12610514
Purinergic Receptor Functionality Is Necessary for Infection of Human Hepatocytes by Hepatitis Delta Virus and Hepatitis B Virus
Hepatitis B virus (HBV) and hepatitis delta virus (HDV) are major sources of acute and chronic hepatitis. HDV requires the envelope proteins of HBV for the processes of assembly and infection of new cells. Both viruses are able to infect hepatocytes though previous studies have failed to determine the mechanism of entry into such cells. This study began with evidence that suramin, a symmetrical hexasulfated napthylurea, could block HDV entry into primary human hepatocytes (PHH) and was then extrapolated to incorporate findings of others that suramin is one of many compounds that can block activation of purinergic receptors. Thus other inhibitors, pyridoxal-phosphate-6-azophenyl-2′,4′-disulfonate (PPADS) and brilliant blue G (BBG), both structurally unrelated to suramin, were tested and found to inhibit HDV and HBV infections of PHH. BBG, unlike suramin and PPADS, is known to be more specific for just one purinergic receptor, P2X7. These studies provide the first evidence that purinergic receptor functionality is necessary for virus entry. Furthermore, since P2X7 activation is known to be a major component of inflammatory responses, it is proposed that HDV and HBV attachment to susceptible cells, might also contribute to inflammation in the liver, that is, hepatitis.
33501684
Tumor virus ribonucleic acid directed deoxyribonucleic acid synthesis: nucleotide sequence at the 5' terminus of nascent deoxyribonucleic acid.
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.
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.
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.
6962773
Heritability of Wisconsin Card Sorting Test (WCST) and Stroop Color-Word Test performance in normal individuals: implications for the search for endophenotypes.
A surge in the search for endophenotypes for psychiatric disorders has occurred in the past several years. An important criterion of an endophenotype is that it is heritable. Two of the most widely used executive cognitive functioning measures are the Wisconsin Card Sorting Test (WCST) and the Stroop Color-Word Test. Each has been considered as a possible endophenotype. However, research on the heritability of each of these measures is sparse, and in the case of the WCST, mixed. As part of a pilot twin study examining cognitive functioning and personality in adults, the WCST and the Stroop were administered to 80 monozygotic and 29 dizygotic twin pairs screened for absence of neurological disease and head injury. Results replicated and extended previous findings for moderate heritability of Stroop performance. However, the WCST showed little evidence of genetic influence, suggesting that it might not meet one of the criteria for an endophenotype.
33681413
The impact of manual handling on nursing home resident mobility during transfers on and off furniture: a systematic review.
This systematic review aimed to investigate the impact of staff manual handling practices and physical training interventions on nursing home residents' ability to transfer on and off furniture. Key words and subject headings were used to search databases for English language studies published after 1994. Ten studies met the inclusion criteria. Studies of physical activity interventions indicated that physical activity training will benefit residents' transfer ability. One study examined the effect of a safe manual handling program on resident quality care outcomes. Further research is required into the nature and impact of the assistance provided by staff to residents during transfers. Innovative and sustainable approaches to safe manual handling that promote resident mobility are needed.
21804822
Protein biofortified sorghum: effect of processing into traditional african foods on their protein quality.
Protein biofortification into crops is a means to combat childhood protein-energy malnutrition (PEM) in developing countries, by increasing the bioavailability of protein in staple plant foods and ensuring sustainability of the crop. Protein biofortification of sorghum has been achieved by both chemically induced mutation and genetic engineering. For this biofortification to be effective, the improved protein quality in the grain must be retained when it is processed into staple African foods. Suppression of kafirin synthesis by genetic engineering appeared to be superior to improved protein digestibility by chemical mutagenesis, because both the lysine content and protein digestibility were substantially improved and maintained in a range of African foods. For the genetically engineered sorghums, the protein digestibility corrected amino acid score was almost twice that of their null controls and considerably higher than the high protein digestibility sorghum type. Such protein biofortified sorghum has considerable potential to alleviate PEM.
3707230
Personality trait differences in boys and girls with clinical or sub-clinical diagnoses of conduct disorder versus antisocial personality disorder.
This study tested differences in personality traits measured by the Multidimensional Personality Questionnaire (MPQ) in a community sample of adolescents with definite or probable conduct disorder (CD) diagnoses that did not progress to a diagnosis of antisocial personality disorder (ASPD) by early adulthood (n=43), those with definite or probable ASPD that persisted into early adulthood (n=68), or controls with neither a CD nor an ASPD diagnosis (n=716) to examine whether antisocial behaviour disorders that differed in course were associated with differences in personality traits. As expected, boys and girls with ASPD were significantly different from controls on constraint, and those with ASPD were significantly lower on constraint than those with only CD. The results suggest that individual differences in certain personality traits may contribute to differences in the type of antisocial behaviour disorder that emerges and thereby to the course of antisocial behaviour.