The effects of exposure to seaweed on willingness to mate, oviposition, and longevity in seaweed flies

Abstract  1. Large male seaweed flies (Diptera: Coelopidae) are more likely to mate than smaller males. This is due to sexual conflict over mating, by which females physically resist male attempts to copulate. In some species, large males are simply more efficient at overpowering female resistance.
2. Female reluctance to mate is likely to have evolved due to the costs of mating to females. In many dipterans, males manipulate female behaviour through seminal proteins that have evolved through sperm competition. This behavioural manipulation can be costly to females, for example forcing females to oviposit in sub-optimal conditions and increasing their mortality.
3. Previous work has failed to identify any ubiquitous costs of mating to female coelopids. The work reported here was designed to investigate the effects of exposure to oviposition sites ( Fucus algae) on the reproductive behaviour of four species of coelopid. Algae deposition in nature is stochastic and females mate with multiple males in and around oviposition sites. Spermatogenesis is restricted to the pupal stage and there is last-male sperm precedence. It was predicted that males would avoid wasting sperm and would be more willing to mate, and to remain paired with females for longer, when exposed to oviposition material compared with control males. Females were predicted to incur longevity costs of mating if mating increased their rate of oviposition, especially in the presence of algae.
4. The behaviour of males of all four species concurred with the predictions; however mating did not affect female receptivity, oviposition behaviour, or longevity. Exposure to algae induced oviposition and increased female mortality in all species independently of mating and egg production. The evolutionary ecology of potential costs of mating to female coelopids are discussed in the light of these findings.     

Usefulness of using three different culture media for mold recovery in exposure assessment studies

The choice of culture media when performing exposure assessment for mold quantification is difficult since no standard methods exist and, in many cases, there is no way to predict, before hand, the mold population present and thus, select the most appropriate media. The aim of this project was to compare the efficiency and usefulness of 3 widely used culture media during the recovery of molds in sawmills. Andersen microbial samplers (AMS) and all-glass impingers-30 (AGI-30) were used to sample 51 work sites within 17 sawmills. Rose Bengal Agar (RBA), Czapek Solution Agar (CZA) and Sabouraud Dextrose Agar (SDA) were used directly in AMS and to plate AGI-liquid. The results show that there was no signification difference between the three culture media concerning the counts and the species recovery. However, SDA often lead to non usable counts. The variations obtained with the different culture media when AGI-30 were plated in triplicate was also not significantly different. However, only 19% of the species recovered at one site were present on all culture media. We believe the use of various media increases the chances of obtaining valid counts and an adequate species recovery.     

The Field of Art Production and Western Desert Acrylics1

Following the logic of Bourdieu's notion of ‘field’, acrylic art production in the Western Desert of Australia is positioned as a sub‐field in the field of Western art production. The significance of the cultural identity of the producer subordinates Western Desert acrylic art within the field and the shift in the criteria of legitimation constitutes it as a sub‐field. The capital at stake in the sub‐field of Western Desert acrylic art is differentiated and contingent upon legitimation of authenticity as defined by the Western field of art production. This capital is constituted through the positioning of Western Desert acrylics within the field of art production and is a manifestation of the struggle to maintain domination within the field.     

Effectiveness of appropriately trained nurses in preoperative assessment: randomised controlled equivalence/non-inferiority trial

ObjectiveTo determine whether preoperative assessments carried out by appropriately trained nurses are inferior in quality to those carried out by preregistration house officers.DesignRandomised controlled equivalence/non-inferiority trial.SettingFour NHS hospitals in three trusts. Three of the four were teaching hospitals.ParticipantsAll patients attending for assessment before general anaesthesia for general, vascular, urological, or breast surgery between April 1998 and March 1999.InterventionAssessment by one of three appropriately trained nurses or by one of several preregistration house officers.Results1907 patients were randomised, and 1874 completed the study; 926 were assessed by house officers and 948 by nurses. Overall 121/948 (13%) assessments carried out by nurses were judged to have possibly affected management compared with 138/926 (15%) of those performed by house officers. Nurses were judged to be non-inferior to house officers in assessment, although there was variation among them in terms of the quality of history taking. The house officers ordered considerably more unnecessary tests than the nurses (218/926 (24%) v 129/948 (14%).ConclusionsThere is no reason to inhibit the development of nurse led preoperative assessment provided that the nurses involved receive adequate training. However, house officers will continue to require experience in preoperative assessment.     

Stressful life experiences and risk of relapse of breast cancer: observational cohort study

ObjectiveTo confirm, using an observational cohort design, the relation between severely stressful life experiences and relapse of breast cancer found in a previous case-control study.DesignProspective follow up for five years of a cohort of women newly diagnosed as having breast cancer, collecting data on stressful life experiences, depression, and biological prognostic factors.SettingNHS breast clinic, London; 1991-9.ParticipantsA consecutive series of women aged under 60 newly diagnosed as having a primary operable breast tumour. 202/222 (91%) eligible women participated in the first life experiences interview. 170 (77%) provided complete interview data either up to 5 years after diagnosis or to recurrence.ResultsWe controlled for biological prognostic factors (lymph node infiltration and tumour histology), and found no increased risk of recurrence in women who had had one or more severely stressful life experiences in the year before diagnosis compared with women who did not (hazard ratio 1.01, 95% confidence interval 0.58 to 1.74, P=0.99). Women who had had one or more severely stressful life experiences in the 5 years after diagnosis had a lower risk of recurrence (0.52, 0.29 to 0.95, P=0.03) than those who did not.ConclusionThese data do not confirm an earlier finding from a case-control study that severely stressful life experiences increase the risk of recurrence of breast cancer. Differences in case control and prospective methods may explain the contradictory results. We took the prospective study as the more robust, and the results suggest that women with breast cancer need not fear that stressful experiences will precipitate the return of their disease.

What is already known on this topic

Women with apparently similar tumours at the time of presentation with breast cancer differ considerably in their disease-free survival and overall survivalSuch differences in outcome may well be explained by host and environmental factors, which could include psychological and social variablesData on the relation between severely stressful life experiences and cancer progression have been contradictory

What this study adds

Women who have a severely stressful life experience in the year before being diagnosed with breast cancer, or in the five years afterwards, do not seem to be at increased risk of developing a recurrence of the diseaseWomen with breast cancer need not fear that stressful experiences will precipitate the return of their disease.     

Potent, orally active inhibitors of lipoprotein-associated phospholipase A(2): 1-(biphenylmethylamidoalkyl)-pyrimidones.

A series of 1-(biphenylmethylamidoalkyl)-pyrimidones has been designed as nanomolar inhibitors of recombinant lipoprotein-associated phospholipase A(2) with high potency in whole human plasma. 5-(Pyrazolylmethyl) derivative 16 and 5-(methoxypyrimidinylmethyl) derivative 27 demonstrated excellent pharmacodynamic profiles which correlated well with their pharmacokinetic effects.     

Crystal structures of the active and alloxanthine-inhibited forms of xanthine dehydrogenase from Rhodobacter capsulatus.

Xanthine dehydrogenase (XDH), a complex molybdo/iron-sulfur/flavoprotein, catalyzes the oxidation of hypoxanthine to xanthine followed by oxidation of xanthine to uric acid with concomitant reduction of NAD+. The 2.7 A resolution structure of Rhodobacter capsulatus XDH reveals that the bacterial and bovine XDH have highly similar folds despite differences in subunit composition. The NAD+ binding pocket of the bacterial XDH resembles that of the dehydrogenase form of the bovine enzyme rather than that of the oxidase form, which reduces O(2) instead of NAD+. The drug allopurinol is used to treat XDH-catalyzed uric acid build-up occurring in gout or during cancer chemotherapy. As a hypoxanthine analog, it is oxidized to alloxanthine, which cannot be further oxidized but acts as a tight binding inhibitor of XDH. The 3.0 A resolution structure of the XDH-alloxanthine complex shows direct coordination of alloxanthine to the molybdenum via a nitrogen atom. These results provide a starting point for the rational design of new XDH inhibitors.     

The importance of combining air sampling and surface analysis when studying problematic houses for mold biodiversity determination

Houses that underwent water damages are often responsible for heath problems of the occupants. Since there is no universally used protocol for the analysis, we wanted to verify the usefulness of surface sampling versus air sampling for the evaluation of mold diversity in problematic houses and the value of the number of visible mold growth zones to predict air quality. Seventeen houses were sampled for culturable molds in the air and on the surfaces showing contamination. We compared the mold taxa found in the air and on the surfaces and verified the correlation between the number of moldy surfaces and airbone mold concentration. This study demonstrated that, surprisingly, some of the so called wet spore molds (e.g. Stachybotrys) were found more often from air than surface samples whereas, some dry spore molds (e.g. Asp. fumigatus) was more easily isolated from surface samples. There was a good correlation between the number of visible mold growth zones and the concentration of airborne molds. We conclude that air and surface sampling are necessary to evaluate mold diversity in problematic houses and that the number of mold growth zones is a good predictor of airborne mold concentration.     

Immortalisation of Primary Cells

Knowledge of the target cells is fundamental to maximise efficiency in attempts at immortalisation of specific cell types. It is also important to optimise the primary cell culture system to promote the survival of the target cell population. Other important factors that may influence the success in obtaining immortalised cells include the toxicity and efficiency of the immortalisation procedure. These can be assessed experimentally and if necessary appropriate techniques can be employed to purify the target cells. When cell lines have been established it is vital to assess them at an early stage for desired scientific and practical features as well as determining their stability and life-span. Furthermore, early characterisation of cell line authenticity (e.g. genetic characters, species of origin) and quality control testing will avoid wasted time and resources should contamination with micro-organisms or another cell line occur. Establishing a programme of immortalisation is a serious undertaking that should only be considered when there are no candidate continuous cell lines available. However, new approaches to modify the biology of cells to give extended life-span, whilst retaining the characteristics of differentiated cells in vivo, will hopefully provide valuable new substrates for in vitro toxicology.