Blood leucocytes, sediments of uterine flush fluid (UFF), eggs and embryos from 25 BLV-positive donor cows were tested for bovine leukemia (BLV) and bovine syncytial (BSV) viruses by cocultivation with fetal lamb spleen cells and by applying syncytium induction and immunofluorescence tests. BLV was diagnosed in 11/15 (73.3%) leucocyte and 4/25 (16.0%) UFF-sediment specimens as compared to BSV in 14/15 (93.3%) and 21/25 (84.0%) of the similar specimens and neither BLV or BSV were found in 26 eggs and 60 embryos collected from 20 of the 25 cows. Detection of BLV antigens by immunofluorescence was hampered by the competitive replication of both BLV and BSV and competitive growth in indicator cells and uterine cells. As BLV has not been observed in cells of UFF sediments, it was probably isolated from leucocytes present in the lumen of uterus or from blood seeping out from inapparent vessel damage during flushing. Isolation of BLV in UFF sediments gives additional evidence to the concept of a transplacental transmission by a not yet elucidated mechanism. The high rate of BSV recovery from cells of UFF sediments indicated that this virus is more wide-spread than previously shown and that it may play a role in causing disorders of the reproductive tract.
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Sci Total Environ
January 2025
Universidade Federal do Pará, Programa de Pós-Graduação em Geologia e Geoquímica, Rua Augusto Corrêa, 1, Campus Guamá, PA 66075-110 Belém, Pará, Brazil.
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December 2024
Programa de Pós-Graduação em Ciências Ambientais e Conservação, Instituto de Biodiversidade e Sustentabilidade, Universidade Federal do Rio de Janeiro, Macaé, RJ, Brazil. Electronic address:
Land use and land cover changes (LULCC) are a global environmental issue that has impacted biogeochemical cycles worldwide. Sedimentary records can demonstrate the effects of LULCC on aquatic ecosystems, where the recent urbanization has been linked to changes in carbon and nitrogen burial. In this study, we reconstructed long-term LULCC and sedimentary records of carbon (C), nitrogen (N), phosphorus (P), and sediment burial rates in a eutrophic tropical coastal lagoon affected by recent urban expansion.
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October 2024
Department of Pure and Applied Sciences, Università Degli Studi di Urbino "Carlo Bo", 61029, Urbino, Italy. Electronic address:
Ecotoxicology
August 2024
Centre for Mineral Technology, CETEM/MCTI, Av. Pedro Calmon, 900. Cidade Universitária, Rio de Janeiro, RJ, Brazil.
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View Article and Find Full Text PDFEnviron Sci Pollut Res Int
May 2024
Faculdade de Geologia (FGEL), Universidade Do Estado Do Rio de Janeiro (UERJ), Rio de Janeiro, RJ, Brazil.
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