Hepatitis C - a South African perspective

The existence of non-A, non-B (NANB) hepatitis was established in the 1970s, when accurate serological tests allowed exclusion of hepatitis A and B viruses as the cause of most cases of post-transfusion hepatitis. The term 'hepatitis C' was coined after molecular cloning of nucleic acid from highly infectious sera of chimpanzees identified an RNA virus as the primary cause of post-transfusion hepatitis (PTH). Sequence analysis and expression of the RNA has shown it to be closely related to the flavi- and pestiviruses. It has marked genomic variability which may affect its biological and immunological characteristics, is transmitted parenterally and sporadically, by as yet unidentified routes, and causes chronic indolent liver disease in 50 - 75% of infected patients. It is associated with hepatocellular carcinoma, glomerulonephritis, cryoglobulinaemia, auto-immune liver disease, lymphocytic sialadenitis and porphyria cutanea tarda. Up to 500 million people worldwide may be infected with hepatitis C virus (HCV), and many questions about the disease remain unanswered. Therapy is still largely ineffective and our current understanding of the long-term natural history, our methods of diagnosis, therapy, prevention and immunisation are suboptimal

Fumonisin-induced hepatocarcinogenesis: mechanisms related to cancer initiation and promotion.

We review the hepatocarcinogenic effects of fungal cultures of Fusarium verticillioides(= Fusarium moniliforme) strain MRC 826 in male BD IX rats. Subsequent chemical analyses of the fumonisin B (FB) mycotoxin content in the culture material used and long-term carcinogenesis studies with purified FB1 provide information about dose-response effects, relevance of hepatotoxicity during FB1-induced carcinogenesis, and the existence of a no-effect threshold. Fumonisin intake levels of between 0.08 and 0.16 mg FB/100 g body weight (bw)/day over approximately 2 years produce liver cancer in male BD IX rats. Exposure levels < 0.08 mg FB/100 g bw/day fail to induce cancer, although mild toxic and preneoplastic lesions are induced. The nutritional status of the diets used in the long-term experiments was marginally deficient in lipotropes and vitamins and could have played an important modulating role in fumonisin-induced hepatocarcinogenesis. Short-term studies in a cancer initiation/promotion model in rat liver provided important information about the possible mechanisms involved during the initial stages of cancer development by this apparently nongenotoxic mycotoxin. These studies supported the findings of long-term investigations indicating that a cytotoxic/proliferative response is required for cancer induction and that a no-effect threshold exists for cancer induction. The mechanisms proposed for cancer induction are highlighted and include the possible role of oxidative damage during initiation and the disruption of lipid metabolism, integrity of cellular membranes, and altered growth-regulatory responses as important events during promotion

Platforms to differentiate exotic pathovars of plant bacteria

Many of the EPPs that pose the biggest threat to the biosecurity of Australia’s plant industries are bacterial, but difficulties in identification to the subspecific or ‘ pathovar ’ level can seriously delay incursion management and affect market access. Pathovars are defined by host specificity so bio assays remain the definitive means of identification, but these require high level physical containment and can be slow and subjective , delaying diagnosis . Some pathovar - specific serological and molecular tests are available but better diagnostic methods are often required. This project used proteomics and metabolomics, platforms that identify functional molecules potentially associated with plant - pathogen interactions, to identify biomarkers that differentiate pathovars in species of Xanthomonas . Membrane - associated proteins from a collection of bacterial isolates were compared on 2Dimensional gels. Proteins that were found to be differentially expressed between distinct pathovars may be important modulators of host specificity so they were identified and the genes that encode them located by reference to genomic sequences . DNA - based assays targeting these genes were designed and validated for their specificity to the pathovar level . We have developed two new assays that provide levels of specificity not reported elsewhere in the literature. These assays specifically target the bacteria causing the different forms of citrus canker, but without cross - reaction to the closely - related organisms causing bacterial blight on cotton and Citrus Bacterial Spot. The molecular assays will be incorporated into the National Diagnostic Protocol for citrus canker through the SPHDS process. The metabolomics component has analysed metabolite expression in selected bacterial pathovars. Results showed separation between the different pathovars based on differential levels of expression of particular metabolites. These metabolites may be important determinants of pathogenicity. Neither proteomics nor metabolomics had been implemented before in the study of phytopathogenic bacteria and whilst both proved to be technically demanding, each delivered new biomarkers that differentiate phytopathogenic bacteria to a subspecific level . This confirmed the viability of these approaches as platforms to discover novel diagnostic targets. The new methods developed will be implemented into the national incursion response capability , improving the specificity of diagnostic testing available and reducing the possibility of false positive diagnosis . The project has fostered new collaborative partnerships both nationally (NSW, Victoria, WA) and internationally (to Thailand and the USA). The next phase of this work will provide a strong start - up project to the Plant Biosecurity Cooperative Research Centre ( PBCRC ) . This project has directly enhanced the plant bacteriology capacity of NSW and Australia trough the recruitment and training of science professionals and an undergraduate student , and supported the specialist training of a Thai scientist through allied project CRC20093

Merkel Cell Polyomavirus DNA in Respiratory Specimens from Children and Adults

Merkel cell polyomavirus (MCPyV) DNA was detected in 7 (1.3%) of 526 respiratory tract samples from patients in Australia with upper or lower respiratory tract symptoms. Partial T antigen and major capsid protein sequences of MCPyV identified in respiratory secretions showed high homology (99%–100%) to those found in Merkel cell carcinoma

Fulminant hepatitis B virus (HBV) infection in an infant following mother-to-child transmission of an e-minus HBV mutant: Time to relook at HBV prophylaxis in South African infants

The prevalence of hepatitis B virus (HBV) infection in pregnant women is high in South Africa (SA), yet prophylaxis to prevent mother-to-child transmission (MTCT) falls short of international recommendations. We describe a 10-week-old infant who developed fulminant hepatic failure following MTCT. The mother was hepatitis e-antibody positive and had a viral load of only 760 IU/mL. Genetic analysis of virus from mother and infant showed that both had the G1896A mutation in the preC/C gene, which truncates hepatitis e antigen (HBeAg) during translation, causing an HBeAg-negative phenotype. HBeAg attenuates antiviral immune responses, and its absence was probably responsible for the infant’s fulminant hepatitis, due to an uncontrolled immune attack on infected liver cells. Pregnant women are not tested for HBV infection in SA and MTCT rates are unknown. Addition of a birth dose of vaccine, HBV screening of pregnant women and antiviral prophylaxis to positive mothers should be prioritised

Grooming coercion and the post-conflict trading of social services in wild Barbary macaques

In animal and human societies, social services such as protection from predators are often exchanged between group members. The tactics that individuals display to obtain a service depend on its value and on differences between individuals in their capacity to aggressively obtain it. Here we analysed the exchange of valuable social services (i.e. grooming and relationship repair) in the aftermath of a conflict, in wild Barbary macaques (Macaca sylvanus). The relationship repair function of post-conflict affiliation (i.e. reconciliation) was apparent in the victim but not in the aggressor. Conversely, we found evidence for grooming coercion by the aggressor; when the victim failed to give grooming soon after a conflict they received renewed aggression from the aggressor. We argue that post-conflict affiliation between former opponents can be better described as a trading of social services rather than coercion alone, as both animals obtain some benefits (i.e. grooming for the aggressor and relationship repair for the victim). Our study is the first to test the importance of social coercion in the aftermath of a conflict. Differences in competitive abilities can affect the exchange of services and the occurrence of social coercion in animal societies. This may also help explain the variance between populations and species in their social behaviour and conflict management strategies

Evolution, appearance, and occupational success

Visual characteristics, including facial appearance, are thought to play an important role in a variety of judgments and decisions that have real occupational outcomes in many settings. Indeed, there is growing evidence suggesting that appearance influences hiring decisions and even election results. For example, attractive individuals are more likely to be hired, taller men earn more, and the facial appearance of candidates has been linked to real election outcomes. In this article, we review evidence linking physical appearance to occupational success and evaluate the hypothesis that appearance based biases are consistent with predictions based on evolutionary theories of coalition formation and leadership choice. We discuss why appearance based effects are so pervasive, addressing ideas about a "kernel of truth" in attributions and about coalitional psychology. We additionally highlight that appearance may be differently related to success at work according to the types of job or task involved. For example, leaders may be chosen because the characteristics they possess are seen as best suited to lead in particular situations. During a time of war, a dominant-appearing leader may inspire confidence and intimidate enemies while during peace-time, when negotiation and diplomacy are needed, interpersonal skills may outweigh the value of a dominant leader. In line with these ideas, masculine-faced leaders are favored in war-time scenarios while feminine-faced leaders are favored in peace-time scenarios. We suggest that such environment or task specific competencies may be prevalent during selection processes, whereby individuals whose appearance best matches perceived task competences are most likely selected, and propose the general term "task-congruent selection" to describe these effects. Overall, our review highlights how potentially adaptive biases could influence choices in the work place. With respect to certain biases, understanding their origin and current prevalence is important in order to potentially reduce discrimination in the work place

Female economic dependence and the morality of promiscuity

This article is made available through the Brunel Open Access Publishing Fund. Copyright @ The Author(s) 2014.In environments in which female economic dependence on a male mate is higher, male parental investment is more essential. In such environments, therefore, both sexes should value paternity certainty more and thus object more to promiscuity (because promiscuity undermines paternity certainty). We tested this theory of anti-promiscuity morality in two studies (N = 656 and N = 4,626) using U.S. samples. In both, we examined whether opposition to promiscuity was higher among people who perceived greater female economic dependence in their social network. In Study 2, we also tested whether economic indicators of female economic dependence (e.g., female income, welfare availability) predicted anti-promiscuity morality at the state level. Results from both studies supported the proposed theory. At the individual level, perceived female economic dependence explained significant variance in anti-promiscuity morality, even after controlling for variance explained by age, sex, religiosity, political conservatism, and the anti-promiscuity views of geographical neighbors. At the state level, median female income was strongly negatively related to anti-promiscuity morality and this relationship was fully mediated by perceived female economic dependence. These results were consistent with the view that anti-promiscuity beliefs may function to promote paternity certainty in circumstances where male parental investment is particularly important