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Background and Purpose: Urocortins (Ucns) 1, 2 and 3 are corticotropin-releasing factor (CRF)-related neuropeptides and may be involved in neural regulation of colonic motor functions. Nevertheless, details of the neural mechanism of action for Ucns have been unclear. We have, here, tested the hypothesis that Ucns act in the enteric nervous system (ENS) to influence colonic motor behaviour.Experimental Approach: We used intracellular recording with 'sharp' microelectrodes, followed by intraneuronal injection of biocytin, and immunohistochemical localization of CRF(1) and CRF(2) receptors in guinea pig colonic tissue.Key Results: Application of Ucn1 depolarized membrane potentials and elevated excitability in 58% of AH-type and 60% of S-type colonic myenteric neurons. In most of the neurons tested, depolarizing responses evoked by Ucn-1 were suppressed by the CRF(1) receptor antagonist NBI 27914, but were unaffected by the CRF(2) receptor antagonist antisauvagine-30. The selective CRF(2) receptor agonists, Ucn2 and Ucn3, evoked depolarizing responses in 12 and 8% of the AH-type myenteric neurons, respectively, and had no effect on S-type neurons. Antisauvagine-30, but not NBI 27914, suppressed these Ucn2- and Ucn3-evoked responses. Immunohistochemical staining identified CRF(1) as the predominant CRF receptor subtype expressed by ganglion cell somas, while CRF(2)-immunoreactive neuronal somas were sparse. Ucns did not affect excitatory synaptic transmission in the ENS.Conclusions and Implications: The results suggest that Ucns act as neuromodulators to influence myenteric neuronal excitability. The excitatory action of Ucn1 in myenteric neurons was primarily at CRF(1) receptors, and the excitatory action of Ucn2 and Ucn3 was at CRF(2) receptors. [ABSTRACT FROM AUTHOR]

1 This account reviews information on all aspects of the biology of Sarcocornia perennis that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history, and conservation. 2 Sarcocornia perennis (Miller) A.J. Scott ( Salicornia perennis Miller; Salicornia radicans Sm.; Arthrocnemum [ Arthrocnemon] perenne (Miller) Moss) of the European and African coasts is now considered also to include Salicornia virginica L., S. ambigua Michx. and S. gaudichaudiana Moq. of the Americas. Sarcocornia perennis is a spreading, jointed-stemmed, halophyte that differs from the closely related Salicornia in being a shrubby perennial and in aspects of inflorescence structure. In Britain, it is found mainly on the coasts of south-east England, on gravelly or sandy foreshores, and well-drained sediments of tidal salt marshes. 3 Sarcocornia perennis occurs relatively low in the tidal frame but only in well-drained situations, as seedling establishment and long-term survival are intolerant of highly reducing surface sediments. It has a role in the early stages of salt-marsh succession, sometimes as the primary colonist on sandy substrates. In southern Europe, its invasion may be facilitated by the raised clonal tussocks of Spartina maritima, a primary colonist; subsequently, S. perennis dominates the tussocks and supports their rapid radial and upward growth by trapping silt. Pollen flow from the high marsh species Sarcocornia fruticosa may allow invasion by hybrids between the two species. 4 Hybridization between the diploid S. perennis and octaploid S. fruticosa in south-west Spain has been confirmed by analysis of random amplified DNA (RAPDs). This has also clarified the relationship between the two subspecies present there (the widely distributed ssp. perennis and the more upright, rigid Iberian endemic ssp. alpini (Lag.) Castroviejo). 5 Sarcocornia perennis maintains low water potentials and a positive carbon balance under highly saline conditions. Salinity treatment had no effect on the efficiency of Photosystem II (Fv/Fm). Total germination was also unaffected by salinity up to 2%, although above this it was progressively inhibited; the reduction in germination at seawater concentrations was mainly osmotically enforced dormancy, which would promote dispersal by tides and currents. [ABSTRACT FROM AUTHOR]

Summary In many animal models transplanted livers are not rejected, even when there is a complete MHC mismatch between the donor and recipient and the recipient is not immunosuppressed. This distinguishes liver transplants from other organs, such as kidneys and hearts, which are rapidly rejected in mismatched individuals. Acceptance of transplanted livers in a rat model is not due to the absence of an immune response to the liver and there is a rapid, abortive response that is ultimately exhausted. Donor leucocytes transferred with the liver appear to be responsible for both liver acceptance and the abortive activation of the recipient’s T cells. The immune mechanism of liver transplant acceptance appears to be due to ‘death by neglect’ in which T cells are activated to express IL-2 and IFN-γ mRNA in the recipient lymphoid tissues, but not at adequate levels within the graft. Subsequently the activated T cells die leading to specific clonal deletion of liver donor-reactive T cells. These findings have important implications for liver transplant patients as immunosuppressive drugs that are given to prevent rejection can also interfere with this form of tolerance. In addition, it might be possible to modify the immunosuppressive drug treatment of transplant patients to promote the process of death by neglect of recipient alloreactive T cells. [ABSTRACT FROM AUTHOR]

Reviews information on the taxa of the leafless halphytic herb genus Salicornia L. (Chenopodiaceae). Morphology; Characteristics of several species found in Great Britain; Climatic and topographical limitations.

Summary Real-time quantitative reverse transcriptase–polymerase chain reaction (RT–PCR) is the method of choice for rapid and reproducible measurements of cytokine or growth factor expression in small samples. Fluorescence detection methods for monitoring real-time PCR include fluorogenic probes labelled with reporter and quencher dyes, such as Taqman probes or Molecular Beacons and the dsDNA-binding dye SYBR Green I. Fluorogenic (Taqman) probes for a range of human and rat cytokines and growth factors were tested for sensitivity and compared with an assay for SYBR Green I quantification using real-time fluorescence monitoring (PE Applied Biosystems Model 7700 sequence detector). SYBR Green I detection involved analysis of the melting temperature of the PCR product and measurement of fluorescence at the optimum temperature. Fluorogenic probes provided sensitive and reproducible detection of targets that ranged from low (<10 copies/reaction) to high (>107 copies/ reaction) expression. SYBR Green I gave reproducible quantification when the target gene was expressed at moderate to high levels (≥1000 copies/reaction), but did not give consistently reproducible quantification when the target gene was expressed at low levels. Although optimization of melting temperature improved the specificity of SYBR Green I detection, in our hands it did not equal the reproducible sensitivity and specificity of fluorogenic probes. The latter method is the first choice for measurement of low-level gene expression, although SYBR Green I is a simple and reproducible means to quantify genes that are expressed at moderate to high levels. [ABSTRACT FROM AUTHOR]

The hallmarks of chronic liver diseases are chronic inflammation, cellular damage, regeneration and fibrosis. An appreciation of intrahepatic molecular expression patterns in normal and diseased liver provides clues for understanding pathogenic pathways whilst studies of the structure and function of molecules implicated in liver disease provide insights into their potential as therapeutic targets. We have examined the expression, function, molecular structure and structure-function relationships of type IV dipeptidyl aminopeptidases. In particular, the roles of CD26/DPPIV in T-cell proliferation and chemotaxis and of fibroblast activation protein in human cirrhosis are discussed. We have investigated the pathogenesis of liver disease by chracterising patterns of cytokine and growth factor expression in experimental and human cirrhosis. We have quite recently expanded this approach to use differential gene expression analyses to elucidate overall pathways of gene activation and suppression in human cirrhosis. In addition, our detailed molecular and cellular studies of the mechanisms of spontaneous liver transplant tolerance have generated novel insights into this process. This review touches on these diverse aspects of liver function and disease. [ABSTRACT FROM AUTHOR]

Presents abstracts related to trauma surgery presented at the Royal Australasian College of Surgeons 1998 Annual Scientific Congress. 'Threat or Transfer--Best Practice,' by K. Boffard; 'When to Amputate,' by P.J. McGrath.

(1) A 2-year demographic study was made of four adjacent populations of Hieracium pilosella on contrasting soil types in Breckland, in order to examine whether the population fluxes were different. Three of the four sites were rabbit-grazed, hut at the fourth a rabbit-proof exclosure was constructed. (2) Recruitment of rosettes to all populations was the result of clonal growth, as seedling establishment failed to occur. However, sexual reproduction and clonal growth were closely linked; it was observed that an. immature inflorescence needed to he produced before the production of stolons and the development of rosettes at the ends of the stolons could occur. Plants senesced after undergoing reproduction. (3) Alt the populations showed overall exponential decay rates, upon which was super- imposed an annual rhythm or natality and mortality. Initially all four populations showed fairly similar overall exponential decay rates, but midway through the study the rate of decline abruptly increased in the populations growing in acidic sand and chalk so ii, with the result that one population became almost extinct, and in the other the age of the majority of individuals in the population consisted of young plants less than 05 years of age. (4) The absence of grazing resulted in the population in the exclosure consisting of a greater proportion of plants 2 years or older compared with the other sites. (5) The significance of these differences in the population fluxes at the sites is discussed in relation to changes in Breckland populations of H. pilosella reported earlier by Watt (1962), and to the exceptional drought of 1975-6. [ABSTRACT FROM AUTHOR]

Reverse transcriptase-PCR (RT-PCR) amplification of mRNA is often the only technique able to detect expression of cytokine mRNA in small samples. The aim of this work was to investigate the utility of a non-competitive RT-PCR which used external standards to quantitate TNF-α mRNA in liver biopsy specimens from liver transplant patients. It involved removal of aliquots from the PCR reaction at successive cycles, followed by dot-blotting of the samples onto nylon membrane and hybridization with a radioactively labelled internal probe. Phosphorimage analysis of the labelled membranes allowed quantitation of the relative amount of PCR product at successive cycles. Plots of log(counts) versus cycle number showed straight lines in the exponential phase of amplification. The slopes of these lines showed the efficiency of amplification, which ranged from 76 to 87% for liver biopsy samples. Estimation of liver biopsy levels of TNF-α in two separate PCR amplifications showed low inter-assay variability (r² = 0.98). Comparison of two separate cDNA syntheses also showed good correlation (r² = 0.81. P < 0.0001), although not as good as for the PCR alone. This shows that variation in efficiency of cDNA synthesis is likely to contribute as much or more to variability of the analysis as variations in PCR amplification. [ABSTRACT FROM AUTHOR]

Background Cord blood mononuclear cells have demonstrated specific immune responses to environmental allergens. Objective To establish whether the nature of this response is related to the level of maternal antenatal exposure to house dust mite (HDM) allergen and, hence, whether antenatal allergen avoidance may have a role in the prevention of allergic sensitization in children. Methods Children with a family history of asthma were recruited antenatally as subjects in a randomised controlled trial: the Childhood Asthma Prevention Study. HDM allergen (Der p 1) concentrations were measured in dust collected from the maternal bed at 36 weeks gestation. Cord blood mononuclear cells were stimulated in culture, separately, with phytohaemaglutinin (PHA) and HDM extract. Cytokine IL-4, IL-5, IL-10 and IFN-γ concentrations in supernatant were measured by ELISA. mRNA signals for these cytokines were measured using RT-PCR. Results The median concentration of HDM allergen was 18.4 µg/g (interquartile range 7.3–35.3 µg/g). Median concentrations of IL-4, IL-5, IL-10 and IFN-γ, after PHA stimulation were 4, 19, 401 and 1781 pg/mL, respectively. After HDM allergen stimulation the median concentrations were 0, 0, 20 and 14 pg/mL, respectively. The distribution of mRNA cytokine signals was similar. Neither cytokine protein concentrations nor cytokine mRNA signal levels were correlated with the concentration of HDM allergen in the mothers' beds at 36 weeks gestation. Conclusion These findings do not support the view that the prevention of allergic disease in children requires the institution of HDM avoidance interventions during pregnancy. [ABSTRACT FROM AUTHOR]

Language, cultural, and educational barriers complicate efforts to validate health status questionnaires that have been translated into Spanish. To overcome these problems, a prototype dual-language format was developed for the Arthritis Impact Measurement Scales. Validity testing with 72 patients diagnosed as having rheumatoid arthritis indicated high levels of test-retest reliability, item-to-scale internal consistency, and construct validity for both Anglo and Hispanic subjects. A technique for developing and pilot-testing a questionnaire written in a regional Spanish dialect is described. Linguistic considerations, questionnaire design, and other applications are discussed in light of the results obtained.