44845847
Human hepatitis delta virus: an agent with similarities to certain satellite RNAs of plants.
One of the most intriguing aspects of hepatitis delta virus (HDV) is that, even though it is a naturally occurring infectious agent of human beings, it nevertheless shows a number of remarkable similarities to viroids, the subviral agents of plants that are considered elsewhere in this volume. The recognition and exploitation of this analogy has been a major contributor to studies of HDV genome replication. This review will concentrate on the structure of the HDV genome and the mechanism by which the genome is replicated, with special emphasis on similarities to the viroids. The review will not consider in any depth other important aspects of HDV, such as the assembly of genomes into virus particles, experimental transmission, host responses, or epidemiology. For such information the reader is directed to other more extensive reviews (Lai 1995; Purcell and Gerin 1996; Hadziyannis 1997; Margolis et al. 1997). However, to put this review in perspective, we will present a limited amount of background material.
28296194
Retrovirus Genome Replication: Priming Specificities of Plus-Strand DNA Synthesis
SUMMARY The retroviral reverse transcriptase is a multifunctional protein. Not only does it contain both RNA- and DNA-directed DNA synthesis activities but also it contains an endonuclease activity necessary for the integration of viral RNA and a RNase H. This latter activity can reduce to oligoribonucleotides viral RNA that has been reverse transcribed into minus-strand DNA. However, during avian retrovirus genome replication it does this in a highly specific manner so as to generate a specific 12-base primer for plus-strand DNA synthesis. Even though many other oligoribonucleotides are also made there is an efficient selection of the specific primer followed by its efficient utilization in plus-strand DNA synthesis, and subsequent removal. We have used a reconstructed system to gain an understanding of the factors that contribute towards these observed specificities.
33501684
Tumor virus ribonucleic acid directed deoxyribonucleic acid synthesis: nucleotide sequence at the 5' terminus of nascent deoxyribonucleic acid.
12985098
A note on the incorporation of amino acids by hamster embryo cells in monolayer culture.
11606238
Hepatitis delta virus.
Hepatitis delta virus (HDV) is a sub-viral agent that is dependent for its life cycle on hepatitis B virus (HBV). The help it obtains from HBV is limited to the sharing of envelope proteins. These proteins are needed to facilitate the assembly of the HDV genome into new virus particles, and in turn, to allow the attachment and entry of HDV into new host cells. In other respects, the replication of the small single-stranded circular RNA genome of HDV is independent of HBV. HDV genome replication produces two forms of a RNA-binding protein known as the long and small delta antigens (Ag). All other proteins needed for HDV genome replication, especially the RNA-directed RNA polymerase activity, are provided by the host cell. This mini-review article is a mixture of personal perspective and speculations about the future of HDV research. It starts with a brief overview of HDV and its replication, notes some of the major unresolved questions, and directs the interested reader to more detailed reviews.
27724235
Avian RNA tumor virus DNA before and after integration into the host genome.
32905395
On the precipice of great things: the current state of UK nurse education.
The significant policy changes in UK health care over the past decade have led to a consequent shift in the delivery of nurse education to ensure the development and sustainability of a knowledgeable nursing workforce. One of the most recent, radical and important initiatives is Modernising Nursing Careers, which outlined four key priority areas for nursing, all of which have implications for nurse education. In light of this initiative, we explore the extent to which the modernisation of nursing careers is rhetoric or reality for UK nurse education - we are on the precipice of great change. To facilitate this, we move chronologically through the issues of recruitment and access; pre-registration preparation; and post-qualification education and careers. In discussing these issues, we demonstrate that more changes are needed to produce nurses who are flexible, visionary and prepared to take risks. We suggest that vision, leadership and strong realignment with health priorities are needed to bring nurse education to a point where nurses are truly prepared for the demands of a 21st century health service.
43587475
Development of substance dependence in two delinquency subgroups and nondelinquents from a male twin sample.
OBJECTIVE
The effect of delinquency subtype on the development of substance dependence symptoms was examined. It was proposed that early-onset delinquents possess characteristics that increase their likelihood of developing substance dependence problems earlier and more rapidly than late-onset delinquents and nondelinquents.


METHOD
The development of alcohol, nicotine, and cannabis dependence symptoms (DSM-III-R) was examined over a 6-year period of adolescence (age 11-17) among 36 early-onset delinquent, 86 late-onset delinquent, and 25 nondelinquent boys from a large epidemiological twin sample. Multilevel/random coefficients models were used to compare groups on the rate of growth in number of symptoms over time.


RESULTS
As expected, early-onset delinquents showed an earlier onset and a faster rate of increase in the number of cannabis and nicotine dependence symptoms than late-onset delinquents and controls. Both delinquent groups had a more rapid increase in alcohol dependence symptoms than controls.


CONCLUSIONS
The data showed that early-onset delinquency is associated with earlier onset of substance use disorder symptoms and more rapid acceleration of problems with drugs than late-onset delinquency. Treatments for boys with early-onset delinquency should account for their increased risk for drug use problems in adolescence and the potential effects of those problems on the course of antisocial behavior.
16183837
The modifying effect of the building envelope on population exposure to PM2.5 from outdoor sources
A number of studies have estimated population exposure to PM2.5 by examining modeled or measured outdoor PM2.5 levels. However, few have taken into account the mediating effects of building characteristics on the ingress of PM2.5 from outdoor sources and its impact on population exposure in the indoor domestic environment. This study describes how building simulation can be used to determine the indoor concentration of outdoor-sourced pollution for different housing typologies and how the results can be mapped using building stock models and Geographical Information Systems software to demonstrate the modifying effect of dwellings on occupant exposure to PM2.5 across London. Building archetypes broadly representative of those in the Greater London Authority were simulated for pollution infiltration using EnergyPlus. In addition, the influence of occupant behavior on indoor levels of PM2.5 from outdoor sources was examined using a temperature-dependent window-opening scenario. Results demonstrate a range of I/O ratios of PM2.5, with detached and semi-detached dwellings most vulnerable to high levels of infiltration. When the results are mapped, central London shows lower I/O ratios of PM2.5 compared with outer London, an apparent inversion of exposure most likely caused by the prevalence of flats rather than detached or semi-detached properties.
24035579
Substance Use Disorders and Cluster B Personality Disorders: Physiological, Cognitive, and Environmental Correlates in a College Sample
Substance use disorders (SUDs) and Cluster B personality disorders (PDs) are both marked by impulsivity and poor behavioral control and may result in part from shared neurobiological or executive cognitive functioning deficits. To examine the potential utility of such models in explaining variance in SUDs and PDs at the lower end of symptom expression and impairment, 123 (73 female) volunteer college students were administered 2 measures of executive cognitive functioning; a task assessing autonomic reactivity to aversive noise blasts; a life events and a peer substance use measure; and structured clinical interviews to assess symptoms of substance abuse/dependence and antisocial, borderline, histrionic, and narcissistic PDs. As expected, symptoms of SUDs and PDs were significantly positively correlated. Antisocial PD, alcohol and cannabis use disorder symptoms were significantly positively related to proportion of friends who use alcohol and drugs regularly and drug use among romantic partners. Number of negative life events was positively related to PD symptoms and to alcohol use disorder symptoms. Executive cognitive functioning was not related to SUD and PD symptoms in the expected direction. Findings suggest that, among higher functioning young adults, environmental factors may be particularly relevant to our understanding of SUDs and certain PDs.
8674073
Children, health and gender: recognition in nursing research?
AIM
This paper examines the hitherto mostly unrecognised relationship between gender, health and children; its significance for nursing practice and how it has been considered in nursing research.


BACKGROUND
Holistic nursing practice with children requires adequate assessment and consideration of all potential influences on children's lives. Socioeconomic disparities have received widespread attention and gender inequalities in adult health have been studied in some depth. The links between gender, health and children, however, have received little consideration. The paper first considers this context in depth; it then applies the context to research in practice.


DESIGN
Systematic review.


METHODS
A systematic literature search was undertaken on four mainstream nursing research journals over 38 months up to February 2007. A total of 567 articles met the key word searches. Duplicates, opinion pieces and articles not focusing on children were removed. The remaining 23 nursing studies relevant to child health were examined for their gender sensitivity.


RESULTS
Full consideration of gender issues was found largely to be absent in nursing research on children. Eight studies gave specific consideration to gender relevance, where boys and girls may have responded differently to care. Only six studies specifically addressed gender sensitivity. Allowing children a voice, however, was a strength in these studies, with 18 reflecting children's views directly.


CONCLUSIONS
Major gaps still exist in research and theorisation relating to children, health and gender. These need to be acknowledged and investigated, particularly in relation to how they might impact on nursing care.


RELEVANCE TO CLINICAL PRACTICE
Nursing practice and research needs to account for all potential health issues, of which gender may often be important.