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Verocytotoxigenic Escherichia coli (VTEC) are highly significant zoonotic threats to public health, and have been the causative agent implicated in numerous high-profile outbreaks affecting large numbers of people. Serovar O157 is most frequently linked with human illness; however, other serovars, such as O26, O103, O111 and O145, have also been implicated. This study aimed to characterize the prevalence and virulence determinants of these five serovars in Irish dairy farm herds, and their milk. Using real-time PCR (RTi-PCR), bovine rectal faecal swabs and raw milk samples, along with milk filters, were screened for the presence of vt genes. Positive samples were then screened for the five serovars using sero-specific PCR. Serovar-positive samples were subjected to immunomagnetic separation, to isolate viable VTEC strains. These isolates were subsequently screened for four virulence factors: vt1, vt2, eaeA and hlyA. Three hundred and eighty six of the 600 rectal faecal swabs, 85 of the 117 milk-filters and 43 of the 120 bulk-tank milk samples, were positive for vt genes. From these 514 total vt-positive samples, 58 O26, 162 O103, 1 O111, 324 O145 and 26 O157 positives were detected by sero-specific RTi-PCR. Immunomagnetic separation yielded 12 O26, 26 O103, 0 O111, 19 O145 and 10 O157 isolates. Ten of these isolates contained at least one of the four virulence determinants screened for (i.e. vt1, vt2, eaeA and hlyA). Of these 10 isolates, pulsed-field gel electrophoresis showed that two of the O26 isolates from different farms were indistinguishable. Two O157 isolates were also indistinguishable. This study found serovars O103 and O145 to be the most prevalent in samples tested. Apart from the occurrence of VTEC in dairy herds, this study shows a high occurrence of vt genes in the environment, creating the possibility of horizontal gene transfer and emergence of new VTEC strains. [ABSTRACT FROM AUTHOR]

Activation of the small GTPase RhoA following angiotensin II stimulation is known to result in actin reorganization and stress fiber formation. Full activation of RhoA, by angiotensin II, depends on the scaffolding protein β-arrestin 1, although the mechanism behind its involvement remains elusive. Here we uncover a novel partner and function for β-arrestin 1, namely, in binding to ARHGAP21 (also known as ARHGAP10), a known effector of RhoA activity, whose GTPase-activating protein (GAP) function it inhibits. Using yeast two-hybrid screening, a peptide array, in vitro binding studies, truncation analyses, and coimmunoprecipitation techniques, we show that β-arrestin 1 binds directly to ARHGAP21 in a region that transects the RhoA effector GAP domain. Moreover, we show that the level of a complex containing β-arrestin 1 and ARHGAP21 is dynamically increased following angiotensin stimulation and that the kinetics of this interaction modulates the temporal activation of RhoA. Using information gleaned from a peptide array, we developed a cell-permeant peptide that serves to inhibit the interaction of these proteins. Using this peptide, we demonstrate that disruption of the β-arrestin 1/ARHGAP21 complex results in a more active ARHGAP21, leading to less-efficient signaling via the angiotensin II type 1A receptor and, thereby, attenuation of stimulated stress fiber formation [ABSTRACT FROM AUTHOR]

The Severn Bridge, completed in 1966, was the first suspension bridge to adopt a streamlined box girder deck that reduced the dead weight and improved aerodynamic performance. The 988 m span bridge crosses the estuary of the River Severn and is an important asset within the UK highway network. In 2006, the UK's Highways Agency, through the concessionaire Severn River Crossing plc, commissioned a programme of internal intrusive examination of the main suspension cables of the Severn Bridge with Faber-Maunsell/Weidlinger acting as consultants for the inspection. The information obtained during these investigations provided the basic data for use in a formal strength assessment of the suspension cables undertaken by Mott MacDonald, the UK government's representative for the Severn Crossings concession. Analytical techniques developed over the past 3 years have enabled the adoption of limit state principles for the assessment in line with UK practice. In addition, deterioration modelling has been developed to improve understanding of the current condition of the cables and to assist in the future management of the bridge. In parallel with the strength assessment, process maintenance management strategies have been developed and implemented that have enabled the continued safe operation of the bridge. [ABSTRACT FROM AUTHOR]

Background and Purpose: Increases in intracellular cyclic AMP (cAMP) augment the release/secretion of glucagon-like peptide-1 (GLP-1). As cAMP is hydrolysed by cAMP phosphodiesterases (PDEs), we determined the role of PDEs and particularly PDE4 in regulating GLP-1 release.Experimental Approach: GLP-1 release, PDE expression and activity were investigated using rats and GLUTag cells, a GLP-1-releasing cell line. The effects of rolipram, a selective PDE4 inhibitor both in vivo and in vitro and stably overexpressed catalytically inactive PDE4D5 (D556A-PDE4D5) mutant in vitro on GLP-1 release were investigated.Key Results: Rolipram (1.5 mg x kg(-1) i.v.) increased plasma GLP-1 concentrations approximately twofold above controls in anaesthetized rats and enhanced glucose-induced GLP-1 release in GLUTag cells (EC(50) approximately 1.2 nmol x L(-1)). PDE4D mRNA transcript and protein were detected in GLUTag cells using RT-PCR with gene-specific primers and Western blotting with a specific PDE4D antibody respectively. Moreover, significant PDE activity was inhibited by rolipram in GLUTag cells. A GLUTag cell clone (C1) stably overexpressing the D556A-PDE4D5 mutant, exhibited elevated intracellular cAMP levels and increased basal and glucose-induced GLP-1 release compared with vector-transfected control cells. A role for intracellular cAMP/PKA in enhancing GLP-1 release in response to overexpression of D556A-PDE4D5 mutant was demonstrated by the finding that the PKA inhibitor H89 reduced both basal and glucose-induced GLP-1 release by 37% and 39%, respectively, from C1 GLUTag cells.Conclusions and Implications: PDE4D may play an important role in regulating intracellular cAMP linked to the regulation of GLP-1 release. [ABSTRACT FROM AUTHOR]

Radiometric measurements of the angular distribution of infrared (8-12 mm) radiation from a field site in a semiarid sandy soil location are reported. The aim of this study is to investigate the variation of emitted infrared radiation with zenith view angle. The motivation arises through the need to correct wide-field-of-view satellite measurements of land surface temperature for surface-induced zenith-angle effects. A new self-calibrating, scanning radiometer is used to acquire near-continuous measurements for zenith view angles up to 708. The results suggest that, during the day, the measured brightness temperature is evidently affected by a relation between solar illumination and viewing angle through differential heating and shading. During the nighttime, a significant angular variation (up to 8%) in surface emissivity is discerned. The angular behavior of surface emission at night stemming from this variation is accurately modeled using the d-Eddington approximation. Implications for satellite measurements of land surface temperature from the Advanced Very High Resolution Radiometer (AVHRR)-2, Geostationary Meteorological Satellite (GMS)-5, Moderate-Resolution Imaging Spectroradiometer (MODIS), and Along-Track Scanning Radiometer (ATSR)-2/Advanced Along-Track Scanning Radiometer (AATSR) are discussed. [ABSTRACT FROM AUTHOR]

The long term outcome of 21 children with extrahepatic portal hypertension secondary to portal vein thrombosis managed by surgical intervention was evaluated. Portosystemic shunts, used primarily in nine patients (eight central splenorenal, one mesocaval) after conservative treatment had failed, had no associated mortality and a 56% patency rate. Five of these shunted patients had no further bleeding episodes and did not show encephalopathic impairment. Direct attack procedures-portoazygos operation (four patients) was associated with significant complications, including one fatality. Other direct approaches-oesophageal transection and variceal plication (five patients) had variable outcome. Splenectomy alone (three patients) ameliorated hypersplenism; however, further surgery for recurrent haemorrhage (two patients) was necessary. Endoscopic sclerotherapy controlled recurrent variceal bleeding (three patients) when it became available to the unit. Conservative treatment practised in five children had little success: two patients survived, two died from further haemorrhage, and one was lost to follow up. These results suggest that in centres without endoscopic expertise, and for patients who are sclerotherapy 'failures', surgery can be performed safely and achieve reasonable long term success rates in childhood extrahepatic portal hypertension. [ABSTRACT FROM AUTHOR]

Objective To assess the factors associated with loss of implant following penile prosthetic surgery and to make alterations in the management of patients to prevent this from occurring. Patients and methods A retrospective analysis was carried out of the factors associated with post-operative infection and erosion in 188 patients who underwent implantation of penile prostheses. A prospective study was then established in which 62 patients were managed by a set protocol designed to counteract the factors identified as being contributory to loss of implants in the retrospective review. Results In the retrospective study nine (4.8%) patients lost a prosthesis due to erosion. Erosion was noted to be more common with one type of implant which has since been modified. Infection was the cause of prosthesis loss in 12.2% of patients in the retrospective review. The new protocol resulted in a signi6cantly reduced infection rate in penile prostheses to 1.6% (P<0.05). Conclusion With attention to simple antiseptic prophylaxis, antibiotic penetration and continuing audit, a significant improvement in the loss of penile prostheses can be achieved along with a reduction in the amount of antibiotics prescribed. [ABSTRACT FROM AUTHOR]

- There is a paucity of data to determine if the insertion of a testicular prosthesis is effective in overcoming the psychological effects of an absent testis. A review of 25 patients who had had testicular prostheses showed a high overall level of satisfaction in the 19 patients who were traced. This satisfaction was subject to some qualification. [ABSTRACT FROM AUTHOR]

To prevent ascending urinary infection in patients following transurethral prostatectomy, we have studied the use of a topical antibacterial agent applied to the groin and external genitalia. A prospective randomized controlled trial was conducted, with 50 patients being treated by daily application of a 2% polynoxylin powder, and 50 patients acting as untreated controls. Patient age and duration of catheterization were similar in the treated and untreated groups. No significant benefit was seen in the treated cohort (P greater than 0.05) in terms of reduction in postoperative urinary infection. [ABSTRACT FROM AUTHOR]

To prevent ascending urinary infection in. patients following transurethral prostatectomy, we have studied the use of a topical antibacterial agent applied to the groin and external genitalia. A prospective randomized controlled trial was conducted, with 50 patients being treated by daily application of a 2% polynoxylin powder, and 50 patients acting as untreated controls. Patient age and duration of catheterization were similar in the treated and untreated groups. No significant benefit was seen in the treated cohort (P> 0.05) in terms of reduction in postoperative urinary infection. [ABSTRACT FROM AUTHOR]