21 research outputs found
Characterization of novel Bovine Leukemia Virus (BLV) antisense transcripts by deep sequencing reveals constitutive expression in tumors and transcriptional interaction with viral microRNAs
Pneumovirus infection and effects on dendritic cells of mice
Respiratory syncytial virus (RSV) is the primary viral pathogen responsible for lower respiratory tract disease in neonates and young children worldwide. By the age of two, virtually all children have been infected with RSV, and approximately 40% of them develop lower respiratory tract infections. In addition to acute morbidity, an association between RSV infection in early childhood and later development of recurrent wheezing and airway hyperresponsiveness (AHR) has been repeatedly demonstrated.In this work we established a method for propagating pneumonia virus of mice (PVM) in a baby hamster kidney-21 (BHK-21) cell line. We also modified the standard plaque assay method and established a reliable and, most importantly, reproducible way to quantitate PVM. In our work we used PVM strain 15 to successfully establish an in vivo animal model for RSV disease in Balb/c and C57/Bl mice. Different susceptibility/resistance patterns to a pathogen exist for different mouse strains. In the case of Balb/c and C57/Bl mice, these patterns are well characterized for several pathogens including Leishmania major and adenovirus type 1. Our comparative study demonstrated clear differences in susceptibility to PVM strain 15 infection between Balb/c and C57/Bl mice; Balb/c mice being more susceptible. In peripheral sites, dendritic cells (DCs) serve as sentinel cells that take up and process antigens. Numerous studies revealed that certain pathogens stimulate changes in DC phenotypic characteristics and thus contribute to functional alterations that lead to inappropriate T cell activation and disease augmentation. To examine effects of PVM on DCs, we infected bone marrow dendritic cells (BM-DCs) derived from both mouse strains with PVM, and evaluated their phenotypic and functional characteristics 24 hours post infection. Under these experimental conditions, PVM infected BM-DCs did not show a significant increase in the expression of costimulatory and major histocompatibility complex class II (MHC II) molecules compared to uninfected controls. Furthermore, there were no changes in the ability of PVM-infected DCs to take up soluble antigen. The production of IL-12p70, the pivotal cytokine in the development of a Th1-type response, by the PVM-infected BM-DCs was not significantly different from uninfected cells. In addition, there was no significant impact of PVM infection on the ability of DCs to induce naïve T cell proliferation
ANALYSIS OF PRODUCING MILK AND DEVELOP PERSPECTIVE OF IN THE REPUBLIC OF SERBIA
Research in this paper work tends to show basic characteristic in producing
cow and sheep milk in the Republic of Serbia in period 1998 – 2007. Paper work
analyzed production cow and sheep milk in regions in Central Serbia and
Vojvodina, also paper analyzed changes which held in production during
researching period and participation of production cow and sheep milk in the
Republic of Serbia, using base index.
Paper work try to give theoretical and practical contribution for farmers who
are involving directly or indirectly in milk production, to have aims in using
adequate measure to develop their cattle-breeding and sheep farming, particularly
in milk area
ORGANIC FARMING PRODUCTION AND ROLE OF MARKETING
For the reason of constant need for rising food production which are determinate
with a large number of famine all over the world, it was intensively developed
technique and technology in agricultural production which based on unnatural
synthetic materials, where belong mineral fertilizers, pesticides, factors which
stimulate rise, hormones, etc., also which contributed that outputs have large rise.
However, uncontrolled process of using agrochemical substances, process of
intensive using hard agricultural mechanization, and also process of pollution,
resulted that we have problems with environment. Organic farming has developed
from that reason as a result on ecological degradation and jeopardizing human
population.
This paper work tries to show importance of organic farming production, but also
look towards importance of marketing in organic farming production of food and
way how to sell it on the market
CHEESES WITH ADDITIONS
In this paper work we show data about cheese production in world and in
Serbia, different cheese sorts and different cheese addition in contexts of achieving
specific season, nutritive and functional characteristics, especially from the aspects
of official Statutes about quality and other requirement for milk, milk products,
composite milk products and starter culture
INVESTMENT ECONOMY IN IRRIGATION SYSTEM IN CLIMATIC CONDITIONS IN RASPBERRY REGION OF ARILJE AREA
Тhis work have analysed climatic water balance in Raspberry region of
Arilje in vegetative cycle of raspberry, in function of yield fluctuation in natural
condition and irrigation water balance regime of soil and economical payable for
introduction of irrigation in raspberry production.
Introduction of irrigation, raspberry yields can be increased in average 1,8-
3,3 times in relation to yield without irrigation, and investment in mini-irrigation
system construction, on surface for just one plant, with water supporting from local
watercourse can be pay off for one growing season. Raspberry reacts on irrigation
with increasing yield in such a level that it is profitable to invest in mini-irrigation
system construction every year again
Cis-perturbation of cancer drivers by the HTLV-1/BLV proviruses is an early determinant of leukemogenesis
Human T-cell leukaemia virus type-1 (HTLV-1) and bovine leukaemia virus (BLV) infect T- and B-lymphocytes, respectively, provoking a polyclonal expansion that will evolve into an aggressive monoclonal leukaemia in ∼5% of individuals following a protracted latency period. It is generally assumed that early oncogenic changes are largely dependent on virus-encoded products, especially TAX and HBZ, while progression to acute leukaemia/lymphoma involves somatic mutations, yet that both are independent of proviral integration site that has been found to be very variable between tumours. Here, we show that HTLV-1/BLV proviruses are integrated near cancer drivers which they affect either by provirus-dependent transcription termination or as a result of viral antisense RNA-dependent cis-perturbation. The same pattern is observed at polyclonal non-malignant stages, indicating that provirus-dependent host gene perturbation contributes to the initial selection of the multiple clones characterizing the asymptomatic stage, requiring additional alterations in the clone that will evolve into full-blown leukaemia/lymphoma.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
The Landscape And Evolution Of Somatic Mutations In Bovine Leukemia Virus Induced Tumors
Bovine Leukemia Virus (BLV) is a deltaretrovirus that integrates into B-cells producing a lifelong infection in cattle. Like its close relative Human T-cell leukemia virus-1 (HTLV-1), BLV induces an aggressive leukemia/lymphoma in about ~5% of infected individuals. While not a natural host it is possible to infect sheep with BLV and in contrast to cattle, all infected sheep develop tumors at an accelerated rate (~18 months). Historically research into both viruses has primarily focused on their transcripts/proteins. However secondary somatic events are likely to be important as only a subset of infected individuals, following many decades of infection, develop a tumor. At the current time little is known about the landscape of somatic changes in BLV induced tumors and the timing of their occurrence. To address this we have carried out whole genome sequencing of BLV induced tumors from two cattle, and from five sheep with matched normal tissue. This revealed frequent aneuploidy, with orthologous regions of the genome involved in both species and elevated mitochondria DNA copy numbers in tumors. Recurrent structural variants (SVs) were seen affecting the tumor suppressors CDKN2A and ARID1A, both on OAR2. On average ~1400 somatic SNVs were observed in each ovine tumor, with high/moderate impact variants in known cancer drivers genes such as KMT2A, ATRX, RPL22 and KRAS. The five sheep were also sampled at regular time points, prior to leukemia onset, allowing us to examine tumor clone evolution. High throughput sequencing of proviral integration sites showed that the tumor clone represents only a small fraction of the infected cells for the majority of the disease, only expanding rapidly in the terminal stages. Low coverage sequencing of samples prior to tumor development indicates that aneuploidy of OAR9 is a feature of the majority of BLV infected clones. Preliminary nested PCR also showed that many SVs were present prior to tumor development. High throughput approaches are being developed to track both SVs and SNV in the preleukemic stages of the disease
Identification and characterization of novel bovine leukemia virus (BLV) antisense transcripts in leukemic and pre-leukemic clones
The deltaretrovirus Bovine Leukemia Virus (BLV) is closely related to the Human T-cell leukemia virus-1 (HTLV-1). Cattle are the natural host of BLV where it integrates into B-cells, produces a lifelong infection. Most infected animals remain asymptomatic but following a protracted latency period about ~5% develop an aggressive leukemia/lymphoma, mirroring the disease trajectory of HTLV-1. Like the case in HTLV-1 the 5’LTR BLV provirus is transcriptionally silent in tumors, however the provirus is not entirely quiescent, constitutively express the BLV microRNAs in tumors. Using RNA-seq, we found that in addition to microRNAs, the BLV provirus also constitutively expresses two antisense transcripts in all BLV infected samples examined. The first transcript (AS1) has alternate potential polyadenylation sites generating a short transcript of ~600bp (AS1-S) and a less abundant longer transcript of ~2200bp (AS1-L). Alternative splicing also creates a second transcript of ~400bp (AS2) utilizing the first exon of AS1. Production of AS transcripts from the 3’LTR was supported by reporter assays demonstrating that the BLV LTR has substantial and Tax-independent antisense promoter activity. BLV AS transcripts predominantly localize in the nucleus. Examination of protein coding potential showed AS2 to be non-coding, while the AS1-S/L transcripts coding potential is ambiguous, with a small potential open reading frame (ORF) of 264bp present. The AS1-L transcript overlaps the BLV microRNAs transcribed in the sense direction. Using high throughput sequencing of RNA-ligase-mediated (RLM) 5' RACE products, we show that the perfect complementary between the transcripts leads to RNA-induced silencing complex (RISC) mediated cleavage of AS1-L. Furthermore, experiments using BLV proviruses where the microRNAs were removed or inverted point to additional transcriptional interactions between the two viral RNA species. Knock down of AS1-S/L using locked nucleic acids (LNAs) showed no obvious effect on the cells phenotype. While a detailed elucidation of the BLV antisense transcripts function remains in the future, the constitutive expression in all samples examined, points to a vital role for the transcripts in the life cycle and oncogenic potential of BLV
Somatic Structural And Numerical Aberrations In Bovine Leukemia Virus Induced Tumors
Bovine Leukemia Virus (BLV) is a deltaretrovirus that integrates into B-cells producing a lifelong infection in cattle. Like its close relative Human T-cell leukemia virus-1 (HTLV-1), BLV induces an aggressive leukemia/lymphoma in about ~5% of infected individuals. While not a natural host it is possible to infect sheep with BLV and in contrast to cattle, all infected sheep develop tumors at an accelerated rate (~18 months). Historically research into both viruses has primarily focused on their transcripts/proteins. However secondary events are likely to be important as only a subset of infected individuals, following many decades of infection, develop a tumor. At the current time little is known about the landscape of somatic changes in BLV induced tumors. To examine gross numerical and structural variants (SVs) we assayed 12 bovine tumors on the BovineSNP50 Illumina BeadChip as well as 22 ovine tumors on the OvineSNP50 Illumina BeadChip. We also carried out whole genome sequencing (~30X) on 4 ovine tumors with matched normal tissue. Initial examination of the tumors revealed frequent aneuploidy, with orthologous regions of the genome involved in both species. Focal SVs identified included an amplification (>4 copies) of the terminus of BTA16 in three tumors (contains PTPRC & miR-181), while the tumor suppressor CDKN2A on OAR2 was deleted in multiple ovine tumors. For the 4 sequenced tumors multiple time points over the course of infection were available allowing us to determine when these SVs arose via nested PCR. Interestingly we observed that the SVs involving well know cancer driver genes generally appear many months prior to tumor development. These preliminary results indicate that tumors induced by HTLV-1 and BLV display somatic structural changes that impinge on overlapping sets of genes and point to the emergence of SVs affecting cancer driver genes in the preleukemic clone, well before the clone undergoes rapid expansion