863 research outputs found
Adverse prognostic and predictive significance of low DNA-dependent protein kinase catalytic subunit (DNA-PKcs) expression in early-stage breast cancers
Background: DNA-dependent protein kinase catalytic subunit (DNA-PKcs), a serine threonine kinase belonging to the PIKK family (phosphoinositide 3-kinase-like-family of protein kinase), is a critical component of the non-homologous end joining (NHEJ) pathway required for the repair of DNA double strand breaks. DNA-PKcs may be involved in breast cancer pathogenesis. Methods: We evaluated clinicopathological significance of DNA-PKcs protein expression in 1161 tumours and DNA-PKcs mRNA expression in 1950 tumours. We correlated DNA-PKcs to other markers of aggressive phenotypes, DNA repair, apoptosis and cell cycle regulation. Results: Low DNA-PKcs protein expression was associated with higher tumour grade, higher mitotic index, tumour de-differentiation and tumour type (ps<0.05). Absence of BRCA1, low XRCC1/SMUG1/APE1/Polβ were also more likely in low DNA-PKcs expressing tumours (ps<0.05). Low DNA-PKcs protein expression was significantly associated with worse breast cancer specific survival (BCCS) in univariate and multivariate analysis (ps<0.01). At the mRNA level, low DNA-PKcs was associated with PAM50.Her2 and PAM50.LumA molecular phenotypes (ps<0.01) and poor BCSS. In patients with ER positive tumours who received endocrine therapy, low DNA-PKcs (protein and mRNA) was associated with poor survival. In ER negative patients, low DNA-PKcs mRNA remains significantly associated with adverse outcome. Conclusions: Our study suggests that low DNA-PKcs expression may have prognostic and predictive significance in breast cancers
A Vision for Ice Giant Exploration
From Voyager to a Vision for 2050: NASA and ESA have just completed a study of candidate missionsto Uranus and Neptune, the so-called ice giant planets. It is a Pre-Decadal Survey Study, meant to inform the next Planetary Science Decadal Survey about opportunities for missions launching in the 2020's and early 2030's. There have been no space flight missions to the ice giants since the Voyager 2 flybys of Uranus in 1986 and Neptune in 1989. This paper presents some conclusions of that study (hereafter referred to as The Study), and how the results feed into a vision for where planetary science can be in 2050. Reaching that vision will require investments in technology andground-based science in the 2020's, flight during the 2030's along with continued technological development of both ground- and space-based capabilities, and data analysis and additional flights in the 2040's. We first discuss why exploring the ice giants is important. We then summarize the science objectives identified by The Study, and our vision of the science goals for 2050. We then review some of the technologies needed to make this vision a reality
Population-Level Effects of Human Papillomavirus Vaccination Programs on Infections with Nonvaccine Genotypes
We analyzed human papillomavirus (HPV) prevalences during prevaccination and postvaccination periods to consider possible changes in nonvaccine HPV genotypes after introduction of vaccines that confer protection against 2 high-risk types, HPV16 and HPV18. Our meta-analysis included 9 studies with data for 13,886 girls and women ≤19 years of age and 23,340 women 20–24 years of age. We found evidence of cross-protection for HPV31 among the younger age group after vaccine introduction but little evidence for reductions of HPV33 and HPV45. For the group this same age group, we also found slight increases in 2 nonvaccine high-risk HPV types (HPV39 and HPV52) and in 2 possible high-risk types (HPV53 and HPV73). However, results between age groups and vaccines used were inconsistent, and the increases had possible alternative explanations; consequently, these data provided no clear evidence for type replacement. Continued monitoring of these HPV genotypes is important
Survey sequencing and radiation hybrid mapping to construct comparative maps.
In MURPHY WJ (ed.) Phylogenomics, Humana Press. (Methods in Molecular Biology, 422)International audienceRadiation hybrid (RH) mapping has become one of the most well-established techniques for economically and efficiently navigating genomes of interest. The success of the technique relies on random chromosome breakage of a target genome, which is then captured by recipient cells missing a preselected marker. Selection for hybrid cells that have DNA fragments bearing the marker of choice, plus a random set of DNA fragments from the initial irradiation, generates a set of cell lines that recapitulates the genome of the target organism several-fold. Markers or genes of interest are analyzed by PCR using DNA isolated from each cell line. Statistical tools are applied to determine both the linear order of markers on each chromosome, and the confidence of each placement. The resolution of the resulting map relies on many factors, most notably the degree of breakage from the initial radiation as well as the number of hybrid clones and mean retention value.A high-resolution RH map of a genome derived from low pass or survey sequencing (coverage from 1 to 2 times) can provide essentially the same comparative data on gene order that is derived from high-coverage (greater than x7) genome sequencing. When combined with fluorescence in situ hybridization, RH maps are complete and ordered blueprints for each chromosome. They give information about the relative order and spacing of genes and markers, and allow investigators to move between target and reference genomes, such as those of mouse or human, with ease although the approach is not limited to mammal genomes
Candidate cryovolcanic regions on Ganymede: a target priority for JUICE
Jupiter’s largest moon, Ganymede, is the main target of the upcoming ESA mission JUpiter ICy moons Explorer (JUICE), which is planned to launch in 2023. One of the top priorities of the JUICE mission is investigation of past and/or recent cryovolcanic and tectonic activity and the exchange processes with the subsurface and possibly with the ocean (Grasset et al., 2013). Following that objective, the science team has defined ‘potential cryovolcanic regions’ as a category of high interest for observation by JUICE (Stephan et al. 2021). Hence, for preparation of the scientific return of the mission, it is important to study in detail the regions that are considered to be good candidates for past or present activity
Promotion of a healthy lifestyle among 5-year-old overweight children: Health behavior outcomes of the 'Be active, eat right' study
Background: This study evaluates the effects of an intervention performed by youth health care professionals on child health behaviors. The intervention consisted of offering healthy lifestyle counseling to parents of overweight (not obese) 5-year-old children. Effects of the intervention on the child having breakfast, drinking sweet beverages, watching television and playing outside were evaluated. Methods. Data were collected with the 'Be active, eat right' study, a cluster randomized controlled trial among nine youth health care centers in the Netherlands. Parents of overweight children received lifestyle counseling according to the intervention protocol in the intervention condition (n = 349) and usual care in the control condition (n = 288). Parents completed questionnaires regarding demographic characteristics, health behaviors and the home environment at baseline and at 2-year follow-up. Cluster adjusted regression models were applied; interaction terms were explored. Results: The population for analysis consisted of 38.1% boys; mean age 5.8 [sd 0.4] years; mean BMI SDS 1.9 [sd 0.4]. There were no significant differences in the number of minutes of outside play or television viewing a day between children in the intervention and the control condition. Also, the odds ratio for having breakfast daily or drinking two or less glasses of sweet beverages a day showed no significant differences between the two conditions. Additional analyses showed that the odds ratio for drinking less than two glasses of sweet beverages at follow-up compared with baseline was significantly higher for children in both the intervention (p < 0.001) and the control condition (p = 0.029). Conclusions: Comparison of the children in the two conditions showed that the intervention does not contribute to a change in health behaviors. Further studies are needed to investigate opportunities to adjust the intervention protocol, such as integration of elements in the regular well-child visit. The intervention protocol for youth health care may become part of a broader approach to tackle childhood overweight and obesity. Trial registration. Current Controlled Trials ISRCTN04965410
Ganymede paterae: a priority target for JUICE
The JUpiter ICy moons Explorer (JUICE), the first large-class of the European Space Agency (ESA), is planned to launch in 2023, and one of its main goals is to make detailed observations of Jupiter’s moon Ganymede. The mission will investigate the past and/or recent cryovolcanic and tectonic activity of the moon and the exchange processes with the subsurface and possibly with the ocean. Recently, the science team defined “potential cryovolcanic regions” as a category of high interest for observation by JUICE (Stephan et al., 2021). For preparation of the scientific return of the mission, it is important to study in detail the regions that are considered to be good candidates for past/present activity. Light material areas on Ganymede imaged by Voyager have been suggested to represent dark terrain resurfaced by cryovolcanic flows (e.g., Parmentier et al., 1982), while the dark terrain’s speculated cryovolcanic origin was later disputed based on higher-resolution images of the Galileo mission. Additional Galileo data showed the significant role of tectonism in the formation of the light material areas, while the role of cryovolcanism remained inconclusive. Currently, small, isolated depressions called ‘paterae’, are the best candidate regions for cryovolcanic activity on Ganymede and suggested to be potential caldera-like cryovolcanic source vents (e.g., Spaun et al., 2001). Their nature has been interpreted as “possible cryovolcanic source vents for extrusion of clean icy material to form light material units” (Collins et al., 2013), and their small size is consistent with a cryovolcanic origin that operates on a local scale. The high-resolution JUICE camera, JANUS, in combination with other remote sensing instruments, is expected to resolve many of the mysteries concerning cryovolcanism on Ganymede and the origin of the moon’s varied geologic features. The “potential cryovolcanic regions” identified by the JUICE team includes 19 out of 30 paterae mapped by Collins et al., (2013) using Voyager and Galileo images. In this study, with the aim to enhance the preparation of the JUICE mission and its science return, we present: a thorough view of all 19 paterae regions; a detailed geomorphological characterization and comparison between the Ganymede paterae with paterae from other planetary bodies; and a spectral assessment using Galileo NIMS data
Analysis of adenovirus VA RNAI structure and stability using compensatory base pair modifications
Adenovirus VA RNAs are short non-coding transcripts that assist in maintaining viral protein expression in infected cells. Six sets of mismatch and compensatory base pair mutants of VA RNAI were examined by gel mobility and RNA UV melting to assess the contribution of each structural domain to its overall structure and stability. Each domain of VA RNAI was first assigned to one of two apparent unfolding transitions in the wild-type melting profile. The Terminal Stem and Central Domain unfold in a single cooperative apparent transition with an apparent Tm of ∼60°C. In contrast, the Apical Stem unfolds independently and with much higher apparent Tm of ∼83°C. Remarkably, this domain appears to behave as an almost entirely autonomous unit within the RNA, mirroring the functional division within the RNA between PKR binding and inhibition. The effects of mismatch and compensatory mutations at five of the six sites on the RNA melting profile are consistent with proposed base pairing and provide further validation of the current secondary structure model. Mutations in the Central Domain were tested in PKR inhibition assays and a component of the VA RNAI Central Domain structure essential for PKR inhibitory activity was identified
West-Nile virus replicon particles infect 293T cells expressing DC-SIGNR
West-Nile virus (WNV) is an arbovirus usually transmitted to humans via a mosquito vector. Infections commonly result in febrile symptoms while rare severe neuroinvasive cases may result in encephalitis or meningitis. Studies have shown that WNV infection efficiency is enhanced by expression of DC-SIGNR on target cells, which normally do not express DC-SIGNR. To investigate WNV tropism, we established 293T kidney epithelial cell lines that stably express vector, DC-SIGNR and mutants of DC-SIGNR that lack the entire carbohydrate-recognition domain (CRD) or lack the C-terminal half of the CRD. We demonstrate successful surface expression of DC-SIGNR and its mutants from stablytransfected 293T cells, but not vector-transfected 293T cells. Further, we show that monoclonal antibody 120604 which binds specifically to the DC-SIGNR CRD binds to DCSIGNR expressing 293T cells, but not to vector nor any of the DC-SIGNR mutants expressing cells. Virus replicon particles (VRPs), replication-incompetent viral particles containing necessary structural proteins for infection and a viral plasmid including a GFP reporter are used to safely and conveniently study viral entry. Entry assays using WNV (NY99) VRPs as well as a variant of WNV (NY99) which contains the beta-lactamase enzyme show significant entry into DC-SIGNR expressing cell lines, but not in controls that do not express DC-SIGNR. Additionally, we show that WNV VRPs do not enter DC-SIGNR expressing cells that lack the CRD or the C-terminal half of the CRD suggesting that the Cterminal half of the CRD is required for successful entry of WNV via DC-SIGNR. Future experiments may be able to shed light on which amino acids are required for entryhttps://openriver.winona.edu/urc2018/1057/thumbnail.jp
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