414 research outputs found
Site and mechanism of enhanced gastrointestinal absorption of aluminum by citrate
Site and mechanism of enhanced gastrointestinal absorption of aluminum by citrate. Clinical and experimental studies have shown that citrate markedly enhances the intestinal absorption of aluminum (Al), but the site and mechanism of enhanced absorption are unknown. To determine where in the gastrointestinal tract aluminum citrate (Alcitr) was absorbed, Alcitr was gavaged with D-[1-3H] glucose in male Sprague-Dawley rats. Plasma Al levels increased rapidly and simultaneously peaked with D-[1-3G] glucose, suggesting early proximal bowel absorption. In in vitro duodenal and jejunal everted gut preparations, Alcitr incubation resulted in increased tissue Al levels and markedly enhanced transmural transport of Al and citr. Unlike citr, the transmural movement of Al was independent of temperature (37°C vs. 4°C). On the other hand, Al lactate (al Lac) increased tissue associated Al levels but had no effect on transmural Al movement. To determine if this large flux of Al following Alcitr administration was due to paracellular movement, ruthenium red and Ussing chamber studies were used to evaluate the morphologic and functional integrity of cellular tight junctions. Alcitr, as opposed to A1C13, markedly increased ruthenium red deposits in intercellular spaces, especially around goblet cells, and induced a prolonged significant reduction in transmural resistance. Alcitr also resulted in rapid and nearly complete (99.7%) chelation of free calcium, an event known to disrupt cellular tight junction integrity. Taken together, these data suggest that enhanced Al absorption following administration of Alcitr occurs in the proximal bowel via the paracellular pathway due to the opening of cellular tight junctions
Augmenter of liver regeneration enhances the success rate of fetal pancreas transplantation in rodents
Background. Treatment of fetal pancreas (FP) isografts with insulin- like growth factor-I greatly improves the rate of conversion to euglycemia in diabetic rats. Complete knowledge of other factors that may facilitate the engraftment and function of FP in vivo is still embryonic. Augmenter of liver regeneration (ALR) is a newly described polypeptide growth factor found in weanling rat livers. ALR has trophic effects on regenerating liver. We studied the effects of in situ administration of this agent on FP isografts in rats. Methods. Streptozotocin-diabetic Lewis rats (blood glucose >300 mg/dl) received 16 FP isografts transplanted intramuscularly. ALR was delivered from day 1 through day 14, in doses of 40 or 400 ng/kg/d. Animals were followed for 3 months with serial weights and blood glucose monitoring. These animals were compared with those treated with vehicle alone. Results. Of the group treated with ALR at 40 ng/kg/day for 14 days, 89% (eight of nine) were euglycemic (P=0.0003). Of the group treated with ALR at 400 ng/kg/day for 14 days, 88% (seven of eight) were euglycemic (P=0.0007). Of the group treated with vehicle alone, none of the six were euglycemic. Euglycemia is defined here as glucose<200 mg/dl for 3 days. Pathology of the intramuscular transplant site showed patches of islet tissue embedded in fat. These patches demonstrated insulin immunoreactivity. Conclusions. Diabetes was reversed in a significantly greater proportion of FP + ALR-treated recipients than those animals treated with vehicle alone. Local delivery of growth factors my be used as an adjunct to FP transplantation to improve the rate of success. This in situ model may be useful to further evaluate other soluble factors
The writing on the wall: the concealed communities of the East Yorkshire horselads
This paper examines the graffiti found within late nineteenth and early-twentieth century farm buildings in the Wolds of East Yorkshire. It suggests that the graffiti were created by a group of young men at the bottom of the social hierarchy - the horselads – and was one of the ways in which they constructed a distinctive sense of communal identity, at a particular stage in their lives. Whilst it tells us much about changing agricultural regimes and social structures, it also informs us about experiences and attitudes often hidden from official histories and biographies. In this way, the graffiti are argued to inform our understanding, not only of a concealed community, but also about their hidden histor
Haemoglobin mass and running time trial performance after recombinant human erythropoietin administration in trained men
<p>Recombinant human erythropoietin (rHuEpo) increases haemoglobin mass (Hbmass) and maximal oxygen uptake (v˙ O2 max).</p>
<p>Purpose: This study defined the time course of changes in Hbmass, v˙ O2 max as well as running time trial performance
following 4 weeks of rHuEpo administration to determine whether the laboratory observations would translate into actual
improvements in running performance in the field.</p>
<p>Methods: 19 trained men received rHuEpo injections of 50 IUNkg21 body mass every two days for 4 weeks. Hbmass was
determined weekly using the optimized carbon monoxide rebreathing method until 4 weeks after administration. v˙ O2 max
and 3,000 m time trial performance were measured pre, post administration and at the end of the study.</p>
<p>Results: Relative to baseline, running performance significantly improved by ,6% after administration (10:3061:07 min:sec
vs. 11:0861:15 min:sec, p,0.001) and remained significantly enhanced by ,3% 4 weeks after administration
(10:4661:13 min:sec, p,0.001), while v˙ O2 max was also significantly increased post administration
(60.765.8 mLNmin21Nkg21 vs. 56.066.2 mLNmin21Nkg21, p,0.001) and remained significantly increased 4 weeks after
rHuEpo (58.065.6 mLNmin21Nkg21, p = 0.021). Hbmass was significantly increased at the end of administration compared to
baseline (15.261.5 gNkg21 vs. 12.761.2 gNkg21, p,0.001). The rate of decrease in Hbmass toward baseline values post
rHuEpo was similar to that of the increase during administration (20.53 gNkg21Nwk21, 95% confidence interval (CI) (20.68,
20.38) vs. 0.54 gNkg21Nwk21, CI (0.46, 0.63)) but Hbmass was still significantly elevated 4 weeks after administration
compared to baseline (13.761.1 gNkg21, p<0.001).</p>
<p>Conclusion: Running performance was improved following 4 weeks of rHuEpo and remained elevated 4 weeks after
administration compared to baseline. These field performance effects coincided with rHuEpo-induced elevated v˙ O2 max and
Hbmass.</p>
Hepatic Abnormalities Associated with Aluminum Loading in Piglets
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141476/1/jpen0293.pd
Forced Solid-State Interactions for the Selective “Turn-On” Fluorescence Sensing of Aluminum Ions in Water Using a Sensory Polymer Substrate
Selective and sensitive solid sensory substrates for detecting Al(III) in pure
water are reported. The material is a flexible polymer film that can be handled and exhibits gel
behavior and membrane performance. The film features a chemically anchored salicylaldehyde
benzoylhydrazone derivative as an aluminum ion fluorescence sensor. A novel procedure for
measuring Al(III) at the ppb level using a single solution drop in 20 min was developed. In this
procedure, a drop was allowed to enter the hydrophilic material for 15 min before a 5 min
drying period. The process forced the Al(III) to interact with the sensory motifs within the
membrane before measuring the fluorescence of the system. The limit of detection of Al(III)
was 22 ppm. Furthermore, a water-soluble sensory polymer containing the same sensory
motifs was developed with a limit of detection of Al(III) of 1.5 ppb, which was significantly
lower than the Environmental Protection Agency recommendations for drinking water.Spanish Ministerio de Economía
y Competitividad-Feder
(MAT2011-22544) and by the Consejería
de Educación - Junta
de Castilla y León (BU232U13)
Shot at Dawn: Late Photography and the Anti-War Memorial
The military executions of World War One are the subject of Chloe Dewe
Mathews’s 2014 photographic series Shot at Dawn. These events—in
which hundreds of soldiers were court-martialled and executed for
cowardice and desertion—remain controversial, without consensus or
established collective narrative. This article charts historic negotiations
with the subject but also considers more recent efforts to integrate these
proceedings within memorial practice. World War One remembrance
activities, whilst diverse, have often emphasised sacrifice, heroism and
community. Correspondingly, participation and engagement were core
values in the major British World War One centenary arts project, titled
14-18 NOW, from which Shot at Dawn was commissioned. Chloe Dewe
Mathews’s contribution to the programme, however, presents a
photographic aesthetic of resistance to the principles of inclusivity and
remembrance elsewhere embraced by the project. As such, the work
challenges the consensual politics of commemoration and—through the
practices of late photography, land art and performance pilgrimage—
substitutes trauma and forgetfulness for reconciliation and memory
The development of direct extrusion-injection moulded zein matrices as novel oral controlled drug delivery systems
Purpose: To evaluate the potential of zein as a sole excipient for controlled release formulations prepared by hot melt extrusion. Methods: Physical mixtures of zein, water and crystalline paracetamol were hot melt extruded (HME) at 80°C and injection moulded (IM) into caplet forms. HME-IM Caplets were characterised using differential scanning calorimetry, ATR-FTIR spectroscopy, scanning electron microscopy and powder X-ray diffraction. Hydration and drug release kinetics of the caplets were investigated and fitted to a diffusion model. Results: For the formulations with lower drug loadings, the drug was found to be in the non-crystalline state, while for the ones with higher drug loadings paracetamol is mostly crystalline. Release was found to be largely independent of drug loading but strongly dependent upon device dimensions, and predominately governed by a Fickian diffusion mechanism, while the hydration kinetics shows the features of Case II diffusion. Conclusions: In this study a prototype controlled release caplet formulation using zein as the sole excipient was successfully prepared using direct HME-IM processing. The results demonstrated the unique advantage of the hot melt extruded zein formulations on the tuneability of drug release rate by alternating the device dimensions
Living-donor parathyroid allotransplantation for therapy-refractory postsurgical persistent hypoparathyroidism in a nontransplant recipient – three year results: a case report
Quality, Features, and Presence of Behavior Change Techniques in Mobile Apps Designed to Improve Physical Activity in Pregnant Women: Systematic Search and Content Analysis
Background: Physical activity during pregnancy is associated with a variety of health benefits for the mother and her child. Despite the many health benefits of physical activity during pregnancy, few women participate in regular physical activity during pregnancy. ehealth platforms, such as the internet and mobile applications (apps), are now altering how women access information about their pregnancy and have become an important information source for pregnant women. Whilst the use of pregnancy-related apps has significantly increased among pregnant women, very little is known about their theoretical underpinnings, including their utilisation of behaviour change techniques. This is despite research suggesting the inclusion of behaviour change techniques in ehealth interventions can play an important role in improving, supporting and maintain healthy behaviours, including physical activity. Objective: To review physical activity apps designed for pregnant women with a focus on app content, quality and features, and the presence and efficacy of Behaviour Change Techniques (BCTs). Methods: A systematic search in the Australian AppStore and GooglePlay stores using search terms relating to exercise and pregnancy. App features and quality was assessed using the 19-item Mobile Application Rating Scale (MARS) and a taxonomy of BCTs was used to determine presence of BCTs (26 items). BCTs previously demonstrating efficacy in behaviour change during pregnancy were also identified from a review of the literature. Results: Nineteen exercise apps were deemed eligible for this review and accessed via GooglePlay (n=13) or AppStore (n=6). MARS Overall Quality scores showed moderate app quality (m=3.5, SD=0.52). Functionality was the highest scoring MARS domain (m=4.2, SD=0.5), followed by Aesthetics (m=3.7, SD=0.6) and Information Quality (m=3.16, SD=0.42). Engagement (m=3.01, SD=0.9), Subjective App Quality (m=2.54, SD=0.64) and Likelihood for Behavioural Impact (m=2.5, SD=0.6) were the lowest scoring MARS domains. All 19 apps were found to incorporate at least two BCTs (m=4.74, SD=2.51, range=2–10), with provide instructions (95%) and provide information on consequences (89%) being the most common BCTs. Eleven apps included BCTs that previously demonstrated efficacy for behaviour change during pregnancy, the most common of these being provide opportunities for social comparison (n=8) and prompt self-monitoring of behaviour (n=7). Conclusions: Apps to improve exercise in pregnant women were functional and aesthetically pleasing, with overall moderate quality. However, the incorporation of BCTs was low, with the prevalence of BCTs previously demonstrating efficacy in promoting and/or supporting physical activity during pregnancy scarce. Thus, it is unlikely that apps reviewed in this study will effectively promote and/or support the exercise behaviours among pregnant women. Clinical Trial: Not required.Additional co-authors: Michelle Mottola; Taniya S Nagpal; Lisa Vincze; Stephanie Schoepp
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