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Eleftherios Lavdas Marianna Vlychou Nikolaos Arikidis Eftychia Kapsalaki Violeta Roka Dimitrios L. Arvanitis Ioannis Fezoulidis Katerina Vassiou 《Clinical imaging》2013,37(4):697-703
PurposeThe purpose of the present study was to evaluate the visibility and the image quality of the biliary and pancreatic duct system on magnetic resonance cholangiopancreatography (MRCP) images based on two breath-hold (BH) methods using array spatial sensitivity technique: a single-shot fast spin-echo (SS-FSE) sequence and a three-dimensional single slab fast spin-echo (3D-FSE) sequence.Materials and methodsIn the present prospective comparative study, 47 patients (22 male and 25 female, mean age=50 years, age range=22–82 years) that were referred for MRCP during a 12-month period are included. All of them were referred with suspected pancreaticobiliary disease. All patients underwent MRCP with both a SS-FSE BH sequence and a 3D-FSE BH sequence. Qualitative evaluation regarding the depiction of three segments of the pancreaticobiliary tree and the frequency of artifacts was performed. Two radiologists graded each sequence of the obtained studies in a blinded fashion. Quantitative evaluation including calculation of relative signal intensity (rSI) and relative contrast (RC) ratios at seven segments of the pancreaticobiliary tree between fluid-filled ductal structures and organ parenchyma at the same ductal segments was performed. In order to evaluate the parameters' differences of the two sequences, either in qualitative or in quantitative analysis, the Wilcoxon paired signed-rank test was performed.ResultsOn quantitative evaluation, both rSI and RC ratios of all segments of the pancreaticobiliary tree at SS-FSE BH sequence were higher than those at 3D-FSE BH sequences. This finding was statistically significant (P< .01). On qualitative evaluation, the two radiologists found intrahepatic ducts and pancreatic ducts to be better visualized with SS-FSE BH than with 3D-FSE BH sequence. This finding was statistically significant (P< .02). One of them found extrahepatic ducts to be significantly better visualized with SS-FSE BH sequence. Moreover, the frequency of artifacts was lower in the SS-FSE sequence, a finding that was of statistical significance. Interobserver agreement analysis found at least substantial agreement (κ>0.60) between the two radiologists.ConclusionThe SS-FSE sequence is performed faster and significantly improves image quality; thus, it should be included into the routine MRCP sequence protocol at 3.0 T. Furthermore, we recommended SS-FSE BH MRCP examination to be applied to uncooperative patients or patients in emergency because of its short acquisition time (1 s). 相似文献
23.
Leonidas D. Arvanitis MD Paolo Gattuso MD Sukriti Nag MD 《Brain pathology (Zurich, Switzerland)》2013,23(3):359-360
Combined tumors showing histologic features of both ependymoma and subependymoma have been described. In this report we present a case of combined tanycytic ependymoma with foci of subependymoma (WHO grade II), occurring in a 40 year‐old male, which arose in the wall of the lateral ventricle. The tanycytic ependymoma component showed elongated fibrillary cells with a fascicular pattern of growth, while the subependymoma component showed clustered cell bodies surrounded by a fibrillary stroma with a microcystic appearance. We consider the present case to be an unusual example of tanycytic ependymoma; which to the best of our knowledge has not been associated with a subependymoma. 相似文献
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Nicole B. Jacobson RD LD CNSD Neha Parekh MS RD LD CNSD Matt Kalaycio MD 《Current hematologic malignancy reports》2006,1(3):188-194
Patients with acute leukemia who undergo hematopoietic stem cell transplantation (HSCT) are susceptible to malnutrition caused
by several factors including intensive cytotoxic therapy. This paper discusses the significance of malnutrition in these patients
and provides an overview of nutrition therapy by the oral, enteral, and parenteral routes. The goal is to investigate whether
the use of parenteral nutrition (PN) produces improved clinical outcomes in patients with acute leukemia and to identify criteria
for the selection of patients most likely to benefit from this therapy. Although PN may be appropriate for patients suffering
from complications such as graft-versus-host disease (GVHD) and mucositis, the data available at this time do not support
PN as first-line therapy for all recipients of HSCT. 相似文献
26.
Sotiriou S Liatsos K Ladopoulos I Arvanitis DL 《Clinical and experimental obstetrics & gynecology》2004,31(3):185-190
PURPOSE: To investigate the role of heat shock protein (HSP) on the chorionic villi of human placental cells and to compare the concentration of placental HSP70 & 90 in term deliveries and in missed miscarriages. MATERIALS AND METHODS: Fifty products of conception from women who experienced first trimester missed miscarriage and 50 placentas from women who gave birth at term were studied. An immunohistochemical investigation was carried out with which we marked the localization of heat shock proteins 70 and 90 on the syncytiotrophoblastic, cytotrophoblastic, stromal and blood vessel cells, using specific antibodies which can detect the presence of those proteins on light microscopy. We compared their expression with the normal placental tissue of term pregnancies and with material acquired from first trimester missed miscarriages. An indirect immunoperoxidase method was applied using polyclonal antibodies against HSP70 and HSP90 on formalin-fixed paraffin-embedded tissues. RESULTS: Expression of HSP90B was increased in chorionic villi of first trimester missed miscarriages concerning syncytiotrophoblasts, cytotrophoblasts, vessel and stroma cells compared to full-term placentas. There was a statistically significant increase of HSP90A expression in chorionic villi of first trimester missed miscarriages, concerning only the cytotrophoblast cells, compared to full-term placentas. Expression of HSP70 cognate protein was significantly increased in chorionic villi of first trimester missed miscarriages, concerning syncytiotrophoblastic cells only, compared to full-term placentas. Finally, HSP70 inducible protein was significantly increased in chorionic villi of first trimester missed miscarriages concerning syncytiotrophoblasts, cytotrophoblasts, vessel and stroma cells compared to full-term placentas. CONCLUSIONS: The results of the present study have sufficiently shown that there is an increase of HSP70 & 90 expression in chorionic villi of first trimester missed miscarriages compared to full-term placentas and this increase may have an important implication on the miscarriage process. 相似文献
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28.
Arvanitis DA Papadakis E Zafiropoulos A Spandidos DA 《Lung cancer (Amsterdam, Netherlands)》2003,40(1):55-66
Using PCR-based microsatellite DNA analysis with 48 markers we examined sputum and bronchial washing for genetic alterations compared with lymphocyte extracted DNA from 124 lung cancer patients and 36 healthy donors as normal control. Microsatellite alterations (MA) in at least one locus were detected in all cancer patient-derived specimens but only in 22.2% of the healthy donors. Loss of heterozygosity (LOH) was detected in bronchial washings from 101 non-small cell lung cancer (NSCLC) predominantly on 17p13.1-p13.3 (69.7%), 9p13.3-p24.1 (63.3%), 1p34.2-p36.22 (48.5%), 13q12.1-q13.1 (47.7%) and 3p22.3-p23 (42.7%). In bronchial washings from 23 small cell lung cancer (SCLC) LOH was detected mostly on 3p22.3-p23 (88.6%), 17p13.1-p13.2 (82.3%), 5q32-q33.1 (66.6%), 13q12.2-q13.1 (65.6%) and 9q22.33-q31.3 (52.9%). The different LOH patterns indicate that different genetic background may be responsible for the different physiology of NSCLC and SCLC. The fractional allele loss (FAL) mean value of all cancer specimens was 0.243+/-0.021 compared with 0.007+/-0.008 of healthy donors with a confidence interval (CI) 99.5%. Only seven out of 124 lung cancer specimens (5.2%) exhibited FAL value less than 0.083, the highest was observed in the healthy donors group. FAL appears to be a likely indicator for lung cancer detection. Microsatellite instability (MIN) was detected in 8.7% of SCLC and 4.0% of NSCLC bronchial washings in at least three loci tested. LOH and MIN detection in sputum and bronchial washing from the same patient was 77.6%. Calculation of these indexes per marker exhibits significant variations that could be attributed to diffuse lung disorders or non-cancer specific genetic alterations. 相似文献
29.
Vrentzos GE Papadakis JA Vardakis KE Maliaraki N Stilianou K Arvanitis A Sratigis S Alivanis P Margioris AN Ganotakis ES 《Journal of nephrology》2003,16(4):535-539
BACKGROUND: High serum levels of total homocysteine (tHcy) are common in dialysis patients with end-stage renal disease (ESRD). We assumed that these patients may have decreased response to conventional folic acid (FOL) and vitamin B12 (B12) administered orally. This study aimed to evaluate the efficacy of an intravenous (i.v.) B12 regimen in ESRD patients and compare it with the conventional regimen. METHODS: We designed an open label, crossover, non-randomized study of 72 ESRD patients. Our patients were hemodialyzed in two hospitals (HOSP1 and HOSP2). In HOSP1, patients were on 1 mg of FOL and 600 micog of B12 orally for 3 months, and then switching to 1 mg of B12 i.v. for 3 additional months, while the FOL dosage was constant. In HOSP2, patients received the same treatment in reverse. RESULTS: Patients in HOSP1 (n = 37) after i.v. B12 treatment, had significantly lower tHcy (p < 0.001) and FOL (p < 0.05) serum levels, compared with those at the end of oral B12 treatment. On the contrary in HOSP2 patients, serum tHcy levels increased significantly (n = 35, p < 0.0001) when i.v. was switched to oral treatment. There was a significant inverse correlation between tHcy and B12 (p < 0.0001) at the end of the i.v. treatment period; while treatment there was no correlation between tHcy and FOL serum levels. At the end of the oral treatment period, there was no significant correlation between tHcy and B12 serum levels, while tHcy and FOL serum levels had a significant inverse correlation (p = 0.002). CONCLUSIONS: Our results suggest that ESRD patients on dialysis have 'B12 resistance', and that they should have, in addition to their FOL therapeutic regimen, i.v. B12 treatment to reduce their elevated tHcy levels. 相似文献
30.
Issidorides MR Havaki S Chrysanthou-Piterou M Arvanitis DL 《Ultrastructural pathology》2000,24(6):399-405
A temporal lobe ganglioglioma, surgically removed from an 8-year-old body, and a human brainstem at the level of locus coeruleus (LC) were processed for light microscopy (LM), with formalin fixation and paraffin embedding, and for electron microscopy (EM) with glutaraldehyde fixation, potassium permanganate postfixation, phosphotungstic acid-hematoxylin block-staining, and epoxy-resin embedding. The paraffin sections were stained with toluidine blue O/rhodamine B and observed under epi-fluorescence. The thin sections for EM were viewed directly without further staining. The neuronal neoplastic cells of ganglioglioma and the neurons of LC are known to produce catecholamines. Both also contain spherical protein bodies (pb), cellular markers that identify catecholamine neurons in humans. The ultrastructural characteristics of the pb in LC were compared with those of the pb in neoplastic ganglion cells. These bodies had an identical ultrastructure, in both tissues, consisting of electron-lucent core surrounded by an electron-dense thin rim. The rhodamine B-stained sections also emphasized the identical morphology of the pb in ganglioglioma and LC. Based on the EM comparison, these brightly fluorescing spherical bodies are ideal markers for identifying in LM, the clusters of large neoplastic cells, representing neurons, which are the most important clue to the correct diagnosis of gangliogliomas. 相似文献