Medical and nursing students perceived knowledge, attitudes, and practices concerning human immunodeficiency virus

Objective. To assess medical and nursing students’ knowledge, attitudes, and practices (KAP) regarding human immunodeficiency virus (HIV) in Fiji. Methods. A cross-sectional study of 275 medical and 252 nursing students that participated in a questionnaire survey on HIV KAP. Data was analysed according to their gender, program of study, and academic year. Results. The mean HIV knowledge (HK) and attitude scores were 16.0 and 41.3, respectively. Mean HK score was significantly higher in males compared to females. Significant positive correlations were found between HK and academic year for medical () and nursing () students and between HK and attitude scores (). The majority of students indicated fear in contracting HIV through clinical practice and felt that health care workers have the right to know a patients HIV status for their own safety. The majority would wear gloves to touch a patient if suspected of HIV. Conclusions. The study found a high level of HIV knowledge and positive attitude towards HIV patients. However, respondents also displayed negative attitudes and unacceptable practices probably due to fear. Training institutions need to ensure that students gain accurate knowledge on HIV especially on transmission routes to allay the fear of caring for HIV-infected patients.

Ross River virus disease activity associated with naturally occurring non-tidal flood events in Australia : A systematic review

Ross River virus (RRV) disease is the most common and widespread mosquito-borne disease in Australia, resulting in considerable health and economic cost to communities. While naturally occurring non-tidal flood events may enhance mosquito abundance, little is known about the impact of such events on RRV transmission. This paper critically reviews the existing evidence for an association between naturally occurring non-tidal flood events and RRV transmission. A systematic literature search was conducted on RRV transmission related to flooding and inundation from rain and riverine overflow. Overall, the evidence to support a positive association between flooding and RRV outbreaks is largely circumstantial, with the literature mostly reporting only coincidental occurrence between the two. However, for the Murray River, river flow and height (surrogates of flooding) were positively and significantly associated with RRV transmission. The association between non-tidal flooding and RRV transmission has not been studied comprehensively. More frequent flood events arising from climate change may result in increased outbreaks of RRV disease. Understanding the link between flood events and RRV transmission is necessary if resources for mosquito spraying and public health warnings are to be utilized more effectively and efficiently.

Inducible resistance to maize streak virus

Maize streak virus (MSV), which causes maize streak disease (MSD), is the major viral pathogenic constraint on maize production in Africa. Type member of the Mastrevirus genus in the family Geminiviridae, MSV has a 2.7 kb, single-stranded circular DNA genome encoding a coat protein, movement protein, and the two replication-associated proteins Rep and RepA. While we have previously developed MSV-resistant transgenic maize lines constitutively expressing ‘‘dominant negative mutant’’ versions of the MSV Rep, the only transgenes we could use were those that caused no developmental defects during the regeneration of plants in tissue culture. A better transgene expression system would be an inducible one, where resistance-conferring transgenes are expressed only in MSV-infected cells. However, most known inducible transgene expression systems are hampered by background or ‘‘leaky’’ expression in the absence of the inducer. Here we describe an adaptation of the recently developed INPACT system to express MSV-derived resistance genes in cell culture. Split gene cassette constructs (SGCs) were developed containing three different transgenes in combination with three different promoter sequences. In each SGC, the transgene was split such that it would be translatable only in the presence of an infecting MSV’s replication associated protein. We used a quantitative real-time PCR assay to show that one of these SGCs (pSPLITrepIII-Rb-Ubi) inducibly inhibits MSV replication as efficiently as does a constitutively expressed transgene that has previously proven effective in protecting transgenic maize from MSV. In addition, in our cell-culture based assay pSPLITrepIII-Rb-Ubi inhibited replication of diverse MSV strains, and even, albeit to a lesser extent, of a different mastrevirus species. The application of this new technology to MSV resistance in maize could allow a better, more acceptable product.

Using DNA as a drug - bioprocessing and delivery strategies

DNA may take a leading role in a future generation of blockbuster therapeutics. DNA has inherent advantages over other biomolecules such as protein, RNA and virus-like particles including safety, production simplicity and higher stability at ambient temperatures. Vaccination is the principal measure for preventing influenza and reducing the impact of pandemics; however, vaccines take up to 8-9 months to produce, and the global production capacity is woefully low. With production times as short as 2 weeks, improved safety and stability, bioprocess engineering developments, and the ability to perform numerous therapeutic roles, DNA has the potential to meet the demands of emerging and existing diseases. DNA is experiencing sharp growths in demand as indicated by its use in gene therapy trials and DNA vaccine related patents. Of particular interest for therapeutic use is plasmid DNA (pDNA), a form of non-genomic DNA that makes use of cellular machinery to express proteins or antigens. The production stages of fermentation and downstream purification are considered in this article. Forward looking approaches to purifying and delivering DNA are reported, including affinity chromatography and nasal inhalation. The place that pDNA may take in the preparation for and protection against pandemics is considered. If DNA therapeutics and vaccines prove to be effective, the ultimate scale of production will be huge which shall require associated bioprocess engineering research and development for purification of this large, unique biomolecule.

DNA molecules and human therapeutics

Nucleic acid molecules are championing a new generation of reverse engineered biopharmaceuticals. In terms of potential application in gene medicine, plasmid DNA (pDNA) vectors have exceptional therapeutic and immunological profiles as they are free from safety concerns associated with viral vectors, display non-toxicity and are simpler to develop. This review addresses the potential applications of pDNA molecules in vaccine design/development and gene therapy via recombinant DNA technology as well as a staged delivery mechanism for the introduction of plasmid-borne gene to target cells via the nasal route.

An evaluation of potential candidate genes involved in salinity tolerance in striped catfish (Pangasianodon hypopthalmus) using an RNA-SEQ approach

The project investigated the molecular response of Tra catfish (Pangasianodon hypophthalmus) to elevated salinity conditions. We employed Next generation sequencing platform to evaluate differential gene expression profiles of key genes under two salinity conditions. Results of the current project can form the basis for further studies to confirm the functional roles of specific genes that influence salinity tolerance in the target species and more broadly in other freshwater teleost fishes. Ultimately, the approach can contribute to developing superior culture stocks of the target species.

The race to patent the SARS virus: The TRIPS agreement and access to essential medicines

This article considers the race to sequence the Severe Acute Respiratory Syndrome virus ('the SARS virus') in light of the debate over patent law and access to essential medicines. Part II evaluates the claims of public research institutions in Canada, the United States, and Hong Kong, and commercial companies, to patent rights in respect of the SARS virus. It highlights the dilemma of ’defensive patenting' - the tension between securing private patent rights and facilitating public disclosure of information and research. Part III considers the race to patent the SARS virus in light of wider policy debates over gene patents. It examines the application of such patent criteria as novelty, inventive step, utility, and secret use. It contends that there is a need to reform the patent system to accommodate the global nature of scientific inquiry, the unique nature of genetics, and the pace of technological change. Part IV examines the role played by the World Trade Organization and the World Health Organization in dealing with patent law and access to essential medicines. The article contends that there is a need to ensure that the patent system is sufficiently flexible and adaptable to accommodate international research efforts on infectious diseases.

Conserved gene structure and function of interleukin-10 in teleost fish

Interleukin-10 (IL-10) is an important immunoregulatory cytokine produced by various types of cells. Researchers describe here the isolation and characterization of olive flounder IL-10 (ofIL-10) cDNA and genomic organization. The ofIL-10 gene encodes a 187 amino acid protein and is composed of a five exon/four intron structure, similar to other known IL-10 genes. The ofIL-10 promoter sequence analysis shows a high level of homology in putative binding sites for transcription factors which are sufficient for transcriptional regulation ofIL-10. Important structural residues are maintained in the ofIL-10 protein including the four cysteines responsible for the two intra-chain disulfide bridges reported for human IL-10 and two extra cysteine residues that exist only in fish species. The phylogenetic analysis clustered ofIL-10 with other fish IL-10s and apart from mammalian IL-10 molecules. Quantitative real-time Polymerase Chain Reaction (PCR) analysis demonstrated ubiquitous ofIL-10 gene expression in the 13 tissues examined. Additionally, the induction of ofIL-10 gene expression was observed in the kidney tissue from olive flounder infected with bacteria (Edawardsiella tarda) or virus (Viral Hemorrhagic Septicemia Virus; VHSV). These data indicate that IL-10 is an important immune regulator that is conserved strictly genomic organization and function during the evolution of vertebrate immunity.

Antibody reactivity to the transmembrane protein of the caprine arthritis encephalitis virus correlates with severity of arthritis: No evidence for the involvement of epitope mimicry

Serum and synovial antibody reactivities of caprine arthritis encephalitis virus (CAEV) infected goats were assessed by Western blotting against purified CAEV antigen and the greatest intensity of reactivity in the serum of arthritic goats was to the gp45 transmembrane protein (TM). The extracytoplasmic domain of the TM gene was cloned into a pGEX vector and expressed in Escherichia coil as a glutathione S transferase fusion protein (GST-TM). This clone was found to be 90.5 and 89.2% homologous to published sequences of CAEV TM gene. Serum of 16 goats naturally infected with CAEV were examined by Western blotting for reactivity to the fusion protein. Antibody reactivity to the GST-TM correlated with clinically detectable arthritis (R = 0.642, P ≤ 0.007). The hypothesis that the immune response to the envelope proteins of the CAEV contributes to the severity of arthritis in goats naturally infected with CAEV via epitope mimicry was tested. Antibodies from 5 CAEV infected goats were affinity purified against the GST-TM fusion protein and tested for cross-reactivity with a series of goat synovial extracts and proteogylcans. No serum antibody response or cross-reactivity of affinity purified antibodies could be detected. Peptides of the CAEV SU that were predicted to be linear epitopes and a similar heat shock protein 83 (HSP) peptide identified by database searching, were synthesized and tested for reactivity in CAEV goats using ELISA, in vitro lymphocyte proliferation and delayed type hypersensitivity (DTH) assays. Peripheral blood lymphocytes from 10 of 17 goats with long term natural CAEV infections proliferated in vitro in response to CAEV and in vivo 3 of 7 CAEV infected goats had a DTH reaction to CAEV antigen. However, none of the peptides elicited significant cell mediated immune responses from CAEV infected goats. No antibody reactivity to the SU peptides or HSP peptide was found. We observed that the antibody reactivity to the CAEV TM protein associated with severity of arthritis however epitope mimicry by the envelope proteins of CAEV is unlikely to be involved.

Mimicry of 21. 5 KDa myelin basic protein peptide by a Maedi Visna virus polymerase peptide does not contribute to the pathogenesis of encephalitis in sheep

Epitope mimicry is the theory that an infectious agent such as a virus causes pathological effects via mimicry of host proteins and thus elicits a cross-reactive immune response to host tissues. Weise and Carnegie (1988) found a region of sequence similarity between the pol gene of the Maedi Visna virus (MVV), which induces demyelinating encephalitis in sheep, and myelin basic protein (MBP), which is known to induce experimental allergic encephalitis (EAE) in laboratory animals. In this study, cross-reactions between sera raised in sheep against synthetic peptides of MVV (TGKIPWILLPGR) and 21.5 kDa MBP (SGKVPWLKRPGR) were demonstrated using enzyme-linked immunosorbant assay (ELISA) and thin layer chromatography (TLC) immunoprobing. The antibody responses of MVV-infected sheep were investigated using ELISA against the peptides, and MBP protein, immunoprobing of the peptides on TPC plates and Western blotting against MBP. Slight significant reactions to the 21.5 kDa MBP peptide (P < 0.001) and to a lesser extent sheep MBP (P < 0.004) were detected in ELISA. The MBP peptide evoked stronger responses from more sera than the MVV peptide on immunoprobed TLC plates. On the Western blots, eight of the 23 sheep with Visna had serum reactivity to MBP. This slight reaction to MBP in MVV-infected sheep is of interest because of the immune responses to MBP evident in multiple sclerosis and EAE, but its relevance in Visna is limited since no correlation with disease severity was observed. The cell-mediated immune responses of MVV-infected sheep against similar peptides was assessed. The peptides did not stimulate proliferation of peripheral blood lymphocytes of MVV-infected sheep. Since the MVV peptide was not recognised by antibodies or T lymphocytes from MVV-infected and encephalic sheep, it was concluded that epitope mimicry of this 21.5 kDa MBP peptide by the similar MVV pol peptide was not contributing to the immunopathogenesis of Visna. The slight antibody response to MBP and the MBP peptide can be attributed to by-stander effects of the immunopathology of MVV-induced encephalitis.

Current trends in the etiology and diagnosis of HPV-related head and neck cancers

Human papilloma virus (HPV) infection is a major risk factor for a distinct subset of head and neck squamous cell carcinoma (HNSCC). The current review summarizes the epidemiology of HNSCC and the disease burden, the infectious cycle of HPV, the roles of viral oncoproteins, E6 and E7, and the downstream cellular events that lead to malignant transformation. Current techniques for the clinical diagnosis of HPV-associated HNSCC will also be discussed, that is, the detection of HPV DNA, RNA, and the HPV surrogate marker, p16 in tumor tissues, as well as HPV-specific antibodies in serum. Such methods do not allow for the early detection of HPV-associated HNSCC and most cases are at an advanced stage upon diagnosis. Novel noninvasive approaches using oral fluid, a clinically relevant biological fluid, allow for the detection of HPV and cellular alterations in infected cells, which may aid in the early detection and HPV-typing of HNSCC tumors. Noninvasive diagnostic methods will enable early detection and intervention, leading to a significant reduction in mortality and morbidity associated with HNSCC.

Role of enhanced vector transmission of a new West Nile virus strain in an outbreak of equine disease in Australia in 2011

Background In 2011, a variant of West Nile virus Kunjin strain (WNVKUN) caused an unprecedented epidemic of neurological disease in horses in southeast Australia, resulting in almost 1,000 cases and a 9% fatality rate. We investigated whether increased fitness of the virus in the primary vector, Culex annulirostris, and another potential vector, Culex australicus, contributed to the widespread nature of the outbreak. Methods Mosquitoes were exposed to infectious blood meals containing either the virus strain responsible for the outbreak, designated WNVKUN2011, or WNVKUN2009, a strain of low virulence that is typical of historical strains of this virus. WNVKUN infection in mosquito samples was detected using a fixed cell culture enzyme immunoassay and a WNVKUN- specific monoclonal antibody. Probit analysis was used to determine mosquito susceptibility to infection. Infection, dissemination and transmission rates for selected days post-exposure were compared using Fisher’s exact test. Virus titers in bodies and saliva expectorates were compared using t-tests. Results There were few significant differences between the two virus strains in the susceptibility of Cx. annulirostris to infection, the kinetics of virus replication and the ability of this mosquito species to transmit either strain. Both strains were transmitted by Cx. annulirostris for the first time on day 5 post-exposure. The highest transmission rates (proportion of mosquitoes with virus detected in saliva) observed were 68% for WNVKUN2011 on day 12 and 72% for WNVKUN2009 on day 14. On days 12 and 14 post-exposure, significantly more WNVKUN2011 than WNVKUN2009 was expectorated by infected mosquitoes. Infection, dissemination and transmission rates of the two strains were not significantly different in Culex australicus. However, transmission rates and the amount of virus expectorated were significantly lower in Cx. australicus than Cx. annulirostris. Conclusions The higher amount of WNVKUN2011 expectorated by infected mosquitoes may be an indication that this virus strain is transmitted more efficiently by Cx. annulirostris compared to other WNVKUN strains. Combined with other factors, such as a convergence of abundant mosquito and wading bird populations, and mammalian and avian feeding behaviour by Cx. annulirostris, this may have contributed to the scale of the 2011 equine epidemic.

The function of the RNA-binding protein TEL1 in moss reveals ancient regulatory mechanisms of shoot development

The shoot represents the basic body plan in land plants. It consists of a repeated structure composed of stems and leaves. Whereas vascular plants generate a shoot in their diploid phase, non-vascular plants such as mosses form a shoot (called the gametophore) in their haploid generation. The evolution of regulatory mechanisms or genetic networks used in the development of these two kinds of shoots is unclear. TERMINAL EAR1-like genes have been involved in diploid shoot development in vascular plants. Here, we show that disruption of PpTEL1 from the moss Physcomitrella patens, causes reduced protonema growth and gametophore initiation, as well as defects in gametophore development. Leafy shoots formed on ΔTEL1 mutants exhibit shorter stems with more leaves per shoot, suggesting an accelerated leaf initiation (shortened plastochron), a phenotype shared with the Poaceae vascular plants TE1 and PLA2/LHD2 mutants. Moreover, the positive correlation between plastochron length and leaf size observed in ΔTEL1 mutants suggests a conserved compensatory mechanism correlating leaf growth and leaf initiation rate that would minimize overall changes in plant biomass. The RNA-binding protein encoded by PpTEL1 contains two N-terminus RNA-recognition motifs, and a third C-terminus non-canonical RRM, specific to TEL proteins. Removal of the PpTEL1 C-terminus (including this third RRM) or only 16–18 amino acids within it seriously impairs PpTEL1 function, suggesting a critical role for this third RRM. These results show a conserved function of the RNA-binding PpTEL1 protein in the regulation of shoot development, from early ancestors to vascular plants, that depends on the third TEL-specific RRM.