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61.
Canbaz F Basoglu T Durna K Semirgin SU Canbaz S 《The international journal of cardiovascular imaging》2008,24(6):585-596
PURPOSE: The objective of this trial was to investigate the capacity of gated perfusion SPECT (GPS) to detect left ventricular aneurysm (ANV) by comparing QGS and 4D-MSPECT (4DM) algorithms with radionuclide ventriculography (RVG). Secondarily, the comparison of GPS ejection fraction (EF) measurements with those of contrast left ventriculography (LVG) and RVG was aimed. METHODS: Twenty-five patients with ANV confirmed by LVG were studied. The patients underwent RVG and rest Tc-99m-tetrofosmin GPS 1 week after LVG. A 9-segment model was used both in RVG and GPS evaluation. Aneurysm was defined by scoring the wall motion (WM) and phase analysis in RVG; perfusion, wall thickening and WM in GPS. RESULTS: The detection rate of ANV was 96%, 84% and 52% for RVG, QGS and 4DM, respectively. The LVG mean EF (43.52% +/- 16.93%) was significantly higher (P < 0.01) than those of RVG (29.40% +/- 10.90), QGS (30.04% +/- 13.25%) and 4DM (34.92% +/- 13.01%). Moderate to high EF correlation values were obtained between LVG and GPS (r = 0.71-0.79) and GPS-RVG (r = 0.69). There was no significant EF difference between the radionuclide methods except between 4DM-EF and RVG-EF (5.52%, P < 0.05). Wide Bland-Altman limits were observed between the radionuclide methods in EF comparisons (range: 30.5-38.5%). CONCLUSION: GPS seems to have a role in the non-invasive investigation of ANV. QGS-GPS proved to be more reliable (84%) than 4DM-GPS (52%) in the ANV detection. The localization and the extent of the aneurysm itself as well as perfusion and function of adjacent segments may affect aneurysm diagnosis by means of GPS. RVG, QGS-GPS and 4DM-GPS seem not to be interchangeable for routine EF calculation in ANV patients. 相似文献
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Abstract: Acquired partial lipodystrophy is an extremely rare condition of unknown etiology characterized by progressive loss of fat of the face, neck, trunk, and upper extremities. It usually begins during childhood and is more common in girls. C3 hypocomplementemia is seen in 70% of patients with acquired partial lipodystrophy. Unlike generalized forms of the disease, no insulin resistance occurs. We present three boys with acquired partial lipodystrophy having C3 hypocomplementemia. In addition, one of them had antiphospholipid and anticardiolipin antibodies. 相似文献
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Sevgi Akarsu Turna İlknur Emel Fetil Banu Lebe Ali Tahsin Güneş 《Photodermatology, photoimmunology & photomedicine》2010,26(2):101-103
We report on a 35‐year‐old woman with cutaneous lesions characterized by an erythema multiforme‐like appearance localized in the photo‐distributed pattern. She had no history of systemic drug ingestion, herpes simplex virus or any other infection, possible causes of erythema multiforme, before the sun exposure. She had normal tolerance to a phototest, but photoprovocation tests could not be performed because she did not agree to them. This case was diagnosed to be an erythema multiforme‐like variant of a polymorphous light eruption; the differential diagnosis of target‐like lesions in a photo‐distributed pattern is discussed. 相似文献
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Dimethyl‐ and monomethylfumarate regulate indoleamine 2,3‐dioxygenase (IDO) activity in human immune cells 下载免费PDF全文
Sevgi Eminel Na Jin Martin Rostami Stefan Dibbert Ulrich Mrowietz Ina Suhrkamp 《Experimental dermatology》2017,26(8):685-690
Fumaric acid esters (FAEs) are used as an oral treatment for psoriasis. Dimethylfumarate (DMF) and its metabolite monomethylfumarate (MMF) are regarded as the pharmacologically active moieties. Indoleamine 2,3‐dioxygenase (IDO) is the key enzyme for the metabolism of tryptophan. The kynurenine pathway is established as a major regulator of innate and adaptive immunity. Here, we investigated the effect of DMF and MMF on IDO activity and expression in human peripheral blood mononuclear cells (PBMCs). IDO activity was determined by measuring the concentration of kynurenine in the culture medium using a HPLC technique. IDO and kynureninase protein expressions were analysed by Western blot. Our results demonstrated that DMF and MMF dose‐dependently reduced the levels of L‐kynurenine in PBMCs activated by interferon‐γ (IFN‐γ). Furthermore, MMF had an inhibitory effect on IDO activity in vitro with an ED50 of 10 μmol/L, a value within the therapeutic concentration range for this molecule. We also observed that IDO and kynureninase expressions were reduced in PBMCs in a dose‐dependent manner by DMF and MMF. The results of our study show that DMF and MMF (in therapeutic concentrations) inhibited IDO and kynureninase activity and expression in a NF‐κB‐dependent manner in PBMCs while also decreasing the level of L‐kynurenine in these cells. As we found that FAEs inhibit both IDO expression and enzymatic activity leading to a modulation of tryptophan degradation, we believe this effect may contribute to the clinical efficacy of this drug in psoriasis by downregulating pro‐inflammatory mediators generated by the kynurenine pathway. 相似文献
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Gaute Floer Johnsen Hvard Haugen J Liebert Parreiras Nogueira Usame Sevgi Ashley Mae Jimenez Joseph T. DeLuca Ryan Mancuso Lucila Piasecki 《International dental journal》2023,73(1):71-78
IntroductionThe purpose of this study was to determine the degree of similarity between contralateral mandibular incisors utilising 3-dimensional (3D) models obtained from micro-computed tomographic (micro-CT) scans of extracted human teeth. The null hypothesis was that contralateral mandibular incisors do not exhibit matching symmetry.MethodsSixty pairs (n = 120) of extracted mandibular incisors were obtained from 30 patients and scanned with micro-CT with a voxel size of 15.0 μm. 3D virtual models of the pulpal cavities were rendered. Geometric morphometric deviation analysis was performed after mirroring, automatic alignment, and co-registration of the models of contralateral teeth root mean square (RMS) errors were calculated. The quantitative analysis of the 3D models included 6 different geometric parameters. Data sets were examined with a 2-sample Kolmogorov–Smirnov test. Post hoc retrospective power analysis was performed to find statistical power (α = 0.05).ResultsContralateral pairs had a narrower distribution in deviation than random pairs. Also, contralateral pairs showed a statistically higher similarity coefficient (5 out of 6 geometric parameters) compared to random pairs (P < .001); no difference was found when comparing central to lateral pairs or between Vertucci type I configurations compared to non-type I. RMS errors had significantly lower Contralateral premolars (CPs) values than random pairs (P < .001).ConclusionsA high degree of similarity was demonstrated for pairing contralateral mandibular incisors using 3D models. The similarity between contralateral central and lateral incisors suggests that when screened and matched, these 4 teeth might be used in endodontic research where similar root canal anatomy is crucial. 相似文献
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B. Baran M. Gulluoglu O. M. Soyer A. C. Ormeci S. Gokturk S. Evirgen S. Yesil F. Akyuz C. Karaca K. Demir S. Kaymakoglu F. Besisik 《Journal of viral hepatitis》2014,21(2):111-120
Chronic hepatitis C (CHC) patients with treatment failure (TF) remain at risk of continuing fibrosis progression. However, it has not been investigated whether there is an increased risk of accelerated fibrosis progression after failed interferon‐based therapy. We aimed to investigate long‐term influence of TF on fibrosis progression compared with untreated patients with CHC. We studied 125 patients with CHC who underwent paired liver biopsies from 1994 to 2012. Patients with advanced fibrosis were excluded from the analysis. Sixty‐three patients had TF, and 62 patients were treatment‐naïve (TN). Annual fibrosis progression rate (FPR) was calculated, and significant fibrosis progression (SFP) was defined as ≥2 stage increase in fibrosis during follow‐up. Multiple regression analyses were performed to find out independent predictors of FPR and SFP. Demographic characteristics and duration between paired liver biopsies were similar in TF and TN groups. Baseline alanine aminotransferase and gamma‐glutamyl transferase (GGT) levels (71 ± 31 vs 47 ± 22, P < 0.001 and 49 ± 39 vs 36 ± 28, P = 0.027, respectively), baseline mean fibrosis stage (2.2 ± 0.7 vs 1.9 ± 0.7, P = 0.018) and histologic activity index (6.3 ± 1.9 vs 4.3 ± 1.6, P < 0.001) were higher in the TF group compared with the TN group. In regression analyses, the strongest independent predictor of fibrosis progression was the GGT level (OR: 1.03, 95%CI 1.01–1.5, P < 0.001). Treatment experience (OR: 5.97, 95%CI 1.81–19.7, P = 0.003) also appeared as an independent predictor of both FPR and SFP. Failed interferon‐based CHC treatment may lead to accelerated FPR in the long‐term compared with the natural course. 相似文献
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Several recent studies demonstrated beneficial effects of G-CSF treatment (granulocyte colony-stimulating factor) in various CNS disease. Possible mechanisms underlying this activity are neuroprotection, anti-apoptosis, angiogenesis and anti-inflammation. Hence, we investigated the efficacy of G-CSF administration in experimental stroke by determining infarct volume and neurological score in wildtype, G-CSF-deficient and G-CSF-treated G-CSF-deficient mice. Besides, cerebral ischemia is followed by an upregulation of endothelial adhesion molecules which promote leukocyte recruitment to the injured area. In combination with G-CSF-induced leukocytosis, increased peripheral neutrophils could aggregate within microvasculature and additionally impair blood perfusion of the ischemic tissue. Therefore, we analyzed the neutrophil counts in both vessel and tissue compartment 2 and 5 days post-stroke by immunohistochemistry.Here we show that G-CSF deficiency leads to increased infarct volumes, whereas G-CSF substitution revokes detrimental effects by reducing lesion size and enhancing neurological outcome compared to untreated animals. Administration of G-CSF is accompanied by significant increase of circulating neutrophils 2 days post-ischemia but leukocytosis is restricted to the vessel compartment and has no deleterious effect on lesion formation and functional recovery. These observations are likely to be important for therapeutic targeting of G-CSF-mediated neuroprotection in stroke. 相似文献