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31.
Being the center of energy production in eukaryotic cells, mitochondria are also crucial for various cellular processes including intracellular Ca2+ signaling and generation of reactive oxygen species (ROS). Mitochondria contain their own circular DNA which encodes not only proteins, transfer RNA and ribosomal RNAs but also non-coding RNAs. The most recent line of evidence indicates the presence of 5-methylcytosine and 5-hydroxymethylcytosine in mitochondrial DNA (mtDNA); thus, the level of gene expression – in a way similar to nuclear DNA – can be regulated by direct epigenetic modifications. Up to now, very little data shows the possibility of epigenetic regulation of mtDNA. Mitochondria and mtDNA are particularly important in the nervous system and may participate in the initiation of drug addiction. In fact, some addictive drugs enhance ROS production and generate oxidative stress that in turn alters mitochondrial and nuclear gene expression. This review summarizes recent findings on mitochondrial function, mtDNA copy number and epigenetics in drug addiction. 相似文献
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Simon Nicolay Luc De Beuckeleer Daniël Stoffelen Filip Vanhoenacker Marc Pouillon 《Skeletal radiology》2014,43(5):699-702
We report an 89-year-old woman with bilateral atraumatic scapular spine fracture several months after bilateral reverse total shoulder arthroplasty (RTSA). Recently, RTSA has gained popularity in the surgical treatment of complex shoulder disorders such as cuff tear arthropathy. However, scapular fractures may occur several months after surgery as a late complication of this procedure. In this case report we focus on a relatively uncommon subtype, the scapular spine fracture. Although well-known in the orthopedic literature, radiologists are less familiar with this complication. To the best of our knowledge, bilateral scapular fractures have not yet been reported. 相似文献
34.
Eamonn Ferguson Filip Lievens 《Advances in health sciences education : theory and practice》2017,22(2):387-399
This paper has two objectives: (1) presenting recent advances in personality theory whereby personality traits are conceptualized within a framework that focuses on the dynamic interactions of behaviour, biology, context, and states, and (2) discussing the implications of these developments for measurement and medical selection. We start by presenting evidence that traits are no longer regarded as stable deterministic predictors of behaviour. Instead, traits are found to change across generations, the life span, and in response to environmental contingencies. Thus, there is an urgent need to explore how traits change as function of medical education. Second, drawing on recent theory and research (behavioural reaction norms and the density distribution model) we highlight evidence to show how the expression of trait relevant behaviour is dependent on context, and is distributed with an average (typical behaviour or personality) and a variance (plasticity or adaptability), with traditional personality measure associated with typical responding. Third, we demystify that some traits are better than others showing that so-called “good” traits have a dark-side. Fourth, we show how these developments impact on how personality might be assessed, thereby presenting recent evidence on the use of contextualized personality measures, situational judgment tests, other reports, and implicit measures. Throughout the paper, we outline the key implications of these developments for medical selection practices. 相似文献
35.
Budesonide in collagenous colitis: a double-blind placebo-controlled trial with histologic follow-up. 总被引:7,自引:0,他引:7
Filip Baert Alain Schmit Geert D'Haens Franceska Dedeurwaerdere Edouard Louis Marc Cabooter Martine De Vos Fernand Fontaine Serge Naegels Piet Schurmans Hedwig Stals Karel Geboes Paul Rutgeerts 《Gastroenterology》2002,122(1):20-25
BACKGROUND & AIMS: Collagenous colitis (CC) is a well-described entity causing chronic diarrhea and characteristic histologic findings. Several treatment options have been suggested, but no controlled data are available. We conducted a placebo-controlled trial to show the clinical and histologic effects of budesonide in CC. METHODS: Twenty-eight patients were randomly assigned to receive placebo (n = 14) or budesonide 9 mg daily (n = 14) for 8 weeks. Patients were evaluated clinically, and blinded biopsy specimens were analyzed from fixed locations at weeks 0 and 8. Clinical response was defined as a decrease of at least 50% in the disease activity score (number of bowel movements in the last 7 days). At week 8, nonresponders received open-label budesonide for the next 8-week period; responders discontinued treatment and were followed up. RESULTS: Three patients discontinued the study prematurely. Intention-to-treat analysis showed clinical response in 8 of 14 patients in the budesonide group compared with 3 of 14 responders for placebo (P = 0.05) after 8 weeks of blinded therapy, together with improved stool consistency. Histologically, there was no change in the mean thickness of the collagen band but a significant decrease of the lamina propria infiltrate in the budesonide group (P < 0.001). CONCLUSIONS: Budesonide is efficacious in inducing short-term clinical response in CC with significant reduction of the histologic infiltrate in the lamina propria. 相似文献
36.
De Rycke L Baeten D Kruithof E Van den Bosch F Veys EM De Keyser F 《Arthritis and rheumatism》2005,52(7):2192-2201
OBJECTIVE: To analyze the clinical and biologic correlates of autoantibody induction during longer-term tumor necrosis factor alpha (TNFalpha) blockade with either the monoclonal antibody infliximab or the soluble receptor etanercept. METHODS: Thirty-four patients with spondylarthropathy (SpA) and 59 patients with rheumatoid arthritis (RA) were treated with infliximab for 2 years. Additionally, 20 patients with SpA were treated with etanercept for 1 year. Sera were blindly analyzed for antinuclear antibodies (ANAs), anti-double-stranded DNA (anti-dsDNA) antibodies, anti-extractable nuclear antigen (anti-ENA) antibodies, and antihistone, anti-nucleosome, and anticardiolipin antibodies (aCL). The anti-dsDNA antibodies were isotyped. RESULTS: High numbers of infliximab-treated patients with SpA or RA had newly induced ANAs (61.8% and 40.7%, respectively) and anti-dsDNA antibodies (70.6% and 49.2%, respectively) after 1 year, but no further increase between year 1 and year 2 was observed. In contrast, induction of ANAs and anti-dsDNA antibodies was observed only occasionally in the etanercept-treated patients with SpA (10% of patients each). Isotyping revealed almost exclusively IgM or IgM/IgA anti-dsDNA antibodies, which disappeared upon interruption of treatment. Neither infliximab nor etanercept induced other lupus-related reactivities such as anti-ENA antibodies, antihistone antibodies, or anti-nucleosome antibodies, and no clinically relevant lupus-like symptoms were observed. Similarly, infliximab but not etanercept selectively increased IgM but not IgG aCL titers. CONCLUSION: The prominent ANA and anti-dsDNA autoantibody response is not a pure class effect of TNFalpha blockers, is largely restricted to short-term IgM responses, and is not associated with other serologic or clinical signs of lupus. Similar findings with aCL suggest that modulation of humoral immunity may be a more general feature of infliximab treatment. 相似文献
37.
Bart Dingenen Louis Peeraer Kevin Deschamps Steffen Fieuws Luc Janssens Filip Staes 《Journal of Athletic Training》2015,50(7):688-696
Context
Participants with chronic ankle instability (CAI) use an altered neuromuscular strategy to shift weight from double-legged to single-legged stance. Shoes and foot orthoses may influence these muscle-activation patterns.Objective
To evaluate the influence of shoes and foot orthoses on onset times of lower extremity muscle activity in participants with CAI during the transition from double-legged to single-legged stance.Design
Cross-sectional study.Setting
Musculoskeletal laboratory.Patients or Other Participants
A total of 15 people (9 men, 6 women; age = 21.8 ± 3.0 years, height = 177.7 ± 9.6 cm, mass = 72.0 ± 14.6 kg) who had CAI and wore foot orthoses were recruited.Intervention(s)
A transition task from double-legged to single-legged stance was performed with eyes open and with eyes closed. Both limbs were tested in 4 experimental conditions: (1) barefoot (BF), (2) shoes only, (3) shoes with standard foot orthoses, and (4) shoes with custom foot orthoses (SCFO).Main Outcome Measure(s)
The onset of activity of 9 lower extremity muscles was recorded using surface electromyography and a single force plate.Results
Based on a full-factorial (condition, region, limb, vision) linear model for repeated measures, we found a condition effect (F3,91.8 = 9.39, P < .001). Differences among experimental conditions did not depend on limb or vision condition. Based on a 2-way (condition, muscle) linear model within each region (ankle, knee, hip), earlier muscle-activation onset times were observed in the SCFO than in the BF condition for the peroneus longus (P < .001), tibialis anterior (P = .003), vastus medialis obliquus (P = .04), and vastus lateralis (P = .005). Furthermore, the peroneus longus was activated earlier in the shoes-only (P = .02) and shoes-with-standard-foot-orthoses (P = .03) conditions than in the BF condition. No differences were observed for the hip muscles.Conclusions
Earlier onset of muscle activity was most apparent in the SCFO condition for ankle and knee muscles but not for hip muscles during the transition from double-legged to single-legged stance. These findings might help clinicians understand how shoes and foot orthoses can influence neuromuscular control in participants with CAI.Key Words: footwear, insoles, ankle sprains, neuromuscular system, electromyographyKey Points
- Shoes and foot orthoses accelerated muscle-activation onset times of the ankle and knee but not the hip in participants with chronic ankle instability.
- Earlier muscle-activation onset times were most prominent in the shoes-with-custom-foot-orthoses condition.
- At the ankle, the muscle-activation onset time of the peroneus longus was earlier in the shoes-only, shoes-with-standard-foot-orthoses, and shoes-with-custom-foot-orthoses conditions than in the barefoot condition, and the muscle-activation onset time of the tibialis anterior was earlier in the shoes-with-custom-foot-orthoses condition than in the barefoot condition.
- At the knee, the muscle-activation onset times of the vastus medialis obliquus and vastus lateralis were earlier in the shoes-with-custom-foot-orthoses condition than in the barefoot condition.
- The results may help clinicians understand how shoes and foot orthoses can influence neuromuscular control of the lower extremity in participants with chronic ankle instability.
38.
Avan Suinesiaputra Mihir M. Sanghvi Nay Aung Jose Miguel Paiva Filip Zemrak Kenneth Fung Elena Lukaschuk Aaron M. Lee Valentina Carapella Young Jin Kim Jane Francis Stefan K. Piechnik Stefan Neubauer Andreas Greiser Marie-Pierre Jolly Carmel Hayes Alistair A. Young Steffen E. Petersen 《The international journal of cardiovascular imaging》2018,34(2):281-291
UK Biobank, a large cohort study, plans to acquire 100,000 cardiac MRI studies by 2020. Although fully-automated left ventricular (LV) analysis was performed in the original acquisition, this was not designed for unsupervised incorporation into epidemiological studies. We sought to evaluate automated LV mass and volume (Siemens syngo InlineVF versions D13A and E11C), against manual analysis in a substantial sub-cohort of UK Biobank participants. Eight readers from two centers, trained to give consistent results, manually analyzed 4874 UK Biobank cases for LV end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and LV mass (LVM). Agreement between manual and InlineVF automated analyses were evaluated using Bland–Altman analysis and the intra-class correlation coefficient (ICC). Tenfold cross-validation was used to establish a linear regression calibration between manual and InlineVF results. InlineVF D13A returned results in 4423 cases, whereas InlineVF E11C returned results in 4775 cases and also reported LVM. Rapid visual assessment of the E11C results found 178 cases (3.7%) with grossly misplaced contours or landmarks. In the remaining 4597 cases, LV function showed good agreement: ESV ?6.4?±?9.0 ml, 0.853 (mean?±?SD of the differences, ICC) EDV ?3.0?±?11.6 ml, 0.937; SV 3.4?±?9.8 ml, 0.855; and EF 3.5?±?5.1%, 0.586. Although LV mass was consistently overestimated (29.9?±?17.0 g, 0.534) due to larger epicardial contours on all slices, linear regression could be used to correct the bias and improve accuracy. Automated InlineVF results can be used for case-control studies in UK Biobank, provided visual quality control and linear bias correction are performed. Improvements between InlineVF D13A and InlineVF E11C show the field is rapidly advancing, with further improvements expected in the near future. 相似文献
39.