219 research outputs found
Design methodology and performance of an indraft wind tunnel
The design methodology and performance of Loughborough University’s new 1·9m × 1·3m, indraft wind tunnel is discussed in the following paper. To overcome severe spatial and financial constraints, a novel configuration was employed, with the inlet and exit placed adjacent to each other and opened to atmosphere. Using a fine filter
mesh, honeycomb, two turbulence reduction screens and a contraction ratio of 7·3, flow uniformity in the working area of the jet at
40ms-1 is shown to be within 0·3% deviation from the mean velocity, with turbulence intensity in the region of 0·15%. Working section boundary layer characteristics are shown to be consistent with that of a turbulent boundary layer growing along a flat plate, which originates at the point of inflection of the contraction. A maximum velocity of 46ms-1 was achieved from a 140kW motor, compared to a prediction of 44ms-1, giving an energy ratio of 1·42. Comparison
between theoretical and measured performance metrics indicate differences between the way modules perform when part of a wind
tunnel system compared to data gathered from test rigs
Retinal microvascular network attenuation in Alzheimer's disease
AbstractIntroductionCerebral small-vessel disease has been implicated in the development of Alzheimer's disease (AD). The retinal microvasculature enables the noninvasive visualization and evaluation of the systemic microcirculation. We evaluated retinal microvascular parameters in a case-control study of AD patients and cognitively normal controls.MethodsRetinal images were computationally analyzed and quantitative retinal parameters (caliber, fractal dimension, tortuosity, and bifurcation) measured. Regression models were used to compute odds ratios (OR) and confidence intervals (CI) for AD with adjustment for confounders.ResultsRetinal images were available in 213 AD participants and 294 cognitively normal controls. Persons with lower venular fractal dimension (OR per standard deviation [SD] increase, 0.77 [CI: 0.62–0.97]) and lower arteriolar tortuosity (OR per SD increase, 0.78 [CI: 0.63–0.97]) were more likely to have AD after appropriate adjustment.DiscussionPatients with AD have a sparser retinal microvascular network and retinal microvascular variation may represent similar pathophysiological events within the cerebral microvasculature of patients with AD
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The Gsp-1 genes encode the 1 wheat arabinogalactan peptide
Western blotting, ELISA and 1H-NMR spectroscopy showed that RNAi down-regulation of the wheat Gsp-1 gene resulted in reduced contents of both arabinogalactan peptide (AGP) and grain softness protein (GSP-1) in mature wheat grains confirming that these components are encoded by the same gene. A small increase in grain hardness and decrease in the viscosity of aqueous extracts of the transgenic lines also indicated small effects on functional properties. Immunolocalisation using a novel wheat AGP monoclonal antibody in conjunction with confocal microscopy showed that the major form of AGP which was eliminated in knockout lines is located within the cell, probably in the vacuole, and not in the plasma membrane or cell wall. However, clear localisation of the AGP epitope to the plasma membrane was observed in both control and transgenic lines and probably resulted from the presence of one or more separate forms of arabinogalactan protein. The existence of such additional form(s) was also indicated by 1H-NMR spectroscopy which showed that the ratio of arabinose to galactose differed between the control and transgenic line
A Single-Arm, Proof-Of-Concept Trial of Lopimune (Lopinavir/Ritonavir) as a Treatment for HPV-Related Pre-Invasive Cervical Disease
BACKGROUND:
Cervical cancer is the most common female malignancy in the developing nations and the third most common cancer in women globally. An effective, inexpensive and self-applied topical treatment would be an ideal solution for treatment of screen-detected, pre-invasive cervical disease in low resource settings.
METHODS:
Between 01/03/2013 and 01/08/2013, women attending Kenyatta National Hospital's Family Planning and Gynaecology Outpatients clinics were tested for HIV, HPV (Cervista®) and liquid based cervical cytology (LBC -ThinPrep®). HIV negative women diagnosed as high-risk HPV positive with high grade squamous intraepithelial lesions (HSIL) were examined by colposcopy and given a 2 week course of 1 capsule of Lopimune (CIPLA) twice daily, to be self-applied as a vaginal pessary. Colposcopy, HPV testing and LBC were repeated at 4 and 12 weeks post-start of treatment with a final punch biopsy at 3 months for histology. Primary outcome measures were acceptability of treatment with efficacy as a secondary consideration.
RESULTS:
A total of 23 women with HSIL were treated with Lopimune during which time no adverse reactions were reported. A maximum concentration of 10 ng/ml of lopinavir was detected in patient plasma 1 week after starting treatment. HPV was no longer detected in 12/23 (52.2%, 95%CI: 30.6-73.2%). Post-treatment cytology at 12 weeks on women with HSIL, showed 14/22 (63.6%, 95%CI: 40.6-82.8%) had no dysplasia and 4/22 (18.2%, 95%CI: 9.9-65.1%) were now low grade demonstrating a combined positive response in 81.8% of women of which 77.8% was confirmed by histology. These data are supported by colposcopic images, which show regression of cervical lesions.
CONCLUSIONS:
These results demonstrate the potential of Lopimune as a self-applied therapy for HPV infection and related cervical lesions. Since there were no serious adverse events or detectable post-treatment morbidity, this study indicates that further trials are clearly justified to define optimal regimes and the overall benefit of this therapy.
TRIAL REGISTRATION:
ISRCTN Registry 48776874
Replication of EPHA1 and CD33 associations with late-onset Alzheimer's disease: a multi-centre case-control study
<p>Abstract</p> <p>Background</p> <p>A recently published genome-wide association study (GWAS) of late-onset Alzheimer's disease (LOAD) revealed genome-wide significant association of variants in or near <it>MS4A4A, CD2AP, EPHA1 </it>and <it>CD33</it>. Meta-analyses of this and a previously published GWAS revealed significant association at <it>ABCA7 </it>and <it>MS4A</it>, independent evidence for association of <it>CD2AP, CD33 </it>and <it>EPHA1 </it>and an opposing yet significant association of a variant near <it>ARID5B</it>. In this study, we genotyped five variants (in or near <it>CD2AP, EPHA1, ARID5B</it>, and <it>CD33</it>) in a large (2,634 LOAD, 4,201 controls), independent dataset comprising six case-control series from the USA and Europe. We performed meta-analyses of the association of these variants with LOAD and tested for association using logistic regression adjusted by age-at-diagnosis, gender, and <it>APOE ε4 </it>dosage.</p> <p>Results</p> <p>We found no significant evidence of series heterogeneity. Associations with LOAD were successfully replicated for <it>EPHA1 </it>(rs11767557; OR = 0.87, p = 5 × 10<sup>-4</sup>) and <it>CD33 </it>(rs3865444; OR = 0.92, p = 0.049), with odds ratios comparable to those previously reported. Although the two <it>ARID5B </it>variants (rs2588969 and rs494288) showed significant association with LOAD in meta-analysis of our dataset (p = 0.046 and 0.008, respectively), the associations did not survive adjustment for covariates (p = 0.30 and 0.11, respectively). We had insufficient evidence in our data to support the association of the <it>CD2AP </it>variant (rs9349407, p = 0.56).</p> <p>Conclusions</p> <p>Our data overwhelmingly support the association of <it>EPHA1 </it>and <it>CD33 </it>variants with LOAD risk: addition of our data to the results previously reported (total n > 42,000) increased the strength of evidence for these variants, providing impressive p-values of 2.1 × 10<sup>-15 </sup>(<it>EPHA1</it>) and 1.8 × 10<sup>-13 </sup>(<it>CD33</it>).</p
Activation of the Endonuclease that Defines mRNA 3' Ends Requires Incorporation into an 8-Subunit Core Cleavage and Polyadenylation Factor Complex
Cleavage and polyadenylation factor (CPF/CPSF) is a multi-protein complex essential for formation of eukaryotic mRNA 3' ends. CPF cleaves pre-mRNAs at a specific site and adds a poly(A) tail. The cleavage reaction defines the 3' end of the mature mRNA, and thus the activity of the endonuclease is highly regulated. Here, we show that reconstitution of specific pre-mRNA cleavage with recombinant yeast proteins requires incorporation of the Ysh1 endonuclease into an eight-subunit "CPFcore" complex. Cleavage also requires the accessory cleavage factors IA and IB, which bind substrate pre-mRNAs and CPF, likely facilitating assembly of an active complex. Using X-ray crystallography, electron microscopy, and mass spectrometry, we determine the structure of Ysh1 bound to Mpe1 and the arrangement of subunits within CPFcore. Together, our data suggest that the active mRNA 3' end processing machinery is a dynamic assembly that is licensed to cleave only when all protein factors come together at the polyadenylation site
Intensive versus Guideline Blood Pressure and Lipid Lowering in Patients with Previous Stroke: Main Results from the Pilot 'Prevention of Decline in Cognition after Stroke Trial' (PODCAST) Randomised Controlled Trial.
BACKGROUND: Stroke is associated with the development of cognitive impairment and dementia. We assessed the effect of intensive blood pressure (BP) and/or lipid lowering on cognitive outcomes in patients with recent stroke in a pilot trial. METHODS: In a multicentre, partial-factorial trial, patients with recent stroke, absence of dementia, and systolic BP (SBP) 125-170 mmHg were assigned randomly to at least 6 months of intensive (target SBP <125 mmHg) or guideline (target SBP <140 mmHg) BP lowering. The subset of patients with ischaemic stroke and total cholesterol 3.0-8.0 mmol/l were also assigned randomly to intensive (target LDL-cholesterol <1.3 mmol/l) or guideline (target LDL-c <3.0 mmol/l) lipid lowering. The primary outcome was the Addenbrooke's Cognitive Examination-Revised (ACE-R). RESULTS: We enrolled 83 patients, mean age 74.0 (6.8) years, and median 4.5 months after stroke. The median follow-up was 24 months (range 1-48). Mean BP was significantly reduced with intensive compared to guideline treatment (difference -10·6/-5·5 mmHg; p<0·01), as was total/LDL-cholesterol with intensive lipid lowering compared to guideline (difference -0·54/-0·44 mmol/l; p<0·01). The ACE-R score during treatment did not differ for either treatment comparison; mean difference for BP lowering -3.6 (95% CI -9.7 to 2.4), and lipid lowering 4.4 (95% CI -2.1 to 10.9). However, intensive lipid lowering therapy was significantly associated with improved scores for ACE-R at 6 months, trail making A, modified Rankin Scale and Euro-Qol Visual Analogue Scale. There was no difference in rates of dementia or serious adverse events for either comparison. CONCLUSION: In patients with recent stroke and normal cognition, intensive BP and lipid lowering were feasible and safe, but did not alter cognition over two years. The association between intensive lipid lowering and improved scores for some secondary outcomes suggests further trials are warranted. TRIAL REGISTRATION: ISRCTN ISRCTN85562386.The trial was funded equally by grants from Alzheimer’s Society and Stroke Association in the UK. There was no commercial support for the trial, and antihypertensive and lipid lowering drugs were prescribed by the responsible physician and sourced locally. The grant applicants conceived and designed the trial and wrote the protocol. Study data were collected, monitored, and analysed by the PODCAST Coordinating Centre in Nottingham, UK. Analysis, interpretation, and report writing were done independently of the funders and sponsor. The corresponding author and two other authors (PS, LW) had full access to all the data in the study; additionally, the corresponding author had final responsibility for the decision to submit for publication, and is the guarantor for the study. This study is registered as ISRCTN85562386 (http://www.isrctn.com/ISRCTN85562386)
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