85 research outputs found
Antioxidative potential of a combined therapy of anti TNFα and Zn acetate in experimental colitis.
AIM: To evaluate whether combination therapy with anti-tumour necrosis factor α
(TNFα) antibody and Zn acetate is beneficial in dextran sodium sulphate (DSS)
colitis.
METHODS: Colitis was induced in CD1-Swiss mice with 5% DSS for 7 d. The
experimental mice were then randomised into the following subgroups: standard
diet + DSS treated (induced colitis group); standard diet + DSS + subcutaneous 25
Όg anti-TNFα treated group; Zn acetate treated group + DSS + subcutaneous 25 Όg
anti-TNFα; standard diet + DSS + subcutaneous 6.25 Όg anti-TNFα treated group and
Zn acetate treated group + DSS + subcutaneous 6.25 Όg anti-TNFα. Each group of
mice was matched with a similar group of sham control animals. Macroscopic and
histological features were scored blindly. Homogenates of the colonic mucosa were
assessed for myeloperoxidase activity as a biochemical marker of inflammation and
DNA adducts (8OH-dG) as a measure of oxidative damage.
RESULTS: DSS produced submucosal erosions, ulcers, inflammatory cell infiltration
and cryptic abscesses which were reduced in both groups of mice receiving either
anti-TNFα alone or combined with zinc. The effect was more pronounced in the
latter group (vs Zn diet, P < 0.02). Myeloperoxidase activity (vs controls, P <
0.02) and DNA adducts, greatly elevated in the DSS fed colitis group (vs
controls, P < 0.05), were significantly reduced in the treated groups, with a
more remarkable effect in the group receiving combined therapy (vs standard diet,
P < 0.04).
CONCLUSION: DSS induces colonic inflammation which is modulated by the
administration of anti-TNFα. Combining anti-TNFα with Zn acetate offers marginal
benefit in colitis severity
Ontogenetic scaling patterns and functional anatomy of the pelvic limb musculature in emus (Dromaius novaehollandiae)
Emus (Dromaius novaehollandiae) are exclusively terrestrial, bipedal and cursorial ratites with some similar biomechanical characteristics to humans. Their growth rates are impressive, as their body mass increases eighty-fold from hatching to adulthood whilst maintaining the same mode of locomotion throughout life. These ontogenetic characteristics stimulate biomechanical questions about the strategies that allow emus to cope with their rapid growth and locomotion, which can be partly addressed via scaling (allometric) analysis of morphology. In this study we have collected pelvic limb anatomical data (muscle architecture, tendon length, tendon mass and bone lengths) and calculated muscle physiological cross sectional area (PCSA) and average tendon cross sectional area from emus across three ontogenetic stages (n = 17, body masses from 3.6 to 42 kg). The data were analysed by reduced major axis regression to determine how these biomechanically relevant aspects of morphology scaled with body mass. Muscle mass and PCSA showed a marked trend towards positive allometry (26 and 27 out of 34 muscles respectively) and fascicle length showed a more mixed scaling pattern. The long tendons of the main digital flexors scaled with positive allometry for all characteristics whilst other tendons demonstrated a less clear scaling pattern. Finally, the two longer bones of the limb (tibiotarsus and tarsometatarsus) also exhibited positive allometry for length, and two others (femur and first phalanx of digit III) had trends towards isometry. These results indicate that emus experience a relative increase in their muscle force-generating capacities, as well as potentially increasing the force-sustaining capacities of their tendons, as they grow. Furthermore, we have clarified anatomical descriptions and provided illustrations of the pelvic limb muscleâtendon units in emus
Small bowel enteroclysis with magnetic resonance imaging and computed tomography in patients with failed and uncertain passage of a patency capsule
<p>Abstract</p> <p>Background</p> <p>Video capsule enteroscopy (VCE) has revolutionized small bowel imaging, enabling visual examination of the mucosa of the entire small bowel, while MR enteroclysis (MRE) and CT enteroclysis (CTE) have largely replaced conventional barium enteroclysis. A new indication for MRE and CTE is the clinical suspicion of small bowel strictures, as indicated by delayed or non-delivery of a test capsule given before a VCE examination, to exclude stenosis. The aim of this study was to determine the clinical value of subsequent MRE and CTE in patients in whom a test capsule did not present itself in due time.</p> <p>Methods</p> <p>Seventy-five consecutive patients were identified with a delayed or unnoticed delivery of the test capsule. Seventy patients consented to participate and underwent MRE (44) or CTE (26). The medical records and imaging studies were retrospectively reviewed and symptoms, laboratory results and imaging findings recorded.</p> <p>Results</p> <p>Lesions compatible with Crohns disease were shown by MRE in 5 patients, by CTE in one and by VCE in four, one of whom had lesions on MRE. In patients without alarm symptoms and findings (weight loss, haematochezia, anaemia, nocturnal diarrheoa, ileus, fistula, abscess and abnormal blood tests) imaging studies did not unveil any such lesion. VCE's were performed in only 20 patients, mainly younger than 50 years of age, although no stenotic lesion was shown by MRE and CTE. In the remaining 50 patients no VCE or other endoscopic intervention was performed indicating that the referring physician was content with the diagnostic information from MRE or CTE.</p> <p>Conclusion</p> <p>The diagnostic value of MRE and CTE is sufficient for clinical management of most patients with suspected small bowel disease, and thus VCE may be omitted or at least postponed for later usage.</p
Expression and function of human hemokinin-1 in human and guinea pig airways
<p>Abstract</p> <p>Background</p> <p>Human hemokinin-1 (hHK-1) and endokinins are peptides of the tachykinin family encoded by the <it>TAC4 </it>gene. <it>TAC4 </it>and hHK-1 expression as well as effects of hHK-1 in the lung and airways remain however unknown and were explored in this study.</p> <p>Methods</p> <p>RT-PCR analysis was performed on human bronchi to assess expression of tachykinin and tachykinin receptors genes. Enzyme immunoassay was used to quantify hHK-1, and effects of hHK-1 and endokinins on contraction of human and guinea pig airways were then evaluated, as well as the role of hHK-1 on cytokines production by human lung parenchyma or bronchi explants and by lung macrophages.</p> <p>Results</p> <p>In human bronchi, expression of the genes that encode for hHK-1, tachykinin NK<sub>1</sub>-and NK<sub>2</sub>-receptors was demonstrated. hHK-1 protein was found in supernatants from explants of human bronchi, lung parenchyma and lung macrophages. Exogenous hHK-1 caused a contractile response in human bronchi mainly through the activation of NK<sub>2</sub>-receptors, which blockade unmasked a NK<sub>1</sub>-receptor involvement, subject to a rapid desensitization. In the guinea pig trachea, hHK-1 caused a concentration-dependant contraction mainly mediated through the activation of NK<sub>1</sub>-receptors. Endokinin A/B exerted similar effects to hHK-1 on both human bronchi and guinea pig trachea, whereas endokinins C and D were inactive. hHK-1 had no impact on the production of cytokines by explants of human bronchi or lung parenchyma, or by human lung macrophages.</p> <p>Conclusions</p> <p>We demonstrate endogenous expression of <it>TAC4 </it>in human bronchi, the encoded peptide hHK-1 being expressed and involved in contraction of human and guinea pig airways.</p
Micromechanical Properties of Injection-Molded StarchâWood Particle Composites
The micromechanical properties of injection molded starchâwood particle composites were investigated as a function of particle content and humidity conditions.
The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness
of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence
were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density
and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starchâwood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that
the wood in the starch composites did not prevent water loss from the samples.Peer reviewe
Patient Perspectives of Patient-Controlled Analgesia (PCA) and Methods for Improving Pain Control and Patient Satisfaction
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