69 resultados para Restoration thickness

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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Cytochrome P450 oxidoreductase (POR) supplies electrons from NADPH to steroid and drug metabolizing reactions catalyzed by the cytochrome P450s located in endoplasmic reticulum. Mutations in human POR cause a wide spectrum of disease ranging from disordered steroidogenesis to sexual differentiation. Previously we and others have shown that POR mutations can lead to reduced activities of steroidogenic P450s CYP17A1, CYP19A1 and CYP21A1. Here we are reporting that mutations in the FMN binding domain of POR may reduce CYP3A4 activity, potentially influencing drug and steroid metabolism; and the loss of CYP3A4 activity may be correlated to the reduction of cytochrome b(5) by POR. Computational molecular docking experiments with a FMN free structural model of POR revealed that an external FMN could be docked in close proximity to the FAD moiety and receive electrons donated by NADPH. Using FMN supplemented assays we have demonstrated restoration of the defective POR activity in vitro.

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Conventional time-domain optical coherence tomography (OCT) has become an important tool for following dry or exudative age-related macular degeneration (AMD). Fourier-domain three-dimensional (3D) OCT was recently introduced. This study tested the reproducibility of 3D-OCT retinal thickness measurements in patients with dry and exudative AMD.

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The aim of the study was to assess the thickness of softened enamel removed by toothbrushing. Human enamel specimens were indented with a Knoop diamond. Softening was performed with citric acid or orange juice. The specimens were brushed in a brushing machine with a manual soft toothbrush in toothpaste slurry or in artificial saliva. Enamel loss was calculated from the change in indentation depth of the same indent before and after abrasion. Mean surface losses (95% confidence interval) were recorded in treatment groups (in nanometers): (1) citric acid, abrasion with slurry = 339 (280-398); (2) citric acid, abrasion with artificial saliva = 16 (5-27); (3) orange juice, abrasion with slurry = 268 (233-303); (4) orange juice, abrasion with artificial saliva = 14 (5-23); (5) no softening, abrasion with slurry = 28 (10-46). The calculated thickness of the softened enamel varied between 254 and 323 nm, depending on the acid used.

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Pneumococcal meningitis causes apoptosis of developing neurons in the dentate gyrus of the hippocampus. The death of these cells is accompanied with long-term learning and memory deficits in meningitis survivors. Here, we studied the role of the PI3K/Akt (protein kinase B) survival pathway in hippocampal apoptosis in a well-characterized infant rat model of pneumococcal meningitis. Meningitis was accompanied by a significant decrease of the PI3K product phosphatidylinositol 3,4,5-trisphosphate (PIP(3)) and of phosphorylated (i.e., activated) Akt in the hippocampus. At the cellular level, phosphorylated Akt was decreased in both the granular layer and the subgranular zone of the dentate gyrus, the region where the developing neurons undergo apoptosis. Protein levels and activity of PTEN, the major antagonist of PI3K, were unaltered by infection, suggesting that the observed decrease in PIP(3) and Akt phosphorylation is a result of decreased PI3K signaling. Treatment with the PTEN inhibitor bpV(pic) restored Akt activity and significantly attenuated hippocampal apoptosis. Co-treatment with the specific PI3K inhibitor LY294002 reversed the restoration of Akt activity and attenuation of hippocampal apoptosis, while it had no significant effect on these parameters on its own. These results indicate that the inhibitory effect of bpV(pic) on apoptosis was mediated by PI3K-dependent activation of Akt, strongly suggesting that bpV(pic) acted on PTEN. Treatment with bpV(pic) also partially inhibited the concentration of bacteria and cytokines in the CSF, but this effect was not reversed by LY294002, indicating that the effect of bpV(pic) on apoptosis was independent of its effect on CSF bacterial burden and cytokine levels. These results indicate that the PI3K/Akt pathway plays an important role in the death and survival of developing hippocampal neurons during the acute phase of pneumococcal meningitis.

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Measurement of bladder wall thickness (BWT) using transvaginal ultrasound has previously been shown to discriminate between women with confirmed detrusor overactivity and those with urodynamic stress incontinence. Aim of the current study was to determine if vaginally measured BWT correlates with urodynamic diagnoses in a female population.

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A laser scanning microscope collects information from a thin, focal plane and ignores out of focus information. During the past few years it has become the standard imaging method to characterise cellular morphology and structures in static as well as in living samples. Laser scanning microscopy combined with digital image restoration is an excellent tool for analysing the cellular cytoarchitecture, expression of specific proteins and interactions of various cell types, thus defining valid criteria for the optimisation of cell culture models. We have used this tool to establish and evaluate a three dimensional model of the human epithelial airway wall.

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EUS response assessment in patients with locally advanced esophageal cancer undergoing neoadjuvant chemoradiation therapy (CRT) is limited by disintegration of the involved anatomic structures.

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Introduction The objective of this study was to assess three-dimensional bone geometry and density at the epiphysis and shaft of the third meta-carpal bone of rheumatoid arthritis (RA) patients in comparison to healthy controls with the novel method of peripheral quantitative computed tomography (pQCT). Methods PQCT scans were performed in 50 female RA patients and 100 healthy female controls at the distal epiphyses and shafts of the third metacarpal bone, the radius and the tibia. Reproducibility was determined by coefficient of varia-tion. Bone densitometric and geometric parameters were compared between the two groups and correlated to disease characteristics. Results Reproducibility of different pQCT parameters was between 0.7% and 2.5%. RA patients had 12% to 19% lower trabecular bone mineral density (BMD) (P ≤ 0.001) at the distal epiphyses of radius, tibia and metacarpal bone. At the shafts of these bones RA patients had 7% to 16% thinner cortices (P ≤ 0.03). Total cross-sectional area (CSA) at the metacarpal bone shaft of pa-tients was larger (between 5% and 7%, P < 0.02), and relative cortical area was reduced by 13%. Erosiveness by Ratingen score correlated negatively with tra-becular and total BMD at the epiphyses and shaft cortical thickness of all measured bones (P < 0.04). Conclusions Reduced trabecular BMD and thinner cortices at peripheral bones, and a greater bone shaft diameter at the metacarpal bone suggest RA spe-cific bone alterations. The proposed pQCT protocol is reliable and allows measuring juxta-articular trabecular BMD and shaft geometry at the metacarpal bone.

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The use of self-expanding retrievable stents is an emerging and promising treatment strategy for acute stroke treatment. The concept combines the advantages of stent deployment with immediate flow-restoration and of mechanical thrombectomy with definitive thrombus removal. The present study was performed to gain more knowledge about the principle of combined flow restoration and thrombectomy in an established animal model using radiopaque thrombi evaluating efficiency, thrombus-device interaction and possible complications of the first dedicated flow-restoration and mechanical thrombectomy device.

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Measurement of bladder wall thickness using transvaginal ultrasound has previously been shown to discriminate between women with diagnosed detrusor overactivity and those with urodynamic stress incontinence. So far, no comparison has been made between abdominal, perineal and vaginal route for the measurement of bladder wall thickness. The aim of this prospective study was to determine if abdominal, perineal and vaginal ultrasound measurements of bladder wall thickness are comparable with each other.

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OBJECTIVE To determine the practicability and accuracy of central corneal thickness (CCT) measurements in living chicks utilizing a noncontact, high-speed optical low-coherence reflectometer (OLCR) mounted on a slit lamp. ANIMALS STUDIED Twelve male chicks (Gallus gallus domesticus). Procedures  Measurements of CCT were obtained in triplicate in 24 eyes of twelve 1-day-old anaesthetized chicks using OLCR. Every single measurement taken by OLCR consisted of the average result of 20 scans obtained within seconds. Additionally, corneal thickness was determined histologically after immersion fixation in Karnovsky's solution alone (20 eyes) or with a previous injection of the fixative into the anterior chamber before enucleation (4 eyes). RESULTS Central corneal thickness measurements using OLCR in 1-day-old living chicks provide a rapid and feasible examination technique. Mean CCT measured with OLCR (189.7 ± 3.34 μm) was significantly lower than histological measurements (242.1 ± 47.27 μm) in eyes with fixation in Karnovsky's solution (P = 0.0005). In eyes with additional injection of Karnovsky's fixative into the anterior chamber, mean histologically determined CCT was 195.2 ± 8.25 μm vs. 191.9 ± 8.90 μm with OLCR. A trend for a lower variance was found compared to the eyes that had only been immersion fixed. CONCLUSION Optical low-coherence reflectometry is an accurate examination technique to measure in vivo CCT in the eye of newborn chicks. The knowledge of the thickness of the chick cornea and the ability to obtain noninvasive, noncontact measurements of CCT in the living animal may be of interest for research and development of eye diseases in chick models.

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We aimed to evaluate whether carotid intima-media thickness (CIMT) or the presence of plaque can confer additional predictive value of future cardiovascular (CV) ischemic events in patients with pre-existing atherosclerotic vascular disease. We identified 2317 patients enrolled in the REduction of Atherothrombosis for Continued Health (REACH) registry who had atherosclerotic vascular disease and baseline CIMT measurements. The entire range of CIMT was divided into quartiles and the fourth quartile (? 1.5 mm) was defined as carotid plaque. Mean ± standard deviation baseline CIMT was 1.31 ± 0.65 mm. Associated CV ischemic events and vascular-related hospitalizations were evaluated over a 2-year follow-up. There was a positive increase in adjusted hazard ratios (HRs) for all-cause mortality (p = 0.04 for trend) and the quadruple endpoint (CV death, myocardial infarction (MI), stroke, hospitalization for CV events) with increasing quartiles of CIMT (p = 0.0008 for trend), which was mainly driven by the fourth quartile (carotid plaque). HRs for all-cause mortality, CV death, CV death/MI/stroke and the quadruple endpoint comparing the highest (carotid plaque) with the lowest CIMT quartile were 2.09 (95% CI, 1.07-4.10; p = 0.03); 2.49 (1.10-5.67; p = 0.03); 1.71 (1.10-2.67; p = 0.02); and 1.73 (1.31-2.27; p = 0.0001). In conclusion, our analyses suggest that the presence of carotid plaque, rather than the thickness of intima-media, appears to be associated with increased risk of CV morbidity and mortality, but confirmation of these findings in other population and prospective studies is required.

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The purpose of this retrospective radiographic study was to analyze the thickness of the facial bone wall at teeth in the anterior maxilla based on cone beam computed tomography (CBCT) images, since this anatomical structure is important for the selection of an appropriate treatment approach in patients undergoing postextraction implant placement. A total of 125 CBCT scans met the inclusion criteria, resulting in a sample size of 498 teeth. The thickness of the facial bone wall in the respective sagittal scans was measured perpendicular to the long axis of the tooth at two locations: at the crest level (4 mm apical to the cementoenamel junction; MP1) and at the middle of the root (MP2). No existing bone wall was found in 25.7% of all teeth at MP1 and in 10.0% at MP2. The majority of the examined teeth exhibited a thin facial bone wall (< 1 mm; 62.9% at MP1, 80.1% at MP2). A thick bone wall (? 1 mm) was found in only 11.4% of all examined teeth at MP1 and 9.8% at MP2. There was a statistically significant decrease in facial bone wall thickness from the first premolars to the central incisors. The facial bone wall in the crestal area of teeth in the anterior maxilla was either missing or thin in roughly 90.0% of patients. Both a missing and thin facial wall require simultaneous contour augmentation at implant placement because of the well-documented bone resorption that occurs at a thin facial bone wall following tooth extraction. Consequently, radiographic analysis of the facial bone wall using CBCT prior to extraction is recommended for selection of the appropriate treatment approach.

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The aim of this work is to assess the repeatability of spectral-domain-OCT (SD-OCT) retinal nerve fiber layer thickness (RNFL) thickness measurements in a non-glaucoma group and patients with glaucoma and to compare these results to conventional time-domain-OCT (TD-OCT).