Translation of mRNA injected into Xenopus oocytes is specifically inhibited by antisense RNA.

The bacteriophage SP6 promoter and RNA polymerase were used to synthesize sense and antisense RNAs coding for the enzymes thymidine kinase (TK) and chloramphenicol acetyl transferase (CAT). Injection of antisense CAT RNA into frog oocytes inhibited expression of sense CAT mRNA. Similarly, antisense TK RNA inhibited expression of sense TK mRNA. Antisense RNAs were stable in oocytes and had no detectable effect on either the expression of endogenous proteins or on the expression of nonhomologous RNA transcripts. CAT activity expressed from a plasmid transcribed in the oocyte nucleus was also inhibited by antisense RNA injected into the oocyte cytoplasm. The data suggest that antisense RNA will be useful in identifying the function of specific mRNA sequences during early development of the frog

Primitive erythropoiesis in early chick embryogenesis. II. Correlation between hemoglobin synthesis and the mitotic history.

Primitive erythroblasts in the circulating blood of the chick embryo continue to divide while synthesizing hemoglobin (Hb). Hb measurements on successive generations of erythroblasts show that there is a progressive increase in the Hb content of both interphase and metaphase cells. Furthermore, for any given embryo the Hb content of metaphase cells is always significantly greater than that of interphase cells. The distribution of Hb values for metaphase cells suggests that there are six Hb classes corresponding to the number of cell cycles in the proliferative phase. The location of erythroblasts in the cell cycle was determined by combining Feulgen cytophotometry with thymidine radioautography on the same cells. Measurements of the Hb content for erythroblasts in different compartments of the cell cycle (G1, S, G2, and M) show a progressive increase through the cycle. Thus, the amount of Hb per cell is a function of the number of cell divisions since the initiation of Hb synthesis and, to a lesser degree, the stage of the cell cycle. Earlier generations of erythroblasts synthesize Hb at a faster rate than the terminal generation. Several models have been proposed to explain these findings

Human Factor Associations with Safety Events in Radiation Therapy

One important connection for all human beings is that we have a shared need for health care and are at some risk of experiencing medical error. Errors documented in the field of radiation therapy have included tragic levels of suffering and even death from preventable mistakes. Efforts to improve patient safety include an approach called incident learning that makes use of information about known errors to inform safetyimprovement strategy. The complexity of human contributing factors challenges those safety improvements. The problem addressed by this dissertation study is that radiation therapy puts patients at risk, and the incident learning systems designed to inform safety improvements have yet to be optimized through a human factors framework. The Human Factors Analysis Classification System, a validated system utilized to categorize human contributing factors to error, was utilized in conjunction with a radiotherapy-specific list of distinct error types, such as treatment planning and quality assurance to classify a diverse international sample of radiotherapy safety events. The goal of this research was to discover predictive patterns of human factors contributing to radiotherapy incidents. Associations were uncovered between human contributing factors to error. Supervisory failures are linked to erroneous decision making and to unsafe environmental preconditions. Predictive associations between human factors and radiation therapy error types were discovered as well. Treatment-planning errors are associated with a specific kind of skill-based error that involves a lack of mindfulness. Quality assurance events are associated with certain supervisory and decision-type errors. Image-guidance errors are associated with perception failures and to failures at the human-computer interface. These associations incorporate a human factors framework and have direction for effective risk mitigation strategies

Effective constructions in plethysms and Weintraub's conjecture

We give a short proof of Weintraub's conjecture by constructing explicit highest weight vectors in the symmetric power of an even exterior power

A systematic review of treatments for Impulse Control Disorders and related behaviours in Parkinson's Disease

Impulse Control Disorders (ICDs) are a set of behaviours characterised by impulsivity despite known harm. Related to ICDs is the dopamine dysregulation syndrome (DDS), which is characterised by an addiction-like consumption of dopaminergic medication and punding. These behaviours all have an increased prevalence in Parkinson׳s disease (PD). The aim of this review is to identify treatments available for patients suffering from ICDs, DDS and punding in PD. Searches of The Cochrane Controlled Trials Register, Embase, Medline and PsychInfo were conducted, using the entire timescale available. Seven out of the 688 papers retrieved met the inclusion criteria and were considered in this systematic review. One class I study, one class II study, and five class IV studies were identified. All studies demonstrated a positive effect on ICDs in PD. Research in this field is still in its early stages. At present, there is insufficient evidence to recommend any treatment over another. There is a need for more methodologically robust research, using larger, more generalisable samples, randomisation and meaningful follow-up periods. In addition, the use of a validated outcome measures should be implemented in future research efforts

Evidence for Accretion in the High-resolution X-ray Spectrum of the T Tauri Star System Hen 3-600

We present high-resolution X-ray spectra of the multiple T Tauri star system Hen 3-600, obtained with the High Energy Transmission Grating Spectrograph on the Chandra X-ray Observatory. Two binary components were detected in the zeroth-order image. Hen 3-600-A, which has a large mid-infrared excess, is a 2-3 times fainter in X-rays than Hen 3-600-B, due to a large flare on B. The dispersed X-ray spectra of the two primary components overlap spatially; spectral analysis was performed on the combined system. Analysis of the individual spectra was limited to regions where the contributions of A and B can be disentangled. This analysis results in two lines of evidence indicating that the X-ray emission from Hen 3-600 is derived from accretion processes: line ratios of O VII indicate that the characteristic density of its X-ray-emitting plasma is large; a significant component of low-temperature plasma is present and is stronger in component A. These results are consistent with results obtained from X-ray gratings spectroscopy of more rapidly accreting systems. All of the signatures of Hen 3-600 that are potential diagnostics of accretion activity -- X-ray emission, UV excess, H-alpha emission, and weak infrared excess -- suggest that its components represent a transition phase between rapidly accreting, classical T Tauri stars and non-accreting, weak-lined T Tauri stars.Comment: latex, 27 pages, 12 figures, 6 tables; accepted by Ap

Connection and coherence between and among European instruments in the private international law of obligations

This article considers points of connection and coherence between and among the Rome I Regulation, the Rome II Regulation, and Regulation 1215, and relevant predecessor instruments. The degree of consistency in aim, design and detail of conflict of laws rules is examined, vertically (between/among consecutive instruments) and horizontally (across cognate instruments). Symbiosis between instruments is explored, as is the interrelationship between choice of court and choice of law. Disadvantaged parties, and the cohesiveness of their treatment under the Regulations, receive particular attention