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21.
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
22.
Reduction of creatine kinase and creatine kinase-MB indexes of infarct size by intravenous verapamil
In a prospective, controlled study, 29 patients were randomly allocated to receive intravenous verapamil, 5 to 10 mg/hour, for 2 days starting at a mean of 8 hours after the onset of myocardial infarction. Twenty-five patients received no specific treatment and served as control subjects. Left ventricular (LV) filling pressure in all patients was initially less than 15 mm Hg. Age, infarct localization and hemodynamic values on admission (Swan-Ganz catheter) were comparable in both groups. Maximal creatine kinase (CK) and creatine kinase-MB (CK-MB) values were markedly lower in the verapamil group than in the control group (CK 547 vs 703 U/liter, p less than 0.05; CK-MB 51 vs 68 U/liter, p less than 0.025), as was infarct weight (48 vs 65 g-Eq, p less than 0.03; CK-MB 31 vs 49 g-Eq, p less than 0.005). Arterial blood pressure was 10% lower in the verapamil group than in the control group. Systemic vascular resistance and LV filling pressure remained unchanged. Verapamil reduced myocardial infarction size by about 30% in patients without LV failure and the arterial pressure was reduced. 相似文献
23.
The effect of polypropylene mesh on ilioinguinal nerve in open mesh repair of groin hernia 总被引:7,自引:0,他引:7
Demirer S Kepenekci I Evirgen O Birsen O Tuzuner A Karahuseyinoglu S Ozban M Kuterdem E 《The Journal of surgical research》2006,131(2):175-181
OBJECTIVES: Repair of groin hernia is one of the most common operations performed by general surgeons, and mesh repair methods have gained wide acceptance. Chronic pain is the most serious long-term complication that can occur after repair of groin hernia. The development of chronic pain after herniorraphy has been attributed to several mechanisms, including damage to sensory nerves and mesh inguinodynia. MATERIAL AND METHODS: Twenty-four rabbits underwent bilateral inguinal dissection and synthetic polypropylene mesh laid on one side. Bilateral inguinal dissection was performed again after 3 months, and samples of nerve tissue were taken from both sides for histological examination. RESULTS: Light microscopic examination of the sections of control group peripheral nerves were in normal appearance, but the nerve fascicles in experimental group operated with mesh showed axonal dilation and mild-to-severe loss of myelinated axons. Examination of semi-thin and ultra-thin sections in control group peripheral nerve fascicles showed normal morphology. Ultrastructural nerve morphology in experimental group operated with mesh exhibited endoneurinal edema with thickening of both endoneurium and perineurium, causing separation of nerve fibers. Myelin sheaths of fibers showed an ondulation toward the axoplasm and the endoneurium. Separation of myelin layers from each other as a prominent feature of myelin degeneration in nerve fibers was also observed. Axoplasms exhibited edema and crystallization. CONCLUSIONS: The light microscopic and ultrastructural changes seen in peripheral nerves in experimental group operated with mesh suggested that mechanical compression of peripheral nerves is associated with myelin degeneration, endoneurinal and perineurial edema, fibrosis, axonal loss, and edema that may cause peripheral neuropathy. Chronic groin pain after hernia repair can be possibly caused by the entrapment of peripheral nerves in the scar tissue formed by the mesh. 相似文献
24.
Huseyin Eren Hasan Riza Aydin Levent Tumkaya Ilke Onur Kazaz Yildiray Kalkan Seher Nazli Kazaz 《Renal failure》2018,40(1):466-474
Purpose: This study investigated the antioxidant effects of whortleberry against cisplatin-induced nephrotoxicity in rats.Material and methods: This study included 48 female Sprague–Dawley rats weighing 263.68?±?8.29?g. The rats were divided into the following six groups, with eight rats in each group: control, ethanol control, whortleberry control, cisplatin control, 16?mg/kg cisplatin +100?mg/kg whortleberry, and 16?mg/kg cisplatin +200?mg/kg whortleberry groups. Biochemical analysis was performed by measuring total oxidant status and total antioxidant status, histopathological analysis was performed by calculating proximal and distal tubule areas (μm2), and immunohistochemical analysis was performed by determining anti-Caspase-3 immunostaining. Differences among the groups were examined using one-way analysis of variance, and p?.05 was considered statistically significant.Results: Cisplatin treatment decreased the total antioxidant status and increased the total oxidant status and Caspase-3 level. Moreover, it resulted in the dilatation, vacuolization and loss of tubular epithelial cells; and glomerular degeneration and edema in the kidney tissues (p?.05). Treatment with 100 and 200?mg whortleberries increased the total antioxidant status; decreased the total oxidant status and Caspase-3 level and ameliorated distal and proximal tubule degeneration, glomerular degeneration and edema in the kidney tissues (p?.05).Conclusions: Our results indicate that the antioxidant effects of the whortleberry decrease cisplatin-associated nephrotoxicity. 相似文献
25.
26.
Mirac Baris Usta Ozgur Korhan Tuncel Seher Akbas Berna Aydin Gokce Nur Say 《Nordic journal of psychiatry》2016,70(2):116-120
Background: Recent evidence shows that the hypothalamic–pituitary–adrenal (HPA) axis can be dysregulated in chronic sexual abuse victims with post-traumatic stress disorder (PTSD). We hypothesized that PTSD in adolescents exposed to a single sexual trauma may function as a chronic stressor leading to HPA-axis dysregulation. Aims: The objective of this study was to assess dehydroepiandrosterone sulphate (DHEA-S) and cortisol levels in female adolescents |with single sexual trauma-related PTSD compared to healthy controls. Method: We assessed 20 female adolescent (age 12–18) single sexual trauma victims with PTSD from the Ondokuz Mayis University Department of Child and Adolescent Psychiatry between December 2013 and December 2014. PTSD symptoms were assessed using the Child Depression Inventory (CDI) and Child Posttraumatic Stress Reaction Index (CPSRI). Blood cortisol and DHEA-S were measured in 20 female adolescent sexual abuse victims with PTSD and 20 healthy adolescents after 12-h fasting using the chemiluminescence method. Results: Compared to age-matched controls, female adolescent sexual abuse victims with PTSD had significantly lower DHEA-S levels (U = 70.00, Z = ? 3.517, p = 0.01, r = 0.55). There was also a significant negative correlation between DHEA-S and CDI scores (Spearman r = ? 0.522, p < 0.01). Conclusions: Decreased DHEA-S levels and correlation with depressive symptoms are evidence for a dysregulated HPA-axis in female adolescent single sexual trauma victims with PTSD. Further research is now recommended with large patient groups in order to maximize generalizations. 相似文献
27.
G?k?e Nur Say Bünyamin ?ahin Kerim Aslan Seher Akba? Lütfi ?ncesu Meltem Ceyhan 《Psychiatry investigation》2014,11(3):237-242
Objective
Thalamic abnormalities have been reported in people with pervasive developmental disorders (PDD) including Asperger''s Disorder (ASP). The aim of the present study was to compare the volume and volume fraction of the thalamus and the metabolite concentrations in children and adolescents with ASP using the magnetic resonance imaging and proton magnetic resonance spectroscopy. Additionally, the relationships between thalamic abnormalities and clinical features were examined.Methods
Volume and volume fractional and metabolic measurements of bilateral thalamus were collected from 15 boys with ASP with a total IQ over 70 (age range 7-18 years, mean age 11.6±3.79 years), and 15 healthy controls matching age, sex and IQ. The thalamic volumes, hemisphere volumes and total brain volumes (TBV) were estimated using the stereological methods on magnetic resonance images. Chemical metabolites of thalamus were evaluated by 1H spectroscopy.Results
No differences in thalamic volumes, volume fractions and metabolites were observed between the groups. There were significant correlation between thalamic volume and total brain volume in both groups. The ASP group showed a significant left-minus-right thalamus difference as well as a significantly greater laterality index. In addition, a significant correlation between the laterality index and Autism Behavior Checklist language scores was observed.Conclusion
Findings from this investigation point to a significant increase in laterality of the thalamus and a relationship with language problems in individuals with ASP. Our findings suggest that thalamic abnormalities may be related to mild language problems observed in ASP. 相似文献28.
Seher C Thierfelder W Dortschy R 《Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany))》2000,62(11):598-603
Within the framework of the German National Health interview and Examination Survey determinations of IgG-antibodies against the bacterium Helicobacter pylori in serum samples of study participants were conducted. The prevalence for the total population of Germany was 40%. No differences could be found between sexes. The comparison between study participants from the old and those from the new (territory of the former GDR) federal states of Germany did show that the prevalence rates were significantly higher in all age-groups of the eastern part (former GDR) of Germany. Possible causes and factors of influence are discussed. 相似文献
29.
We report the first known case of fulminant bone marrow necrosis (BMN) occurring after infusion of fluduabine monophosphate in a patient with recurrent low-grade non-Hodgkin's lymphoma (NHL). Extensive BMN is characterized by the development of fever, bony pain. a leukoerythroblastic peripheral blood film, variable degrees of pancytopenia and elevations in lactate dehydrogcnase and alkaline phosphatase. The diagnosis of BMN is rarely entertained ante-mortem. Although the precise role chemotherapy may have played in triggering fatal BMN remains speculative, we alert clinicians to be aware of this entity as more patients with indolent lymphomas and leukemias are treated with this and other potent nucleoside analogs. 相似文献
30.
Thierfelder W Bergmann KE Hellenbrand W Seher C Tischer A Thefeld W 《Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany))》2002,64(Z1):S23-S29
Laboratory tests will be performed as part of the National Health Survey for Children and Adolescents to identify health risks and to determine the seroprevalence of disease markers. The parameters were selected from haematology, clinical chemistry, allergology, endocrinology and serology of infectious diseases as indicators of individual health risks, to validate information collected by means of the questionnaires and to identify age specific immunity gaps of vaccine-preventable diseases. 相似文献