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A SARS-CoV-2 host infection model network based on genomic human Transcription Factors (TFs) depletion
No full textIn December 2019 a new beta-coronavirus was isolated and characterized by sequencing samples from pneumonia patients in Wuhan, Hubei Province, China. Coronaviruses are positive-sense RNA viruses widely distributed among different animal species and humans in which they cause respiratory, enteric, liver and neurological symptomatology. Six species of coronavirus have been described (HCoV-229E, HCoV-OC43, HCoV-NL63 and HCoV-HKU1) that cause cold-like symptoms in immunocompetent or immunocompromised subjects and two strains of sometimes fatal zoonotic origin that cause severe acute respiratory syndrome (SARS-CoV and MERS-CoV). The SARS-CoV-2 strain is the emerging seventh member of the coronavirus family, which is actually determining a global emergency. In silico analysis is a promising approach for understanding biological events in complex diseases and due to serious worldwide emergency and serious threat to global health, it is extremely important to use bioinformatics methods able to study an emerging pathogen like SARS-CoV-2. Herein, we report on in silico comparative analysis between complete genome of SARS-CoV, MERS-CoV, HCoV-OC43 and SARS-CoV-2 strains, to identify the occurrence of specific conserved motifs on viral genomic sequences which should be able to bind and therefore induce a subtraction of host's Transcription Factors (TFs) which lead to a depletion, an effect comparable to haploinsufficiency (a genetic dominant condition in which a single copy of wild-type allele at a locus, in heterozygous combination with a variant allele, is insufficient to produce the correct quantity of transcript and, therefore, of protein, for a correct standard phenotypic expression). In this competitive scenario, virus versus host, the proposed in silico protocol identified the TFs same as the distribution of TFBSs (Transcription Factor Binding Sites) on analyzed viral strains, potentially able to influence genes and pathways with biological functions confirming that this approach could brings useful insights regarding SARS-CoV-2. According to our results obtained by this in silico approach it is possible to hypothesize that TF-binding motifs could be of help in the explanation of the complex and heterogeneous clinical presentation in SARS-CoV-2 and subsequently predict possible interactions regarding metabolic pathways, and drug or target relationships
Comparision of the cell growth of amniotic fluid samples in different culture media - how to obtain the best results at the lowest costs
No full text17-alpha-ethinylestradiol and norgestrel in combination induce micronucleus increases and aneuploidy in human lymphocyte and fibroblast cultures
No full textOral contraceptives are highly efficient and easily administered drugs; however, it
must not be forgotten that they are composed of chemical substances which can be
classified as potential carcinogens. Testing of a substance for genotoxicity represents
a reliable approach both to evaluate the genetic hazard and to obtain information on
its possible tumorigenic (cancerogenic) properties. The present study was undertaken
to evaluate through carefully planned and controlled investigations the in vitro cytogenetic
effects of oral contraceptives (ethynilestradiol and norgestrel mixed in the
proportion 1:5) using three different concentrations, with two different durations of
treatment (48 and 72 h), on two types of human cells (lymphocytes and fibroblasts)
and a series of short-term test procedures: sister chromatid exchange (SCE), micronucleus
test (MN), and chromosome aberrations (CA). In addition, the FISH procedure
and in vitro anaphase and metaphase preparation analyses were performed. In
contrast to CA and SCE frequencies, the frequency of MN in treated blood lymphocytes
showed higher values by comparison with the controls, although the difference
was statistically significant only for the lowest concentration (P = 0.016). When using
pancentromeric alphoid probes, the FISH procedure gave positive signals in more
than 85% of micronuclei, clearly indicating that MN may contain whole chromosomes
rather than acentric fragments. Unlike the lymphocytes, the fibroblasts showed
dose-dependent effects, although those treated with the highest hormone concentrations
showed an increased number of highly damaged cells (cytoplasmatic vacuolization,
nuclear fragmentation, etc.), a decreased number of anaphase cells, a large number
of which were abnormal, and a reduction of mitotic index. In conclusion, our data
confirm that hormones do not induce structural chromosome aberrations in lymphocytes
and indicate that ethynilestradiol and norgestrel have an aneugenic effect on fibroblast and lymphocyte cultures; FISH analysis on micronuclei from lymphocyte
cultures and anaphase preparations from fibroblast cultures support this hypothesis
Trisomy 13 mosaicism in a phenotypically normal child: description of cytogenetic and clinical findings from early pregnancy beyond 2 years of age
No full textSister chromatid exchange (SCE) and micronucleus (MN) frequencies in lymphocytes of gasoline station attendants
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SCE frequency measurement could be useful in the prenatal diagnosis of Roberts syndrome
No full textIn a previously published article (Resta et al., 2006) on Robert's syndrome in prenatal diagnosis, a case of a 36-year-old woman and her 36-year-old, nonconsanguineous husband were presented. Our findings suggest the existence of nonsense mediated decay (NMD) variability which could account for the varying severity reported in carriers of identical mutations. Furthermore, fetal cells were used to evaluate the influence of premature centromere separation (PCS) on the sister chromatid exchange (SCE) and micronucleus (MN) frequency. Given the similar variation observed in the SCE frequencies, dependent on tissue/cell type (amniotic fluid sample, chorionic villus sampling) and duration of in vitro cultures (48 hours or 72 hours), the idea was that this new piece of information could be interesting. It seems that the SCE frequency increased proportionally to the cell cycle increasing (1 degrees < 2 degrees < 3 degrees ... n). Obviously, our observations are too scarce to draw conclusions, but further investigation could be useful to corroborate or dispute these results, considering that the two techniques, (MN and SCE), are simple to perform and do not require expensive laboratory equipment
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