/90; 71.1%) of RVB diagnosis in newborn piglets associated with marked histopathological lesions in the small intestines. Phylogenetic analysis of the VP7 gene of wild-type RVB strains revealed a high diversity of G genotypes circulating in one geographic region of Brazil. Our findings suggest that RVB may be considered an important primary enteric pathogen in piglets and should be included in the routine differential diagnosis of enteric diseases in piglets.

scholarly journals Intrachromosomal Recombination Between Well-Separated, Homologous Sequences in Mammalian Cells

Genetics ◽  
1999 ◽  
Vol 152 (2) ◽  
pp. 685-697
Author(s):  
Mark D Baker ◽  
Leah R Read ◽  
Philip Ng ◽  
Barbara G Beatty
Keyword(s):  
Homologous Recombination ◽  
Sister Chromatid ◽  
High Frequency ◽  
Mammalian Cells ◽  
Single Copy ◽  
Class Iii ◽  
Wild Type ◽  
Sister Chromatids ◽  
Original Donor

Abstract In the present study, we investigated intrachromosomal homologous recombination in a murine hybridoma in which the recipient for recombination, the haploid, endogenous chromosomal immunoglobulin μ-gene bearing a mutation in the constant (Cμ) region, was separated from the integrated single copy wild-type donor Cμ region by ∼1 Mb along the hybridoma chromosome. Homologous recombination between the donor and recipient Cμ region occurred with high frequency, correcting the mutant chromosomal μ-gene in the hybridoma. This enabled recombinant hybridomas to synthesize normal IgM and to be detected as plaque-forming cells (PFC). Characterization of the recombinants revealed that they could be placed into three distinct classes. The generation of the class I recombinants was consistent with a simple unequal sister chromatid exchange (USCE) between the donor and recipient Cμ region, as they contained the three Cμ-bearing fragments expected from this recombination, the original donor Cμ region along with both products of the single reciprocal crossover. However, a simple mechanism of homologous recombination was not sufficient in explaining the more complex Cμ region structures characterizing the class II and class III recombinants. To explain these recombinants, a model is proposed in which unequal pairing between the donor and recipient Cμ regions located on sister chromatids resulted in two crossover events. One crossover resulted in the deletion of sequences from one chromatid forming a DNA circle, which then integrated into the sister chromatid by a second reciprocal crossover.

scholarly journals Characterization of binding of Varicella zoster virus vaccine strains to preparations of mouse brain membrane receptors

2020 ◽  
Vol 97 (2) ◽  
pp. 125-133
Author(s):  
Firaya G. Nagieva ◽  
Elena P. Barkova ◽  
Alexandra D. Stroeva ◽  
Alexandr V. Sidorov ◽  
Vera D. Lotte ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Causative Agent ◽  
Membrane Receptors ◽  
Wild Type ◽  
Brain Membrane ◽  
Cold Adapted ◽  
Fetal Fibroblasts ◽  
Diploid Cells ◽  
Virus Strains

Purpose: characterization of vFiraVax (the causative agent of chickenpox - VZV) and vZelVax (the causative agent of shingles - HZ) vaccine strains by their ability to bind to preparations of brain membrane receptors of SPF BALB/c mice.Materials and Methods. The study was performed on cold-adapted vFiraVax VZV and vZelVax HZ vaccine strains developed by the authors on the basis of the wild-type parental pFira VZV virus (chickenpox causative agent) and the latent parental lpZel HZ virus (shingles causative agent); vOka vaccine strains isolated from vaccines against VZV infection from two manufactures (United Kingdom and USA); the HEL-3 strain of diploid cells from human embryonic lung tissue, the MC 27 strain of diploid cells from human embryonic musculocutaneous tissue, primary and diploid cells from guinea pig fetal fibroblasts. The VZV infectivity was estimated by the limiting dilution method using MC 27 cell cultures or guinea pig fetal fibroblasts. The virus titer was measured by the hemadsorption test performed with suspensions of red blood cells from guinea pig or human type 0 positive blood. Negative staining and electron microscopy were used to study the virus preparation. The immunogenicity of vFiraVax VZV and vZelVax HZ virus strains was compared with the immunogenicity of vOka VZV virus strains from different manufacturers by using a cross-neutralization test with immune sera.Results. The Russian cold-adapted vFiraVax VZV and vZelVax HZ vaccine strains, the latent parental lpZel HZ virus and the vOka VZV vaccine strain (United Kingdom) did not bind to preparations of brain neuroreceptors of SPF BALB/c mice as distinct from the wild-type parental pFira VZV variant and vOka VZV vaccine strains (USA); the absent neurotropism of Russian vFiraVax VZV and vZelVax HZ vaccine strains is not connected with the decreased immunogenicity in relation to foreign counterparts; the electron microscope study of the vFiraVax VZV virus containing liquid concentrate detected VZV nucleocapsids.Conclusion. The differences in the VZV ability to bind to preparations of brain membrane receptors of SPF BALB/c mice can be explained by the differences in the technology of vaccine manufacturing, including attenuation techniques, obtaining of the vaccine strain, specific characteristics of the latent parental lpZel HZ virus. The absence of the binding with brain neuroreceptors of SPF mice has been proved for the Russian vFiraVax VZV and vZelVax HZ vaccine strains which was is not connected with a decrease in their immunogenicity. The method of assessment of the binding ability of VZV vaccine strains can be used as a preliminary characteristic of neurotropism for newly created vaccine strains and for vaccine products.

High-Frequency 94 GHz ENDOR Characterization of the Metal Binding Site in Wild-Type Ras·GDP and Its Oncogenic Mutant G12V in Frozen Solution†

Biochemistry ◽  
2006 ◽  
Vol 45 (1) ◽  
pp. 42-50 ◽  
Author(s):  
M. Bennati ◽  
M. M. Hertel ◽  
J. Fritscher ◽  
T. F. Prisner ◽  
N. Weiden ◽  
...  
Keyword(s):  
Binding Site ◽  
Metal Binding ◽  
High Frequency ◽  
Wild Type ◽  
Metal Binding Site ◽  
Frozen Solution

Functional characterization of the H+/K+ ATPase in wild type and gastrin knock-out mice

2007 ◽  
Vol 45 (05) ◽  
Author(s):  
A Schnur ◽  
P Hegyi ◽  
V Venglovecz ◽  
Z Rakonczay ◽  
I Ignáth ◽  
...  
Keyword(s):  
Functional Characterization ◽  
Wild Type ◽  
Knock Out ◽  
Knock Out Mice

Fungus Spaeropsis Malorum peck. One of the currant stalk drying agents

2020 ◽  
Vol 62 ◽  
pp. 172-178
Author(s):  
S. E. Golovin
Keyword(s):  
Causative Agent ◽  
High Frequency ◽  
Frequency Of Occurrence ◽  
Ribes Nigrum ◽  
Black Currant ◽  
Causative Agents ◽  
Pear Trees ◽  
Red Currant

The article highlights the results of research carried out in 2019-2020 to study the reasons for the drying out of the stems of black currant (Ribes nigrum L.), red currant (Ribes rubrum L.) and golden currant (Ribes aureum L.). As a result of research, the fungus Sphaeropsis malorum Peck. in the first in Russia it was revealed from the drying stems of three types of black currants, red currants and golden currants. This  pathogen inhabited currant stems together with fungi from the genus Cytospora spp., causative agents of stem drying. On red currants, it was established that S. malorum was the main causative agent of branch drying, as indicated by the high frequency of occurrence (75.0-83.3 %) of this fungus on the affected stems, compared with species from the genus Cytospora spp. (16.7-33.3 %) and Phomopsis ribesia (25.0 %). Due to the fact that the cultivation of currants in the immediate vicinity of apple and pear trees leads to infection of plants with the fungus S. malorum, it is necessary to avoid planting currants in the vicinity of fruit-bearing seed gardens.

Characterization of Ni/γ-Al2O3 Catalyst Prepared by Atmospheric High Frequency Cold Plasma Jet for CO2 Reforming of CH4

2010 ◽  
Vol 31 (3) ◽  
pp. 353-359
Author(s):  
Xiaoyan CHAI ◽  
Shuyong SHANG ◽  
Gaihuan LIU ◽  
Xumei TAO ◽  
Xiang LI ◽  
...  
Keyword(s):  
High Frequency ◽  
Cold Plasma ◽  
Plasma Jet
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