37632421
Replication of human hepatitis delta virus: influence of studies on subviral plant pathogens.
Publisher Summary This chapter discusses how the studies of the subviral pathogens of plants have influenced and continue to influence the nature of human hepatitis delta virus (HDV) research. Studies of the plant viroids and the plant satellite RNAs and viruses have had major effects, both direct and indirect, on the understanding of HDV. Hepatitis B virus (HBV) replicates in the liver and releases its DNA-containing particles into the bloodstream. The pathogenicity associated with HDV replication can be discussed at different levels. At the outset, HDV infection was considered to be a major risk factor for increased levels of liver damage. It seemed to be an agent that, in collaboration with HBV, could make HBV infections much more likely to lead to a fulminant hepatitis and to death. There are also data indicating that infection by certain genotypes of HDV can be, especially pathogenic. In an infected primate or woodchuck, HDV replication is typically associated with that of the helper hepadnavirus. Such a combination can be pathogenic. The presence of a host-immune response to either or both of these viruses can be associated with pathogenesis. The chapter discusses various initial application of molecular virology.
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.
12985098
A note on the incorporation of amino acids by hamster embryo cells in monolayer culture.
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.
27724235
Avian RNA tumor virus DNA before and after integration into the host genome.
32584830
Genetic and Environmental Influences on Psychopathy Trait Dimensions in a Community Sample of Male Twins
Psychopathy appears to be comprised of two broad dimensions: impulsivity/antisocial behavior and interpersonal detachment/callousness. This study examined the extent to which variance in these 2 psychopathy trait dimensions was associated with common or unique genetic, shared, and nonshared environmental factors in two independent samples of reared together 16–18-year-old male twins. One sample included 142 monozygotic (MZ) and 70 dizygotic (DZ) pairs; the other sample included 128 MZ and 58 DZ pairs. Boys completed the Minnesota Temperament Inventory (MTI), a 19-item measure that contains separate subscales: Antisocial and Detachment. Variance in the Antisocial and Detachment scales was associated with additive genetic factors and neither scale was associated with shared environmental factors. As expected, the bivariate biometric analysis suggested genetic influence on the covariance of the scales. The results are consistent with theoretical models of psychopathy that posit some independence in the etiology of the two major trait dimensions of psychopathy.
24529809
Multiple-electrode nerve cuffs for low-velocity and velocity-selective neural recording
In the paper, a method using multiple-electrode nerve cuffs is presented that enables electroneurographic signals (ENG) to be recorded selectively by action potential velocity. The theory uses a one-dimensional model of the electrodes in the cuff. Using this model, the transfer function for a single tripole is derived, and it is shown that more than one tripole signal can be recorded from within a cuff. When many tripole signals are available and are temporally aligned by artificial delays and summed, there is a significant increase in the amplitude of the recorded action potential, depending on the cuff length and the action potential velocity, with the greatest gain occurring for low velocities. For example, a cuff was considered that was constrained by surgical considerations to 30 mm between the end electrodes. For action potentials with a velocity of 120 ms−1, it was shown that, as the number of tripoles increased from one, the peak energy spectral density of the recorded output increased by a factor of about 1.6 with three tripoles, whereas, for 20 ms−1, the increase was about 19, with ten tripoles. The time delays and summation act as a velocity-selective filter. With consideration of the energy spectral densities at frequencies where are maximum (to give the best signal-to-noise ratio), the tuning curves are presented for these velocity-selective filters and show that useful velocity resolution is possible using this method. For a 30 mm cuff with nine tripoles, it is demonstrated that it is possible to resolve at least five distinct velocity bands in the range 20–120 ms−1.
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.
24886138
Comparison and characteristics of motor vehicle accident (MVA) and non-MVA driving fears.
Prior research has revealed the diagnostic complexity among people who report driving fears. However, the focus on survivors of motor vehicle accidents (MVAs) and diagnostic samples may have inadvertently led to a relative neglect of the broader driving-fearful population. No studies could be located that compared MVA survivors with those who had not experienced an MVA. The aim of the present study was to address these deficits by comparing the characteristics of MVA and non-MVA driving-fearfuls and also exploring a range of characteristics associated with driving fears. One hundred and ninety media-recruited driving-fearfuls completed a questionnaire that assessed severity of anxiety and avoidance associated with a variety of driving situations. It was found that fear levels were similar to samples of driving phobics and MVA victims. There were no significant differences between MVA and non-MVA respondents on various measures of fear severity. In addition, the sample rated a high level of anxiety when driving with someone who criticizes their driving. Implications of the findings are discussed, along with suggestions for assessment and treatment of those with driving-related fears.
12307738
Screening for disinhibited disorder cases in a college population: Performance of the SMAST, DAST, SCID-II-Q, and PDQ-4.
Psychiatric disorders characterized by disinhibition--substance use disorders, antisocial personality disorder (PD), and borderline PD--represent a serious risk to the safety and health of college students. The ability of researchers and clinicians to identify students most at risk for disinhibited disorders associated with campus crime, violence, and self-harm depends on measures with strong evidence of diagnostic efficiency, yet data on the diagnostic efficiency of screening measures in college populations are lacking. The authors addressed this need by examining the diagnostic efficiency of commonly used screening measures for disinhibited disorders in a sample of 2,085 students, 79 of whom also completed diagnostic interviews. Results suggest that the diagnostic efficiency (e.g., sensitivity, specificity) of screening measures for substance use disorders and antisocial PD in college samples can be increased by making simple adjustments in screening cutoff criteria. Similar adjustments did not increase the diagnostic efficiency of the screening measure for borderline PD, and this suggested that certain screeners may best be aimed at ruling out disorders. This type of information offers users flexibility with which to tailor the screening threshold to serve different objectives.