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Notes: The changes in weed:crop competition as affected by the interaction of slurry distribution pattern with crop sowing pattern was examined, using the parameters dry matter (DM) production, nitrogen (N) uptake and recovery of applied N in spring wheat and weeds. Pig slurry enriched with isotopic nitrogen (15N) was applied either fully incorporated or in concentrated bands. The two slurry distribution patterns were combined with either crop density or distance between the slurry band and seed row. Spring wheat and weeds were sampled separately seven times during the season. A high and fast crop recovery of applied N coincident with a low recovery in weeds may be obtained by at least three management elements: sowing the crop with a high seed density, sowing the crop row close to the band-applied slurry N, and early sowing. The effects on crop DM, N-uptake and 15N recovery of a high crop density and a narrow distance between the slurry band and crop row appear clearly at the beginning of the spring wheat elongation phase. For weeds the effects were most pronounced for 15N recovery, and using DM as the only response variable may cause insignificant results. However, methods for N application may be part of a strategy controlling weeds, but to obtain satisfactory weed control the N management needs to be supplemented with chemical or mechanical weed management.

Notes: Reductions in testosterone and luteinizing hormone levels and reduced sexual functions have been reported in Huntington's disease (HD) patients. Atrophy of the reproductive organs and loss of fertility have also been observed in the R6/2 mouse, which is currently the most studied transgenic model of HD. In an effort to define the cause of infertility we studied the expression of gonadotropin-releasing hormone (GnRH) in the medial septum, diagonal band of Broca and hypothalamus of R6/2 male mice during sexual maturation. We found a progressive reduction in the numbers of GnRH-immunoreactive neurons in the analysed brain areas of R6/2 mice starting at 5 weeks of age and becoming statistically significant with only 10% of the neurons remaining by 9 weeks of age. Atrophy of testes and seminal vesicles combined with a significant reduction in serum and testicular testosterone levels were detected in 12-week-old R6/2mice. These results suggest that infertility in the R6/2 males is due either to death of GnRH neurons or to a reduction in GnRH expression leading to a downstream impairment of the gonadotropic hormones. Gonadotropic hormone replacement did not mitigate weight loss or restore motor function in R6/2 males.

Notes: Two egg batches of spotted wolffish, Anarhichas minor Olafsen, were incubated at 4, 6 and 8°C. Embryo samples were fixed and compared on each 100th daydegree until hatching (up to 1000 daydegrees). Embryos, yolk sacs and chorions were dissected and the sizes, wet and dry weights were recorded separately. Comparisons of gross morphologies and measured parameters showed increasing and generally significant differences with time between the incubation temperatures. Lower temperatures produced longer and more differentiated larvae at hatch with a smaller yolk sac. Even though some unexpected deviations were registered among batches and experimental groups, it was clear that temperature affected embryo survival and time of hatching. Overall survival was best at 6°C, in agreement with results from earlier studies. Yolk conversion efficiencies measured around the hatching point were generally high, ranging from 60% to 78%, varied between the two batches and probably reflected the developmental variations between embryos and larvae at the respective ages (daydegrees). The hatching process was apparently an energy-demanding period; yolk conversion efficiencies of unhatched embryos of similar age at each temperature were always higher. Temperature is one environmental factor that can be manipulated in hatcheries to induce hatching of viable larvae at an optimal stage of differentiation with respect to first-feeding success and early survival.

Notes: More than 100 years ago Wilhelm Roux (1895) introduced the term “functional adaptation to anatomy and physiology”. Compared with other organ systems the functional adaptation processes are best identifiable in the locomotor system, like for example in the two types of tendons: traction and gliding tendons. Traction tendons are tendons where the direction of pull is in line with the direction of the muscle (e.g. Achilles tendon). Gliding tendons (e.g. tibialis posterior tendon) change direction by turning around a bony or fibrous hypomochlion. In this region the tendon is subjected to intermittent compressive and shear forces and the extracellular matrix consists of avascular fibrocartilage. Avascularity is considered to be a key factor for the etiology of degenerative tendon disease. The repair capability after repetitive microtrauma is strongly compromised in avascular tissue of gliding tendons. Reduced vascularity is not a specific feature of gliding tendons; several studies have shown that the number and size of blood vessels are largely shortened in the waist of the Achilles tendon. However, histological biopsies from degenerated Achilles tendons and Doppler flow examinations revealed a high blood vessel density in patients with degenerative tendon disease.Angiogenesis is mediated by angiogenic factors and recent studies have shown that the vascular endothelial growth factor (VEGF) is highly expressed in degenerative Achilles tendons, whereas VEGF expression is nearly completely downregulated in healthy tendons. Several factors are able to upregulate VEGF expression in tenocytes: hypoxia, inflammatory cytokines and mechanical load. Since VEGF has the potential to stimulate the expression of matrix metalloproteinases and inhibit the expression of tissue inhibitors of matrix metalloproteinases tissue inhibitor of metalloproteinases (TIMP) in various cell types (e.g. endothelial cells, fibroblasts, chondrocytes), this cytokine might play a significant role for the pathogenetic processes during degenerative tendon disease. An animal experiment in the rabbit has shown that local injection of VEGF reduced the material properties of the Achilles tendon. These experimental findings are in accordance with clinical results that a locally administered (in the area with neovascularization) sclerosing drug (Polidocanol) has a beneficial effect on chronic mid-portion Achilles tendinosis.In conclusion, decreased and increased vascularity might be involved in the pathogenesis of degenerative Achilles tendon disease.

Notes: Objective  To determine the accuracy of polymerase chain reaction (PCR) analysis of amniotic fluid for fetal toxoplasmosis according to clinical predictors of outcome and study centre.Design  Prospective cohort study.Setting  Nine European centres.Population  Women with suspected toxoplasma infection identified by prenatal screening.Methods  Logistic regression was used to examine the effects of gestational age at maternal seroconversion, treatment and timing of amniocentesis, on PCR accuracy, and to calculate the post-test probability of congenital toxoplasmosis.Main outcome measures  Infants had congenital toxoplasmosis if specific IgG persisted beyond 11.5 months. Uninfected infants had undetectable IgG in the absence of anti-toxoplasma treatment.Results  Of 593 PCR results, 64 were positive (57 confirmed infected), and 529 were negative (23 confirmed infected). The likelihood ratio for a positive PCR result decreased significantly with trimester at seroconversion, but did not change significantly for a negative result. Weak associations were detected between sensitivity and, inversely, with specificity, and gestational age at maternal seroconversion. There was no significant association between sensitivity and centre, type or duration of treatment, or timing of amniocentesis. Specificity differed significantly between centres (P 〈 0.001). The change in pre- to post-test probability of infection was maximal for a positive PCR after first trimester seroconversion, affecting 1% of women tested, and a negative PCR after third trimester seroconversion, affecting half the women tested.Conclusions  Prediction of the risk of congenital toxoplasmosis should combine estimates of test accuracy and maternal–fetal transmission, which take account of the gestational age at which the mother seroconverted. Local laboratory standards will affect the generalisability of these results.

Notes: Objective: As atrial conduction slowing is important in the pathogenesis of atrial reentry arrhythmias, a drug that increases atrial conduction or prevents atrial conduction slowing could serve to prevent atrial reentry arrhythmias. In this study, we investigated whether the novel stable antiarrhythmic peptide analog, ZP123, was able to prevent atrial conduction slowing. Methods: We examined the effect of ZP123 on metabolic stress-induced changes in conduction velocity (CV) and on dynamic CV restitution in isolated left atria from male Sprague-Dawley rats. We performed binding of ZP123 to a broad panel of 80 different cardiac and noncardiac ion channels and receptors and examined the effect of ZP123 on HERG channel conductance. Results: ZP123 dose-dependently prevented metabolic stress-induced atrial CV slowing at doses ranging from 1 nM to 10 μM. ZP123 did not affect CV during physiological conditions nor did it affect dynamic CV restitution. ZP123 had no effect on atrial contractility. ZP123 showed no or low affinity binding to all ion channels and receptors examined. ZP123 had no effects on HERG channel activity in concentrations that affected atrial conduction. The concentration of ZP123 giving maximal effect on atrial conduction (100 nM) inhibited the outward K+-current by 2.7 ± 0.1%. Conclusion: ZP123 has no effects on atrial conduction during physiological conditions, but it selectively prevents atrial conduction slowing during metabolic stress.

Notes: Aim  To assess the level to which parents from deprived and socially dysfunctional families collaborate in complex and time-consuming research.Design  Home-based study, of early physiological development in infants from a severely deprived area. Overnight continuous recordings of deep-body temperature with twice daily urine collection, parental daily diary of life-events and completion of child care social and psychological assessment by interview questionnaire. Measurements taken between age 6–12 weeks, each lasted 8–12 h per night, averaging four nights per baby. Level of parental participation assessed in relation to ongoing lifestyle pressures.Setting  Home based. Inner city deprived estate.Participants  Random sample of mothers with newborn healthy infants.Measurements  A total of 87 overnight deep body temperature recordings were made on 22 infants each lasting 8–12 h; 174 urine samples were taken; and 22 sets of questionnaires were completed.Results  Of 62 inner city deprived parents, 39 (62%) agreed to participate. 22 (35%) completed the study. Ongoing lifestyle pressures were high including incidents of burglary, fire and family violence. Family and partner pressures and life crises overwhelmed 10 non-participations.Conclusions  Research partnerships can be developed with underprivileged families facing severe life-events. Parents were highly motivated to complete what they perceived as important infant care research.

Notes: The Escherichia coli ompA mRNA, encoding a highly abundant outer membrane protein, has served as a model for regulated mRNA decay in bacteria. The half-life of this transcript correlates inversely with the bacterial growth rate and is growth stage-dependent. The stability of the messenger is determined by the 5′-untranslated region which possesses cleavage sites for RNase E. Hfq binds to this region, is essential for controlling the stability and has been suggested to directly regulate ompA mRNA decay. Here we report that the 78 nucleotide SraD RNA, which is highly conserved among Enterobacteriaceae, acts in destabilizing the ompA transcript when rapidly grown cells enter the stationary phase of growth. During this growth-stage the expression of SraD RNA becomes strongly increased. The SraD-mediated decay of ompA mRNA depends on Hfq and in vitro studies revealed that Hfq facilitates binding of the regulatory RNA to the translational initiation region of the messenger. Deletion of sraD, however, does not significantly affect the stability of the ompA mRNA in slowly growing cells. Our results indicate that distinct regulatory circuits are responsible for growth phase- and growth rate-dependent control of the ompA mRNA stability.

Notes: The reproductive biology of three species in the genus Artedius(A. harringtoni, A. lateralis and A. fenestralis) was studied, including parental behaviour, mate choice, fertilization mode, gamete morphology and behaviour, and gonad morphology to help understand the coevolution of reproductive characteristics with potentially different modes of fertilization. In all three species, males guard multiple clutches at oviposition sites. In laboratory mate-choice experiments, males appearred to prefer to defend sites containing eggs and were better able to attract mates at these sites. There was evidence that internal gomete association, although more pronounced in A. harringtoni, existed in all three species. Sperm behaviour and morphology and histological analysis of gonads suggested that A. fenestralis and A. lateralis were more likely to engage in typical external fertilization. The adoption of eggs and their effect on female mate-choice patterns appearred to reduce the importance of certainty of paternity in these species, and probably increased the evolutionary stability of male parental care.

Notes: We examined the effects of subtle and blatant prejudice and the enforcement of workforce homogeneity on employment discrimination in an experimental simulation. German participants who were advised to maintain a homogeneous (i.e., German) workforce, as hypothesized, selected fewer foreign applicants for a job interview than did participants who did not receive this advice. An interaction qualified this main effect, such that subtly prejudiced participants reacted to the advice to maintain a homogeneous workforce, but blatantly prejudiced and nonprejudiced individuals did not. The implications of these findings for research and practice are discussed.