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Anthracnose fruit rot of blueberries caused by Colletotrichum acutatum is a serious problem in humid blueberry-growing regions of North America. In order to develop a disease prediction model, environmental factors that affect mycelial growth, conidial germination, appressorium formation and fruit infection by C. acutatum were investigated. Variables included temperature, wetness duration, wetness interruption and relative humidity. The optimal temperature for mycelial growth was 26°C, and little or no growth was observed at 5 and 35°C. The development of melanized appressoria was studied on Parafilm-covered glass slides and infection was evaluated in immature and mature blueberry fruits. In all three assays, the optimal temperature for infection was identified as 25°C, and infections increased up to a wetness duration of 48 h. Three-dimensional Gaussian equations were used to assess the effect of temperature and wetness duration on the development of melanized appressoria ( R2 = 0·89) on Parafilm-covered glass slides and on infection incidence in immature ( R2 = 0·86) and mature ( R2 = 0·90) blueberry fruits. Interrupted wetness periods of different durations were investigated and models were fitted to the response of melanized appressoria ( R2 = 0·95) and infection incidence in immature ( R2 = 0·90) and mature ( R2 = 0·78) blueberry fruits. Additionally, the development of melanized appressoria and fruit infection incidence were modelled in relation to relative humidity ( R2 = 0·99 and 0·97, respectively). Three comprehensive equations were then developed that incorporate the aforementioned variables. The results lay the groundwork for a disease prediction model for anthracnose fruit rot in blueberries. [ABSTRACT FROM AUTHOR]

Transcriptional activity of the Junonia coenia densovirus ( JcDNV) P9 promoter depends on a 557-bp sequence located within the overlapping 3′ sequences for viral capsid and nonstructural genes. Utilizing a somatic transformation assay to assess JcDNV promoter activity in Drosophila melanogaster and Plodia interpunctella, viral sequences were subjected to deletional analysis. Removal of a 685-bp fragment reduced P9-driven expression to background levels. Inclusion of a second expression cassette demonstrated vector persistence and confirmed somatic transformation. P9 promoter-driven expression was restored by insertion of a 557-bp JcDNV fragment or by inclusion of a heterologous baculovirus hr5 enhancer. Consensus polycomb transcriptional factor binding sites were identified within the 557-bp fragment, which suggests a potential role in regulating densoviral transcription. [ABSTRACT FROM AUTHOR]

A somatic transformation gene vector that exploits the genomic integration properties of Junonia coenia lepidopteran densovirus ( JcDNV) sequences in vivo has been developed. JcDNV somatic transformation vectors are derivatives of plasmids containing an interrupted genome of JcDNV that provide efficient, robust vectors that can be used to examine regulation of chromosomally integrated transgenes in insects. Microinjection of JcDNV plasmids into syncytial embryos of Drosophila melanogaster or the lepidopterans Plodia interpunctella, Ephestia kuehniella or Trichoplusia ni resulted in persistent transgene expression throughout development. Inclusion of transgenes with tissue-specific promoters resulted in expression patterns canonical with phenotypes of piggyBac germline transformants. Somatic transformation required the presence of the viral inverted terminal repeat in cis only and did not depend upon non-structural viral proteins. [ABSTRACT FROM AUTHOR]

This paper seeks to understand better the media practices of people who are directly affected by an illness or health problem. Internet sites that have been created by people with HIV/AIDS are examined as a strategy for self-representation. This analysis identifies four prominent 'organising themes' in Internet sites: autobiography; expertise; self promotion; and dissent. It is argued that there is a connection between media activism within the contemporary AIDS movement and Internet use among people with HIV/AIDS. This paper discusses the potential of the Internet, as a form of media activism, to raise the private troubles of people with health problems as public issues through a revitalisation of the public sphere in contemporary post-industrial societies. [ABSTRACT FROM AUTHOR]

Objective: We monitored the recovery of immune responses to recall antigens in 35 HIV-infected patients receiving combination antiretroviral therapy (HAART). Methods: Patients infected with HIV either through drug injection (IDU) or by homosexual intercourse (HX), attending two Edinburgh clinics were studied. All had been on HAART for periods of between 6 months and 2 years and were receiving one or two nucleoside reverse transcriptase inhibitors plus combinations of protease inhibitors and/or non-nucleoside reverse transcriptase inhibitors. Sequential samples from each patient, stored in liquid nitrogen, were thawed and set up in proliferation assays with the following antigens: (i) environmental antigens: streptokinasestreptodornase (SK-SD); Candida albicans whole antigen (CA) and PPD from Mycobacterium avium complex (PPD-MAC) and (ii) antigens from opportunistic organisms: PPD from M. tuberculosis (PPD-TB) and tetanus toxoid C-fragment (TTC). Results: Partial recovery of lymphoproliferative responsiveness to environmental antigens was observed, in particular to Candida albicans, but negligible recovery of responsiveness to antigens from opportunistic organisms. Conclusions: Patients who respond to antiretroviral therapy recover their ability to respond to environmental organisms. Those with advanced disease at the start of antiretroviral therapy may have lost their immunological memory for opportunistic pathogens irretrievably. [ABSTRACT FROM AUTHOR]