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This article reports the first occurrence of Ornithogalum virus 3 (OV3) in Galtonia candicans plants in the United Kingdom. The virus was detected in a leaf sample from a plant nursery in south-east England. The sample tested negative for cucumber mosaic virus and positive for potyvirus. Further analysis revealed that the virus had the highest sequence identity with an isolate of OV3. OV3 negatively affects the appearance of the flowers and plant, impacting its viability for commercial cultivation. The virus has been previously reported in other countries, and there is a need for increased surveillance to understand its distribution and host range. [Extracted from the article]

This paper presents the mechanical and hydraulic behaviour of passively prestressed concrete-lined pressure tunnels embedded in elastic transversely isotropic rocks subjected to non-uniform in situ stresses. Two cases are distinguished based on whether the in situ vertical stress in the rock mass is higher, or lower than the in situ horizontal stress. A two-dimensional finite element model was used to study the influence of dip angle, α, and horizontal-to-vertical stress ratio, k, on the bearing capacity of prestressed concrete-lined pressure tunnels. The study reveals that the in situ stress ratio and the orientation of stratifications in the rock mass significantly affect the load sharing between the rock mass and the lining. The distribution of stresses and deformations as a result of tunnel construction processes exhibits a symmetrical pattern for tunnels embedded in a rock mass with either horizontal or vertical stratification planes, whereas it demonstrates an unsymmetrical pattern for tunnels embedded in a rock mass with inclined stratification planes. The results obtained for a specific value α with coefficient k are identical to that for α + 90° with coefficient 1/ k by rotating the tunnel axis by 90°. The maximum internal water pressure was determined by offsetting the prestress-induced hoop strains at the final lining intrados against the seepage-induced hoop strains. As well as assessing the internal water pressure, this approach is capable of identifying potential locations where longitudinal cracks may occur in the final lining. [ABSTRACT FROM AUTHOR]

Background/Objectives:Maternal obesity increases the risk of poor pregnancy outcome including stillbirth, pre-eclampsia, fetal growth restriction and fetal overgrowth. These pregnancy complications are associated with dysfunctional syncytiotrophoblast, the transporting epithelium of the human placenta. Taurine, a β-amino acid with antioxidant and cytoprotective properties, has a role in syncytiotrophoblast development and function and is required for fetal growth and organ development. Taurine is conditionally essential in pregnancy and fetal tissues depend on uptake of taurine from maternal blood. We tested the hypothesis that taurine uptake into placental syncytiotrophoblast by the taurine transporter protein (TauT) is lower in obese women (body mass index (BMI)⩾30 kg m−2) than in women of ideal weight (BMI 18.5-24.9 kg m−2) and explored potential regulatory factors.Subjects/Methods:Placentas were collected from term (37-42-week gestation), uncomplicated, singleton pregnancies from women with BMI 19-49 kg m−2. TauT activity was measured as the Na+-dependent uptake of 3H-taurine into placental villous fragments. TauT expression in membrane-enriched placental samples was investigated by western blot. In vitro studies using placental villous explants examined whether leptin or IL-6, adipokines/cytokines that are elevated in maternal obesity, regulates TauT activity.Results:Placental TauT activity was significantly lower in obese women (BMI⩾30) than women of ideal weight (P<0.03) and inversely related to maternal BMI (19-49 kg m−2; P<0.05; n=61). There was no difference in TauT expression between placentas of ideal weight and obese class III (BMI⩾40) subjects. Long-term exposure (48 h) of placental villous explants to leptin or IL-6 did not affect TauT activity.Conclusions:Placental TauT activity at term is negatively related to maternal BMI. We propose that the reduction in placental TauT activity in maternal obesity could lower syncytiotrophoblast taurine concentration, compromise placental development and function, and reduce the driving force for taurine efflux to the fetus, thereby increasing the risk of poor pregnancy outcome. [ABSTRACT FROM AUTHOR]

Morphogens act in developing tissues to control the spatial arrangement of cellular differentiation. The activity of a morphogen has generally been viewed as a concentration-dependent response to a diffusible signal, but the duration of morphogen signalling can also affect cellular responses. One such example is the morphogen sonic hedgehog (SHH). In the vertebrate central nervous system and limbs, the pattern of cellular differentiation is controlled by both the amount and the time of SHH exposure. How these two parameters are interpreted at a cellular level has been unclear. Here we provide evidence that changing the concentration or duration of SHH has an equivalent effect on intracellular signalling. Chick neural cells convert different concentrations of SHH into time-limited periods of signal transduction, such that signal duration is proportional to SHH concentration. This depends on the gradual desensitization of cells to ongoing SHH exposure, mediated by the SHH-dependent upregulation of patched 1 (PTC1), a ligand-binding inhibitor of SHH signalling. Thus, in addition to its role in shaping the SHH gradient, PTC1 participates cell autonomously in gradient sensing. Together, the data reveal a novel strategy for morphogen interpretation, in which the temporal adaptation of cells to a morphogen integrates the concentration and duration of a signal to control differential gene expression. [ABSTRACT FROM AUTHOR]

The first part of the paper describes a portable and flexible data assimilation environment (DATools) for easy application of data assimilation and calibration techniques to models that are used in smaller-scale engineering applications, for example to guide temporary offshore construction works, marine surveying and salvage operations. These applications are characterized by the need for detailed forecasts of often strongly non-linear marine behaviour in shallow-shelf seas under constraints of limited field measurements and absence of large-scale computing facilities. The applications are often prepared, and their results are interpreted by end-user engineers in field offices, not well acquainted with the data assimilation theory. The DATools data assimilation environment has been designed to facilitate such applications. It presently features an ensemble Kalman filter and two particle filters. These can be coupled to any process model in a standardized way through the so-called Published Interface that is used in an increasing number of flood-forecasting applications across Europe. The design of the system and its main modules are discussed, looking at the system from a non-specialist user perspective and focusing on modularity, transparency, user guidance, intuitive and flexible uncertainty prescription. The second part of the paper describes a typical example application of data assimilation in an engineering environment for which the modelling environment has been developed: the daily forecast of current and salinity profiles to guide construction works in Osaka Bay. An ensemble Kalman filter-based steady-state Kalman filter is developed for assimilation of salinity and horizontal currents into an existing three-dimensional flow model for the highly non-linear stratified shallow bay. Calibration results are summarised for both hindcast mode and forecast mode. After assessment of the results, a second, improved model setup is described, including now assimilation of temperature and water level as well as currents and salinity. The calibration results are shown to improve further. Both applications show that significant forecast improvements can be possible with data assimilation in typical engineering applications, notwithstanding operational constraints such as limited measurement data and restricted computational infrastructure. It is argued that the described portable data assimilation environment is well suited for temporary engineering applications as it provides typical end-user functionalities for data assimilation and will so allow the user to focus on the characteristics of the physical processes and interpretation of the results instead of on details of the mathematical techniques. This should make practical data assimilation accessible for a much wider (end) user community in oceanography and offshore. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare Na+/H+ exchanger (NHE) activity in the microvillous (MVM) and basal (BM) plasma membrane of the human placental syncytiotrophoblast and to determine the relative contribution of various NHE isoforms to this activity. Uptake of22Na into isolated MVM vesicles in the presence of a H+ gradient, at initial rate, was four- to fivefold higher than that by BM vesicles (214±28 vs. 49±9 pmol/mg protein per 30 s, respectively, means±SEM,n=8, 6,P<0.001). The22Na uptake by MVM, but not by BM, was reduced in the absence of a H+ gradient and in the presence of 500 µM amiloride. To determine the contribution of NHE1, NHE2 and NHE3 isoforms to NHE activity in MVM, we investigated the effect of amiloride analogues which show isoform selectivity. HOE 694, an analogue selective for NHE1 at low concentrations, inhibited22Na uptake with an EC50 of 0.13±0.05 µM (n=6), whereas S3226, an analogue selective for NHE3 at low concentrations had an EC50 of 3.01±0.85 µM (n=5). To investigate this further, we measured recovery of syncytiotrophoblast intracellular pH (pHi) from an acid load using a H+-selective, fluorescent dye (BCECF) loaded into isolated intact placental fragments. This recovery was blocked in the absence of Na+ and the presence of amiloride (500 µM) and concentrations of HOE 694 and S3226 were comparable to those used in vesicle experiments. Overall these data show that under the conditions used NHE activity in the term placental syncytiotrophoblast is absent from BM. NHE activity in the MVM is attributable predominantly to NHE1. [ABSTRACT FROM AUTHOR]

Patients with meningococcal disease have increased plasma levels of proinflammatory cytokines IL-6, IL-1ß, and TNF-a, with higher levels associated with fatal outcome. This study investigated whether polymorphisms in genes encoding these cytokines, and in those encoding anti-inflammatory IL-10 and IL-1Ra, are associated with the outcome in patients with meningococcal disease. Seven polymorphisms were genotyped in 183 meningococcal disease patients and 389 controls. The IL-6 -174 G/G and IL-10 -1082 A/A genotypes were more frequent in nonsurvivors compared with survivors (P=0.023 IL-6, 0.25 IL-10), and in patients with severe disease compared to those with mild disease (P=0.037 IL-6, 0.0078 IL-10). An association was also found between meningococcal disease and the IL-1RN VNTR polymorphism, but no association was observed with the LTA +252, TNF -308, IL-10 -592, or IL-1B +3953 polymorphisms. We conclude that genetic variability in the IL-6, IL-10, and IL-1RN genes is associated with a poor outcome in meningococcal disease.Genes and Immunity (2003) 4, 533-540. doi:10.1038/sj.gene.6364020 [ABSTRACT FROM AUTHOR]

Anticipation has attracted much interest and has been demonstrated in several neuropsychiatric disorders. For some disorders, this phenomenon has been found to correlate with the repeat number in large and unstable repeats (CAG/CTG). In addition, case control studies have suggested an increase in triplet repeat size in the psychoses. Recently, it was reported that the larger alleles (longer than 19 repeats) of the second potassium channel gene hSKCa3 are associated with schizophrenia in European and American samples. A similar trend, though not statistically significant, was also seen in bipolar disorder samples. This was further supported by an independent UK study. In this investigation, we have examined Irish familial schizophrenic patients, bipolar affective disorder patients and ethnically matched controls in an effort to replicate these findings. No significant differences between the patients and the control groups were observed. In addition, linkage analyses in the multiplex schizophrenic families showed no evidence for linkage or linkage disequilibrium. We concluded that the polymorphism of the second CAG repeat of the hSKCa3 gene is not a risk factor in schizophrenia or bipolar disorder, at least in the Irish population. [ABSTRACT FROM AUTHOR]

The genetic variation which underlies the thermolability and low enzyme activity of 5,10-methylenetetrahydrofolate reductase (MTHFR; C677T) has been extensively studied in many populations, including the Irish population. To describe the examination of the C677T substitution in two new control samples drawn from the Irish population. A collection of 487 serum samples was obtained through the blood transfusion services of both the Republic of Ireland and Northern Ireland and a further 115 samples from volunteers. In both samples, the frequency of the thermolabile/low enzyme activity allele (T) was higher than that previously reported for the Irish population. This finding thus supports the need for a greater use of internal control/family-based association studies, as opposed to the classic case control study design, when assessing the contribution of the MTHFR T allele to disease processes. [ABSTRACT FROM AUTHOR]