Transformation zone sampling rate is a useful performance indicator for practitioners collecting cervical samples using SurePathTM liquid-based cytology system

An analysis of the reports of 53 982 liquid-based cytology (LBC) samples processed at the Royal Victoria Infirmary, Newcastle, reveals a significant relationship between the transformation zone (TZ) sampling rate observed in specimens submitted from different practices and their overall detection rate for dyskaryosis. The observed correlation (R = 0.184; P = 0.033, CI = 0.017 to 0.397) is very similar to that described previously using conventional cervical smears and confirms the potential relevance of TZ sampling rates as an indicator of consistently effective specimen collection. The correlation between unsatisfactory sample rates and detection rates for high-grade dyskaryosis (R = -0.188, P = 0.030, CI = -0.865 to -0.045) also shows a significant relationship for LBC samples which was not previously seen in conventional smears. The essential role of smear taker feedback, the use of transformation zone sampling and unsatisfactory smear rates as key indicators and the practical issues relating to routine reporting of transformation zone components are discussed.     

An Integrated Computational Infrastructure for a Virtual Tokyo Concepts and Examples

The evaluation of tradeoffs between technologies and policies for mitigation of environmental problems requires a systematic investigation of effects over the entire region under consideration. When attempting to model such large complex systems, issues such as usability, maintenance, and computing efficiency often become major modeling barriers. In this work a software prototype for integrating the services of computational models over the Internet, called DOME (distributed object-based modeling environment) is used to facilitate the construction of virtual Tokyo—a simulation platform for evaluating holistically the tradeoffs between various technologies for reducing the emissions of greenhouse gases. In making steps toward this ultimate goal, two models have been developed that use data defining spatial land-use distributions and the flows of goods expressed as an input-output table to provide information on the spatial and temporal characteristics of an urban region. Integrated, these models form a preliminary virtual Tokyo model when applied to Tokyo-specific databases. Given this platform, process models are applied to examine the effectiveness of using photovoltaic (PV) modules on the demand side to reduce conventional electric power generation and, thereby, also reduce carbon dioxide emissions. The results of introducing PV modules on the rooftops of buildings in Tokyo under various installation conditions are presented as a working example of the prototype. For full deployment on usable rooftop space, PV power generation could reduce carbon dioxide emissions from electric power generation by more than 12%. Future work will use the same methods as presented in this paper to examine cost, a critical determinant in the actual feasibility of PV module installation.     

Patterns of spread of Tomato spotted wilt virus in field crops of lettuce and pepper: spatial dynamics and validation of control measures

Patterns of spread of Tomato spotted wilt virus (TSWV) were examined in lettuce and pepper plantings into which thrips vectors spread the virus from external virus sources. These plantings were: 1) seven separate field trials into which TSWV ‘infector’ plants of tomato were introduced alongside or near to plantings of lettuce or pepper, and 2) three commercial lettuce plantings into which spread from nearby external infection sources was occurring naturally. The vector thrips species were Frankliniella occidentalis, F. schnitzel and Thrips tabaci, at least two of which were always present. Spatial data for plants with TSWV infection collected at different stages in the growing period were assessed by plotting gradients of infection, and using Spatial Analysis by Distance IndicEs (SADIE) and maps of spatial pattern. Despite the persistent nature of TSWV transmission by thrips vectors, in both lettuce and pepper plantings there was a steep decline in TSWV incidence with distance from external infection sources that were alongside them. The extent of clustering increased over time and was greatest closest to the source. The relationship between percentage infection and assessment date suggested that spread was predominantly monocyclic with only limited polycyclic spread. Development of isolated clusters of infected plants distant from TSWV sources within both crops was consistent with only limited polycyclic spread. Spread to lettuce was greater downwind than upwind of virus source, with magnitude and proximity of source determining the amount of spread. When 15 m wide fallow or non-host (cabbage) barriers separated TSWV sources from lettuce plantings, spread was slower and there was much less clustering with the latter. In commercial lettuce plantings, spread was favoured by TSWV movement within successive side-by-side plantings. The spatial data from the diverse scenarios examined enabled recommendations to be made over ‘safe’ planting distances between external infection sources of different magnitudes and susceptible crops that were short-lived (e.g. lettuce) or long-lived (e.g. pepper). They also helped validate the inclusion of isolation and ‘safe’ planting distances, planting upwind, prompt removal of virus sources, avoidance of side-by-side plantings, and deploying intervening non-host barrier crops as control measures within an integrated disease management strategy for TSWV in field vegetable crops.     

Phytoplankton chlorophyte structure as related to ENSO events in a saline lowland river (Salado River,Buenos Aires,Argentina)

We analyzed the phytoplankton present in the lower sector of the Salado River (Buenos Aires, Argentina) for 10 years (1995–2005) and detected significant changes occurring in chlorophyte abundance and species richness during La Niña event (1998–1999), which period was analyzed throughout the entire basin (main stream and tributaries). We compared the physicochemical and biologic variables between two El Niño–La Niña–Southern Oscillation (ENSO) periods – El Niño (March 1997–January 1998) and La Niña (May 1998–May 1999) – to identify possible indicators of a relationship between climatic anomalies and chlorophyte performance. Chlorophyte density increased during the La Niña. Under normal or extreme hydrologic conditions, mobile (Chlamydomonas spp.) and nonmobile (Monoraphidium spp.) chlorophytes codominated. These species belonged to Reynolds's functional groups X1 and X2, those typical of nutrient‐enriched environments. Comparative analyses between El Niño and La Niña periods indicated significant differences in physicochemical (K⁺, dissolved polyphenols, particulate reactive phosphorus, alkalinity, pH) and biologic (species diversity and richness, phytoplankton and chlorophyte total densities) variables between the two periods at all basin sites. During the La Niña condition, species richness was greater owing to interconnected shallow lakes and drainage‐channel inputs, while the Shannon diversity index was lower because of the high abundance values of Monoraphidium minutum. A detailed analysis of the chlorophytes in the entire basin, indicated that changes in density and species dominance occurred on a regional scale although diverse chlorophyte assemblages were identified in the different sectors of the Salado River basin. After La Niña event, the entire basin had the potential to revert to the previous density values, showing the resilience to global environmental changes and the ability to reestablish the general conditions of stability.     

Real‐time cell cycle imaging during melanoma growth,invasion, and drug response

Solid cancers are composed of heterogeneous zones containing proliferating and quiescent cells. Despite considerable insight into the molecular mechanisms underlying aberrant cell cycle progression, there is limited understanding of the relationship between the cell cycle on the one side, and melanoma cell motility, invasion, and drug sensitivity on the other side. Utilizing the fluorescent ubiquitination‐based cell cycle indicator (FUCCI) to longitudinally monitor proliferation and migration of melanoma cells in 3D culture and in vivo, we found that invading melanoma cells cycle actively, while G1‐arrested cells showed decreased invasion. Melanoma cells in a hypoxic environment or treated with mitogen‐activated protein kinase pathway inhibitors remained G1‐arrested for extended periods of time, with proliferation and invasion resuming after re‐exposure to a more favorable environment. We challenge the idea that the invasive and proliferative capacity of melanoma cells are mutually exclusive and further demonstrate that a reversibly G1‐arrested subpopulation survives in the presence of targeted therapies.     

Arthropod pests of currant and gooseberry crops in the U.K.: their biology,management and future prospects

• 1 Approximately 10–12 species of Ribes plants are cultivated for fruit production, mainly blackcurrants, red‐ and whitecurrants and gooseberries. These crops are increasingly recognized as rich sources of vitamin C and anthocyanins, with production rising by 24% in Europe subsequent to 1998. To date, research into insect pests of Ribes has been fragmented, with little appreciation of how changes in climate and agronomic practices affect biology.
• 2 We review 12 key pests of currant and gooseberry crops in Northern Europe, with specific emphasis on their biology and current management options. These are blackcurrant leaf curling midge Dasineura tetensi, blackcurrant sawfly Nematus olfaciens, common gooseberry sawfly Nematus ribesii, European permanent currant aphid Aphis schneideri, redcurrant blister aphid Cryptomyzus ribis, currant–sowthistle aphid Hyperomyzus lactucae, European gooseberry aphid Aphis grossulariae, woolly vine scale Pulvinaria vitis, common green capsid Lygocoris pabulinus, winter moth Operophtera brumata, clear wing moth Synanthedon tipuliformis and blackcurrant gall mite Cecidophyopsis ribis.
• 3 It is anticipated that global climate change could lead to increases in the incidence of some aphids through increased overwintering survival and longer seasonal activity. Moreover, changes in management practices such as increased cropping densities (from 5400 ha^?1 to 8700 ha^?1) and machine harvesting could lead to pest outbreaks through optimal microhabitats and increased susceptibility to pest colonization.
• 4 Future management options are considered, focusing on integrated pest management approaches, including behaviour‐manipulating semiochemicals, predictive models, biocontrol and improved plant resistance through breeding.

     

Quantification methods for Alexandrium catenella, a toxic dinoflagellate: Comparison of competitive enzyme-linked immunosorbent assay and sandwich hybridization integrated with a nuclease protection assay

Alexandrium catenella (Whedon et Kofoid) Balech, a toxic dinoflagellate, is a bloom-forming planktonic species in cold water coastal regions. It produces strong paralytic shellfish poisoning (PSP) toxins which are transmitted via tainted shellfish. These toxins can affect humans, other mammals, fish and birds. In this study, polyclonal antiserum against A. catenella was produced, and a competitive enzyme-linked immunosorbent assay (cELISA) was developed to detect A. catenella. The antiserum against A. catenella showed good specificity, the linear detection range was relatively large, between 38 and 600,000 cells. In addition, specific probes were designed to target the small subunit ribosomal RNA (SSU rRNA) of A. catenella, and quantitative sandwich hybridization integrated with a nuclease protection assay (NPA-SH) was established in order to identify and quantify A. catenella. The NPA-SH assay did not show good specificity as well as cELISA, by which A. catenella and A. tamarense could not be distinguished. Samples in different cell growth phases were analyzed with cELISA and NPA-SH. The results showed that the cell concentration calculated by cELISA was very similar with microscopy, while that of NPA-SH was sometimes higher than that of microscopy, especially in log phase. Comparing the two methods, both assays allow rapid identification of A. catenella without time-consuming microscopy when multiple sites need to be considered in routine monitoring. Meanwhile, cELISA was more specific and accurate in detection of A. catenella than NPA-SH.