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Aydın Fatma Çakar Nilgün Kurt Tuba Çelikel Acar Banu Çelikel Elif Özçakar Zeynep Birsin Yalçınkaya Fatoş 《Clinical rheumatology》2022,41(12):3791-3796
Clinical Rheumatology - Intra-articular corticosteroid injection (IACI) is generally used in the management of juvenile idiopathic arthritis (JIA) to obtain rapid relief of active synovitis and... 相似文献
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PURPOSEWe aimed to evaluate the prostate volumes calculated as recommended in the PI-RADS v2 and PI-RADS v2.1 guidelines, intraobserver and interobserver variability, and the agreement between the two measurement methods.METHODSProstate mpMRI examinations of 114 patients were evaluated retrospectively. T2-weighted sequences in the axial and sagittal planes were used for the measurement of the prostate volume. The measurements were performed by two independent observers as recommended in the PI-RADS v2 and PI-RADS v2.1 guidelines. Both observers conducted the measurements twice and the average values were obtained. In order to prevent bias, the observers carried out measurements at one-week intervals. In order to assess intraobserver variability, observers repeated the measurements again at one-week intervals. The prostate volume was calculated using the ellipsoid formula (W×H×L×0.52).RESULTSIntraclass correlation coefficient (ICC) revealed almost perfect agreement between the first and second observers for the measurements according to both PI-RADS v2 (0.93) and PI-RADS v2.1 (0.96) guidelines. The measurements were repeated by both observers. According to the ICC values, there was excellent agreement between the first and second measurements with respect to both PI-RADS v2 and PI-RADS v2.1 for first (0.94 and 0.96, respectively) and second observer (0.94 and 0.97, respectively). For both observers, the differences had a random, homogeneous distribution, and there was no clear relationship between the differences and mean values.CONCLUSIONThe ellipsoid formula is a reliable method for rapid assessment of prostate volume, with excellent intra- and interobserver agreement and no need for expert training. For the height measurement, the recommendations of the PIRADS v2.1 guideline seem to provide more consistently reproducible results.The prostate gland is one of the organs for which the disease incidence and prevalence in men increases with age. Prostate volume (PV) has an important role in the evaluation and management of both malignant and benign prostate diseases (1–3). In benign prostatic hyperplasia (BPH), prostate volume is used to decide upon treatment and evaluate response to medical therapy (3–5). In the diagnosis of prostate cancer, one of the important markers is prostate-specific antigen (PSA), but it has low specificity, and therefore PSA derivatives are used to increase its specificity. One example is PSA density, which is obtained by dividing the PSA value by PV. In the treatment of prostate cancer, PV is important, and the effectiveness of brachytherapy decreases in prostates with a volume greater than 50 mL (6). Furthermore, PV is used to identify appropriate patients for brachytherapy and select the number of radioactive seeds, and also determine fractionation for external beam radiation, radical prostatectomy operating planning and continence rate counseling, and focal therapy candidacy preparation (7, 8). For these reasons, it is vital to accurately calculate PV.There are many methods that can be used to calculate PV, with the ellipsoid formula being one of the most preferred since it is easy to apply and highly time-efficient (1–4, 9). Many studies have shown that this method has high accuracy due to the elliptic shape of the prostate (1, 2, 10–13). The ellipsoid formula is obtained by multiplying the height (anterior-posterior), width (medio-lateral) and length (cranio-caudal) values of the prostate by 0.52. These measurements can be performed by transrectal ultrasonography (TRUS) or magnetic resonance imaging (MRI). TRUS has certain disadvantages, such as being operator-dependent and susceptible to sonographic artifacts (14). MRI, which has become increasingly popular in recent years, allows for an accurate definition of the prostate boundaries and multiplanar measurements through its high contrast resolution of soft tissues (1, 5). It also provides more accurate measurements than TRUS (4, 15, 16).In order to ensure global standardization in the reporting of prostate MRI findings, PI-RADS v2 published in 2015, which is the revised version of PI-RADS 1.0, and the last updated version PI-RADS v2.1 made available in 2019, propose different calculation methods for the measurement of height in obtaining PV (17, 18). The midaxial plane is recommended for this measurement in PI-RADS v2, while the midsagittal plane is recommended in PI-RADS v2.1. This study aimed to evaluate the interobserver and intraobserver variability of PV calculated by both measurement methods and the agreement between the two measurement methods. 相似文献
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Aye Erden Didem Kuru
z Elif Peker Melahat Kul Funda Seher
zalp Ate lhan Erden Ramazan dilman 《Diagnostic and interventional radiology (Ankara, Turkey)》2021,27(1):7
PURPOSENonalcoholic fatty liver disease (NAFLD) can progress to liver cirrhosis and is predicted to become the most frequent indication for liver transplantation in the near future. Noninvasive assessment of NAFLD is important for diagnosis and patient management. This study aims to prospectively determine the liver stiffness and T1 and T2 values in patients with NAFLD and to compare the diagnostic performance of magnetic resonance elastography (MRE) and mapping techniques in relation to the proton density fat fraction (PDFF).METHODSEighty-three patients with NAFLD and 26 participants with normal livers were imaged with a 1.5 T scanner. PDFF measurements obtained from the multiecho Dixon technique were used to quantify the liver fat. MRE, native T1 mapping (modified Look-Locker inversion recovery [MOLLI] schemes 5(3)3, 3(3)3(3)5, and 3(2)3(2)5 and the B1-corrected variable flip angle [VFA] method), and T2 mapping values were correlated with PDFF. The diagnostic performance of MRE and the mapping techniques were analyzed and compared.RESULTST1 values measured with the MOLLI schemes and the B1-corrected VFA (p < 0.001), and the stiffness values from MRE (p = 0.047) were significantly higher in the NAFLD group. No significant difference was found between the groups in terms of T2 values (p = 0.127). In differentiation of the NAFLD and control groups, the B1-corrected VFA technique had slightly higher accuracy and area under the curve (AUC) than the MOLLI schemes. In the NAFLD group, there was a good correlation between the PDFF, MOLLI 3(3)3(3)5 and 3(2)3(2)5, and VFA T1 measurements (r=0.732; r=0.735; r=0.716, p < 0.001, respectively).CONCLUSIONLiver T1 mapping techniques have the potential to distinguish steatotic from nonsteatotic livers, and T1 values seem to have a strong correlation with the liver fat content.Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease, with an estimated worldwide prevalence of around 25% (1). It may range from simple steatosis, which is considered a benign condition, to nonalcoholic steatohepatitis (NASH), which can progress to fibrosis, cirrhosis, liver failure, and hepatocellular carcinoma. NAFLD is also known to be associated with metabolic syndrome, which is a risk factor for cardiovascular disease and type II diabetes mellitus (2–4).The gold standard method for diagnosing NAFLD and distinguishing its different patterns is a liver biopsy which has considerable limitations, including sampling errors, its invasive nature and associated complication risks, small sample size, and inter- and intraobserver variability (5, 6). These drawbacks constrain its utility for clinical monitoring and make it unsuitable as a screening method. Therefore, there is an urgent clinical need for an accurate noninvasive approach in the assessment of NAFLD. Accordingly, both the European Association for the Study of the Liver and the American Association for the Study of Liver Disease propose magnetic resonance imaging (MRI) as a noninvasive diagnostic tool for NAFLD (7, 8). Proton density fat fraction (PDFF)-based MRI and magnetic resonance spectroscopy (MRS) techniques are considered the most accurate noninvasive methods for the quantification of liver fat (9–12). The PDFF is accepted as a standardized biomarker of hepatic steatosis. Studies suggest that this biomarker is equivalent to the hepatic “signal fat fraction” (FF) after correcting all the confounding factors (13). However, PDFF measurement is not suitable for the assessment of any inflammation or fibrosis in NAFLD (13). On the other hand, recent studies have shown that other quantitative MRI techniques such as magnetic resonance elastography (MRE) and T1–T2 mapping can be useful in detecting hepatic inflammatory and fibrotic changes (14, 15–21). Thus, the application of a multiparametric MRI protocol might be helpful in liver tissue characterization and thereby in the risk stratification and therapeutic management of patients with NAFLD.In this prospective study, we aimed to determine liver stiffness and T1 and T2 values in patients with NAFLD and nonsteatotic subjects and compare the diagnostic performance of MRE and mapping techniques in relation to the FF. 相似文献
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European Journal of Nuclear Medicine and Molecular Imaging - 相似文献
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Tülay Kamaak Beril Dilber Serap
zer Yaman Betül Diler Durgut Tuba Kurt Elif oban Elif Acar Arslan Sevim ahin Süleyman Caner Karahan Ali Cansu 《Epileptic Disord》2020,22(2):183-193
Aim: The purpose of this study was to compare HMGB‐1, TLR4, IL‐1β, IL‐1R1, and TNF‐α levels in patients with mild and severe epilepsy with those in a healthy control group. Methods: Children aged 4–17 years, diagnosed with epilepsy for at least three years and with no progressive neurological disease, metabolic disease or infection, were selected for the study. The severe epilepsy group consisted of 28 children with at least one episode a week despite receiving three or more antiepileptic drugs. The mild epilepsy group consisted of 29 children with no seizures in the previous year, receiving only one antiepileptic drug, while 27 healthy children were selected as the control group. HMGB‐1, TLR4, IL‐1R1, TNF‐α and IL‐1β levels were investigated in these three groups. The MRI findings and clinical characteristics of the patients in the epilepsy group were also compared with these markers. Results: HMGB‐1, TLR4, TNF‐α, and IL‐1β levels in the severe epilepsy group were higher than in the control group and the mild epilepsy group (p<0.05), and were higher in the mild epilepsy group than in the control group (p<0.05). IL‐1R1 was also higher in the severe epilepsy group than in the control group (p<0.05). Conclusion: In this first report to identity a possible correlation between HMGB‐1, TLR4, IL‐1β, IL‐1R1, and TNF‐α levels and severity of epilepsy, our data demonstrates that the serum level of these cytokines is higher in cases of drug‐refractory epilepsy. 相似文献
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Ercan Nain Ayca Kiykim Ismail Ogulur Nurhan Kasap Elif Karakoc‐Aydiner Ahmet Ozen Safa Baris 《Scandinavian journal of immunology》2019,90(5)
We evaluated 18 DiGeorge syndrome (DGS) patients and aimed to investigate the immunological changes in this population. DGS patients with low naive CD4+T and CD8+T cells were defined as high‐risk (HR) patients, whereas patients with normal numbers of naive CD4+ and CD8+T cells were defined as standard risk (SR) patients. Level of serum IgM, CD3+ T cell counts and percentages of class‐switched memory B cells were significantly low in HR group compared to SR ones. Severe infections and persistent hypoparathyroidism were detected significantly higher in HR group. Patients with reduced percentages of class‐switched B cells had earlier onset of infection, lower blood IgM, lower CD4+ and CD8+T counts than patients with normal class‐switched memory B cells. Decreased levels of IgM were associated with low numbers of naive CD4+ and recent thymic emigrants T cells. Monitoring the immune changes of patients with DGS would be useful to predict the severe phenotype of disease. 相似文献
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Ümmihan Taşkoparan Yilmaz Elif Calik Bayram Akdulum Hasim Yilmaz 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2018,26(1):300-308
A new, fast, sensitive and simple voltammetric method is established for the direct determination of carnosic acid (CA). And the electroreduction of carnosic acid (CA) was studied using electrochemical methods. The number of electrons transferred in electrode mechanisms were calculated for reversible and adsorption-controlled electrochemical reduction of CA at 17 mV versus Ag/AgCl at pH 7.0 in Britton–Robinson buffer (BR) on a hanging mercury drop electrode. Square-wave voltammetry was developed and validated for direct determination of CA. Square-wave parameters were optimized as accumulation potential = 0.0 mV, accumulation time = 5 s, frequency = 50 Hz, pulse amplitude = 50 mV, and staircase step potential = 5 mV. The developed method displays three linear responses from 2 to 9 μM, 10 to 30 and 40 to 90 μM for carnosic acid with a correlation coefficient of 0.996, 0.999 and 0.999. The detection limits were found to be 1.5 μM, 4.0 μM and 40.1 μM, respectively. The interference effect of most common organic and inorganic species was investigated. Proposed method was successfully applied for determination of CA in natural extract of rosemary and the average content was determined as 11.9 ± 1.0 (μg CA/1 g rosemary). The results were in agreement with that obtained by HPLC-UV comparison method. The developed method can be widely used in routine quality control of herbal materials as well as other in foods, medicinal, pharmaceutical and environmental analysis. 相似文献