200 research outputs found
MISEXPRESSION OF CANCER/TESTIS (CT) GENES IN TUMOR CELLS AND THE POTENTIAL ROLE OF DREAM COMPLEX AND THE RETINOBLASTOMA PROTEIN RB IN SOMA-TO-GERMLINE TRANSFORMATION
Misexpression of germline genes like Cancer Testis (CT) genes, called a soma-to-germline transformation, is a phenomenon linked to tumorigenesis. However, the mechanisms underlying this phenomenon are poorly understood. A soma-to-germline transformation in Caenorhabditis elegans occurs due to the loss function of the highly conserved DREAM (Dp, Retinoblastoma (Rb)-like, E2F, and MuvB) transcriptional repressor complex. In mammalian cells, the DREAM complex (Muvb core complex, E2F4/5, DP1/2, and p130/p107 proteins), as well as the Retinoblastoma protein (pRb), are implicated in transcriptional repression of cell cycle genes in quiescence or G0. We hypothesize that the expression of CT genes in malignant cells occurs because of the loss of activities of DREAM complex or pRb, similar to how the soma-to-germline transformation occurs in C. elegans. Thus, we expect that cancer cells that express CT genes will either fail to arrest in G0 or display defective repression of key cell cycle genes. To test sensitivity cells to arrest in response to limiting growth conditions, we did flow cytometry to measure the DNA content of 10 cell lines. We found that seven cell lines arrested in G0/G1, indicating that these cells have downregulated CT genes expression, and DREAM or Rb is involved in repressing cell cycle in G0/G1. This result also suggested that in the cells that did not arrest, both DREAM and Rb are inactive. Next, to test the mRNA expression of CT genes of all the cell lines, we did mRNA analysis of CT genes. We found that CT genes are expressed in proliferating cells of both cells that can arrest under limiting growth conditions and the cells that do not, indicating we did not observe a difference in mRNA expression between cells that arrest and cells that do not. To test if CT misexpression is associated with dysfunction in either Rb or DREAM, we did further analyses to test early and late cell cycle genes expression in SW480, NCI-H1299, and 8MGBA, comparing the expression of cell cycle cells in proliferating cells to arrested cells in G0/G1. We found that mRNA expression of early cell cycle genes MCM5, ORC1, and CDC45 are downregulated, as expected since DREAM and Rb regulation of these genes overlap. However, DREAM solely regulates G2/M genes like CCNB2, PBK, and BUB1. We found that G2/M genes were not in significantly downregulated in NCI-H1299 and SW-480 cells, suggesting that DREAM is dysfunctional in these cell lines. As a secondary test of DREAM and Rb function, we performed luciferase reporter assays with promoters of DREAM and Rb target genes in SW480 and NCI-H1299 cell lines. Surprisingly, we observed that Rb is dysfunctional in SW480 cells. Together, these studies will facilitate future studies into the link between cell cycle regulation and CT upregulation in cancer cells
Retrieval performance of select search engines in the field of physical sciences
The study aims to provide a systematic evaluation of the search engines on the basis of two information retrieval parameters (precision and relative recall) with reference to physical sciences. It employed ‘Web of Science’ to identify data (one to three word queries) of highly ranked authors who have contributed to the discipline of physical sciences. The three English language search engines (Google, Yahoo and Bing) were selected on the basis of ranking of ‘Alexa’ (Actionable Analytics for the Web). The study reveals that in all (one, two and three word) queries ‘Google’ obtained highest precision and relative recall followed by ‘Yahoo’ and ‘Bing’. It further shows that ‘Google’ and ‘Yahoo’ achieve the highest ‘precision’ and ‘relative recall’ due to their wide coverage. Bing once prominent one, however lags behind in retrieval effectiveness
AMELIORATIVE ROLE OF SILYMARIN AGAINST ASPARTAME–INDUCED BIOCHEMICAL CHANGES, OXIDATIVE STRESS, INFLAMMATORY EFFECT AND GENOTOXICITY IN MALE ALBINO RATS
Objective: Aspartame (ASP) is one of the most common artificial sweeteners. It has been recorded to be safe by World Health Organization. However, numerous publications have concluded that ASP is a genotoxic and carcinogenic sweetener.
Methods: The current study aims to examine the effect of ASP consumption (250 mg/kg body weight/day for 90 d) on some biochemical parameters, oxidative/antioxidative status in different tissues, Tumor Necrosis Factor-α (TNF-α), chromosomal aberration (CA) frequency and mitotic index (MI) percentage in addition to the possible ameliorative role of silymarin (50 mg/kg body weight/day for 90 d) against ASP-induced toxicity in male albino rats.
Results: The present results have confirmed that ASP is able to induce significant increase in the blood glucose level, liver, kidney and lipid function tests, Malondialdehyde (MDA) level, serum TNF-α level, frequency of CA and MI%. Meanwhile, Glutathione reduced level (GSH), Glutathione–S-transferase (GST) and catalase activity (CAT) were decreased by ASPadministration. Recovery group showed slight enhancement in all parameters but remained significant as compared to the control group. Co-administration of ASP with silymarin showed greater improvement than the recovery group.
Conclusion: Silymarin have an ameliorative role against biochemical oxidative stress, inflammatory changes in blood and different tissues, chromosomal aberrations and MI% induced by ASP administration
NÃveis De Estrona E Estradiol Em Pacientes Com Câncer De Mama Usando Anastrozol Não Estão Relacionados Ao Ãndice De Massa Corpórea
Obesity is associated with an increased risk for breast cancer. Recent studies have shown that aromatase inhibitors may be less effective in women with a high body mass index (BMI). The aim of this study was to establish the relationship between the BMI and plasma estrone and estradiol levels in postmenopausal women with hormone receptor-positive breast cancer using anastrozole. Methods In this cohort study, the patients were divided into three groups according to BMI (normal weight, overweight and obese) to compare and correlate plasma hormone levels before starting anastrozole hormone therapy and three months after treatment. Plasma hormone levels were compared for age and use of chemotherapy. Results A statistically significant reduction in estrone and estradiol levels was observed between baseline and three months after starting the anastrozole treatment (p 0.05), but a significant reduction in plasma estrone levels was observed after three-months' treatment relative to baseline in all groups, as well as a reduction in estradiol in the obese group (p 65 years had no influence on plasma steroid levels. Conclusion Changes in estrone and estradiol levels in the studied groups were not associated with BMI, chemotherapy or age. Copyright © 2016, Federacao Brasileira das Sociedades de Ginecologia e Obstetricia. All rights reserved
Filter-Based Product Search Engines With Dynamic Component Ranking
The use of faceted browsing is common on shopping and comparison websites. When dealing with problems of this kind, it is usual practise to apply a specified set of features in a certain order. This tactic suffers from two major flaws that undermine its effectiveness. First things first: before you do anything else, you need to make sure that you set aside a significant amount of time to compile an effective list. Second, if you have a certain number of aspects and all of the products that are relevant to your search are tagged with the same aspect, then that particular aspect is basically worthless. This article presents a method for doing online business that makes use of a dynamic facet ordering system. On the basis of measurements for specificity and dispersion of aspect value dispersion, the entirely automated system assigns ratings to the characteristics and facets that lead to a speedy drill-down for each and every prospective target product. In contrast to the methodologies that are currently in use, the framework takes into consideration the subtleties that are specific to e-commerce. These nuances include the need for several clicks, the grouping of facets according to the traits that they share, and the predominance of numerical facets. In a large-scale simulation and user survey, our approach performed much better than the baseline greedy strategy, the facet list prepared by domain experts, and the state-of-the-art entropy-based solution. These comparisons were made using the same data
A new bow-shock source with bipolar morphology in the vicinity of Sgr A*
Here we present a new bowshock blue-shifted source in the close vicinity of
Sgr A* that we name X8. We use data-sets that are based on SINFONI observations
with the Very Large Telescope. We can trace the source between 2006 and 2016 in
the blue-shifted line maps and it shows not only positional similarities to X7
but also the same spectral footprint. The symmetry axis of both extended
sources points towards Sgr A* and exhibits [Fe III] emission lines that arise
due to wind-wind shocks. In particular, the source X8 has a bipolar morphology,
which makes it the closest bipolar source in the vicinity of Sgr A*. In
addition, we can trace a K-band continuum counterpart of X8. This points
towards a stellar counterpart to the line-map emission. Overall, the source X8
can be interpreted as either a Young Stellar Object or a young planetary
nebula, which makes this source unique among so-far detected main-sequence OB
stars in this region.Comment: Accepted for publication by A&A, 15 pages, 13 figure
The protective performance of selected UK police body armor challenged by M75 grenades
UK Police ‘soft’ body armor is designed to provide protection from sharp-weapons and low-velocity pistol ammunition; if ‘hard’ armor plates are fitted then high-velocity rifle protection is provided. Several different levels of protection for both soft and hard armor are available and these are tailored to the individual police officers’ role. The level of protection offered by these types of armor from fragmentation threats is not known as fragmentation is not typically considered a threat to UK Police Officers. However, fragmentation from devices such as grenades may be a threat to certain specialized units and during terrorist incidents. In this work, neither the soft nor hard UK Police body armor (HG2 and RF1 respectively) investigated were perforated when challenged by M75 Yugoslavian grenades at a distance of 1 m from the point of detonation. The effect due to blast was not considered. The work has provided confidence regarding the performance of selected police body armor against fragmentation from a selected grenade threat
Host galaxies of merging compact objects: mass, star formation rate, metallicity, and colours
Characterizing the properties of the host galaxies of merging compact objects provides essential clues to interpret current and future gravitational-wave detections. Here, we investigate the stellar mass, star formation rate (SFR), metallicity, and colours of the host galaxies of merging compact objects in the local Universe by combining the results of MOBSE population-synthesis models together with galaxy catalogues from the EAGLE simulation. We predict that the stellar mass of the host galaxy is an excellent tracer of the merger rate per galaxy n(GW) of double neutron stars (DNSs), double black holes (DBHs), and
black hole-neutron star binaries (BHNSs). We find a significant correlation also between n(GW) and SFR. As a consequence, n(GW) correlates also with the r-band luminosity and with the g-r colour of the host galaxies. Interestingly, greater than or similar to 60 per
cent, greater than or similar to 64 per cent, and greater than or similar to 73 per cent of all the DNSs, BHNSs, and DBHs merging in the local Universe lie in early-type galaxies, such as NGC 4993. We predict a local DNS merger rate density of similar to 238 Gpc(-3) yr(-1) and a
DNS merger rate similar to 16-121 Myr(-1) for Milky Way-like galaxies. Thus, our results are consistent with both the DNS merger rate inferred from GW170817 and the one inferred from Galactic DNSs
Nuclear Activity and the Conditions of Star-formation at the Galactic Center
The Galactic Center is the closest galactic nucleus that can be studied with
unprecedented angular resolution and sensitivity. We summarize recent basic
observational results on Sagittarius A* and the conditions for star formation
in the central stellar cluster. We cover results from the radio, infrared, and
X-ray domain and include results from simulation as well. From (sub-)mm and
near-infrared variability and near-infrared polarization data we find that the
SgrA* system (supermassive black hole spin, a potential temporary accretion
disk and/or outflow) is well ordered in its geometrical orientation and in its
emission process that we assume to reflect the accretion process onto the
supermassive black hole (SMBH).Comment: 11 pages, 4 figures, 1 table; published in PoS-SISSA Proceedings of
the: Frontier Research in Astrophysics - II, 23-28 May 2016, Mondello
(Palermo), Ital
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