2,022 research outputs found
Passive chevron replicator
There is described a passive replicator device to be used in magnetic bubble domain systems. The replicator is passive, i.e., does not require an active element such as a current source or the like, and both propagates and replicates bubble domains. In a preferred embodiment, the replicator uses chevron type elements arranged in an appropriate pattern so as to interact with a pair of propagation paths wherein bubble domains are propagated. A bubble in one propagation path is routinely transferred therealong and, concurrently, replicated by the instant device into another propagation path. A plurality of elements arranged in juxtaposition to the chevrons assists in controlling the propagation of the bubbles through the respective propagation paths and, at the appropriate time, provides a cutting action wherein a bubble which is elongated between the chevrons of the two propagation paths is split into two separate bubbles
Yeast Rrp14p is required for ribosomal subunit synthesis and for correct positioning of the mitotic spindle during mitosis
Here we report that Rrp14p/Ykl082p is associated with pre-60S particles and to a lesser extent with earlier 90S pre-ribosomes. Depletion of Rrp14p inhibited pre-rRNA synthesis on both the 40S and 60S synthesis pathways. Synthesis of the 20S precursor to the 18S rRNA was largely blocked, as was maturation of the 27SB pre-rRNA to the 5.8S and 25S rRNAs. Unexpectedly, Rrp14p-depleted cells also showed apparently specific cell-cycle defects. Following release from synchronization in S phase, Rrp14p-depleted cells uniformly arrested in metaphase with short mitotic spindles that were frequently incorrectly aligned with the site of bud formation. In the absence of Bub2p, which is required for the spindle orientation checkpoint, this metaphase arrest was not seen in Rrp14p-depleted cells, which then arrested with multiple buds, several SPBs and binucleate mother cells. These data suggest that Rrp14p may play some role in cell polarity and/or spindle positioning, in addition to its function in ribosome synthesis
Time to establish multidisciplinary childhood cancer survivorship programs in Korea
Improved treatment strategies and better supportive care have resulted in increased survival rates for childhood cancers. However, most of the survivors may have complex, long-term health issues. In 2004, Childhood Cancer Survivorship Study of the United States confirmed that both survivors and the medical community need to be educated about the late effects of childhood cancer treatment. Korea, with an estimated number of childhood cancer survivors of 20,000 to 25,000, faces similar challenges that the United States had experienced earlier. Despite of the tight budgetary situation on the part of government and hospitals, nationwide cohort study for Korean childhood cancer survivors was proposed and the versions of instruments to measure the quality of life of childhood cancer survivors were already validated. Nationwide registry of long-term survivors as well as the multi-center study is to be developed not only for the care of the survivors but also to raise the patient's awareness of the importance of regular follow-up. In addition to education of primary care providers regarding the survivorship, the need for special education program in the school system is emphasized
Apō ptosis
Apō ptosis is a book of poetry that questions the fragmentation and alienation between the different levels of the human self: the micromolecular and the macromolecular, the biological and the metaphysical, the mythological and scientific. Resisting nihilistic principles of rationalizing humanness, the poems explore human embodiment by re-connecting the self with its micro- and macromolecular surroundings by blending and juxtaposing all levels of human existence, invisible and visible, and setting up a conversation between them. The work is divided in two sections. In the first section, a long-form poem, a female speaker considers what constitutes her ‘self’. Engaging with the story of Helen of Troy, she encounters the phenomena of the undiscovered, the submerged, and the dissimulated that form the self beyond what is physically embodied in the moment; a self just slightly out of time and space, and possibility. The second section is a set of lyrical poems in which the speaker remembers, encounters, and grieves over lost, discovered and never possible parts of her ‘self’ that emerge through encounters with memory, others, and the environment – the macro- and the micromolecular. Grounded in Heidegger's notion of defamiliarizing the familiar and drawing attention to the invisible, the poems create a cohesion between the disparate levels of self in a space where an unfragmented self may exist unrecognized, an in-between space of convergence
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Stroke impact on mortality and psychologic morbidity within the Childhood Cancer Survivor Study.
BackgroundPoor socioeconomic and health-related quality of life (HRQOL) outcomes in survivors of childhood cancer can lead to distress and overall negatively impact the lives of these individuals. The current report has highlighted the impact of stroke and stroke recurrence on mortality, psychological HRQOL, and socioeconomic outcomes within the Childhood Cancer Survivor Study (CCSS).MethodsThe CCSS is a retrospective cohort study with longitudinal follow-up concerning survivors of pediatric cancer who were diagnosed between 1970 and 1986. Mortality rates per 100 person-years were calculated across 3 periods: 1) prior to stroke; 2) after first stroke and before recurrent stroke; and 3) after recurrent stroke. Socioeconomic outcomes, the standardized Brief Symptoms Inventory-18, the Medical Outcomes Study 36-Item Short Form Health Survey, and the CCSS-Neurocognitive Questionnaire also were assessed.ResultsAmong 14,358 participants (median age, 39.7 years), 224 had a stroke after their cancer diagnosis (single stroke in 161 patients and recurrent stroke in 63 patients). Based on 2636 deaths, all-cause late mortality rates were 0.70 (95% CI, 0.68-0.73) prior to stroke, 1.03 (95% CI, 0.73-1.46) after the first stroke, and 2.42 (95% CI, 1.48-3.94) after the recurrent stroke. Among 7304 survivors, those with stroke were more likely to live with a caregiver (single stroke odds ratio [OR], 2.3 [95% CI, 1.4-3.8]; and recurrent stroke OR, 5.3 [95% CI, 1.7-16.8]) compared with stroke-free survivors. Stroke negatively impacted task efficiency (single stroke OR, 2.4 [95% CI, 1.4-4.1] and recurrent stroke OR, 3.3 [95% CI, 1.1-10.3]) and memory (single stroke OR, 2.1 [95% CI, 1.2-3.7]; and recurrent stroke OR, 3.5 [95% CI, 1.1-10.5]).ConclusionsStroke and stroke recurrence are associated with increased mortality and negatively impact HRQOL measures in survivors of pediatric cancer
Preferences for long-term follow-up care in childhood cancer survivors
Follow-up care is important for childhood cancer survivors to facilitate early detection and treatment of late effects. We aimed to describe preferences for different organisational aspects and models of follow-up care among Swiss childhood cancer survivors, and characteristics associated with preferences for different models. We contacted 720 survivors aged 18+ years, diagnosed with cancer after 1990 (age 0-16 years), registered in the Swiss Childhood Cancer Registry (SCCR), and Swiss resident, who previously participated in a baseline survey. They received questionnaires to assess attendance and preferences for follow-up (rated on 4-point scales, 0-3). Clinical information was available from the SCCR. Survivors (n = 314: response rate 43.6%; 47.8% still attended follow-up) rated clinical reasons for follow-up higher than supportive reasons (p < .001). They rated checking for cancer recurrence (mean = 2.78, SD = 0.53) and knowing about risks for my children most important (mean = 2.22, SD = 0.83). They preferred to attend a children's hospital (mean = 1.94, SD = 1.11), adult hospital (mean = 1.86, SD = 0.98) or general practitioner (mean = 1.86, SD = 1.01) rather than a central specialised late effects clinic (mean = 1.25, SD = 1.06, p < .001), and be seen by paediatric (mean = 2.24, SD = 0.72) or medical oncologist (mean = 2.17, SD = 0.69). Survivors preferred decentralised clinic-based follow-up, rather than one central specialised late effects clinic. Survivors' preferences should be considered to ensure future attendance
Obesity and metabolic syndrome in adolescent survivors of standard risk childhood acute lymphoblastic leukemia in Saudi Arabia
This study estimated prevalence of unhealthy weight status and metabolic syndrome (MS) amongst Saudi survivors of standard risk ALL. Procedure. We recruited 56 survivors, mean age 13.4 years (SD 4.1), a mean of 9.1 years (SD 4.1) postdiagnosis. The BMI for age was used to define weight status relative to national (Saudi) and international (Cole et al., Cole-IOTF, WHO, and CDC) reference data. We measured body composition by dualenergy X-ray absorptiometry (DXA), waist circumference, blood pressure, lipid profile (HDL-C, Triglycerides), fasting glucose and insulin. Results. According to international definitions based on BMI for age, around half of the sample had unhealthy weight status. All of the approaches based on BMI for age underestimated overfatness, present in 27/51 (53%) of the sample according to DXA. Prevalence of MS was 7.1% (3/42 of those over 9-years old) and 5.4% (3/56) by applying the International Diabetes Federation (IDF) definition and National Cholesterol Education Program Third Adult Treatment panel Guidelines (NCEP III), respectively. However, MS by the NCEP III definition was present in 19% of the overweight and obese survivors and 7.1% of the sample had at least two of the components of MS. Conclusion. Unhealthy body weight and overfatness may be common amongst adolescent Saudi survivors of standard risk ALL, though overweight and obesity may be no more common than in the general Saudi adolescent population. Defining weight status using BMI underestimates overfatness. Ideally, body composition and cardiometabolic risk factors should be monitored at late effects clinics. Pediatr Blood Cancer 2012;59: 133–137. 2011 Wiley Periodicals, Inc
Sumoylation of the THO complex regulates the biogenesis of a subset of mRNPs
International audienceAssembly of messenger ribonucleoparticles (mRNPs) is a pivotal step in gene expression, but only a few molecular mechanisms contributing to its regulation have been described. Here, through a comprehensive proteomic survey of mRNP assembly, we demonstrate that the SUMO pathway specifically controls the association of the THO complex with mRNPs. We further show that the THO complex, a key player in the interplay between gene expression, mRNA export and genetic stability, is sumoylated on its Hpr1 subunit and that this modification regulates its association with mRNPs. Altered recruitment of the THO complex onto mRNPs in sumoylation-defective mutants does not affect bulk mRNA export or genetic stability, but impairs the expression of acidic stress-induced genes and, consistently, compromises viability in acidic stress conditions. Importantly, inactivation of the nuclear exosome suppresses the phenotypes of the hpr1 non-sumoylatable mutant, showing that SUMO-dependent mRNP assembly is critical to allow a specific subset of mRNPs to escape degradation. This article thus provides the first example of a SUMO-dependent mRNP-assembly event allowing a refined tuning of gene expression, in particular under specific stress conditions
A cluster of ribosome synthesis factors regulate pre-rRNA folding and 5.8S rRNA maturation by the Rat1 exonuclease
The 5′-exonuclease Rat1 degrades pre-rRNA spacer fragments and processes the 5′-ends of the 5.8S and 25S rRNAs. UV crosslinking revealed multiple Rat1-binding sites across the pre-rRNA, consistent with its known functions. The major 5.8S 5′-end is generated by Rat1 digestion of the internal transcribed spacer 1 (ITS1) spacer from cleavage site A(3). Processing from A(3) requires the ‘A(3)-cluster' proteins, including Cic1, Erb1, Nop7, Nop12 and Nop15, which show interdependent pre-rRNA binding. Surprisingly, A(3)-cluster factors were not crosslinked close to site A(3), but bound sites around the 5.8S 3′- and 25S 5′-regions, which are base paired in mature ribosomes, and in the ITS2 spacer that separates these rRNAs. In contrast, Nop4, a protein required for endonucleolytic cleavage in ITS1, binds the pre-rRNA near the 5′-end of 5.8S. ITS2 was reported to undergo structural remodelling. In vivo chemical probing indicates that A(3)-cluster binding is required for this reorganization, potentially regulating the timing of processing. We predict that Nop4 and the A(3) cluster establish long-range interactions between the 5.8S and 25S rRNAs, which are subsequently maintained by ribosomal protein binding
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