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21.
Ewing’s sarcoma family of tumors (ESFTs) are indicated by malignant, small, round and blue cell tumors of the bone and soft tissue. Gene rearrangements between EWS gene on chromosome 22q12 and members of the ETS gene family are common in and specific to ESFTs. Another defining characteristic of ESFTs is their membranous expression of the CD99. In contrast, such translocations and immunoreactivity are not found in central primitive neuroectodermal tumors (cPNETs). The aim of this study was to investigate the detection of EWS/FLI1 translocations and CD99 immunoreactivity in order to evaluate their clinicopathological features and their roles in the differential diagnosis of these tumors. In this study, we investigated CD99 immunoreactivity using immunohistochemistry and Ewing’s sarcoma / Friend leukaemia virus integration 1 (EWS/FLI1) translocation using the fluorescence in situ hybridization (FISH) method in 23 cases. CD99 expression was detected in 10/11 (90%) ESFT cases and 2/7 cPNET cases. In 18 cases EWS/FLI1 translocation was examined using the FISH method. The EWS/FLI1 translocations were detected in 7/8 (87.5%) ESFTs cases, whereas non of 8 cPNET cases were detected with this translocation. One case could not be classified as either central or peripheral, showed EWS/FLI1 translocation. There was a statistically significant difference in CD99 expression (p = 0.0013) and EWS/FLI1 translocation (p = 0,002) between cPNETs and ESFTs cases. In conclusion, CD99 expression and EWS/FLI1 translocation are specific and sensitive markers in the diagnosis of ESFTs. However, these were often not found in cases of cPNET. Therefore, in the diagnosis of ESFTs, clinical, radiological, histopathological and immunohistochemical parameters should always be evaluated together.  相似文献   
22.
The aim of this study was to examine the intima-media thickness (IMT) of carotid arteries and endothelial function parameters such as plasma asymmetric dimethylarginine (ADMA) and homocysteine levels in hypercholesterolemic children and to investigate the relations of these parameters with hypercholesterolemia. Fifty-seven hypercholesterolemic and 37 healthy children were included in the study. Hypercholesterolemia was defined as 155 mg/dl and above for low-density lipoprotein (LDL)-cholesterol. Plasma concentrations of ADMA and homocysteine were measured and the measurement of carotid IMT was determined. Both carotid IMT and plasma ADMA levels were significantly higher in hypercholesterolemic children than healthy children (p<0.01). No significant difference was determined in homocysteine concentration between hypercholesterolemic children and the control group (p>0.05). No significant correlation was observed between lipid profiles and the levels of ADMA and homocysteine. However, a significant positive correlation was found between carotid IMT and total and LDL-cholesterol levels and between the levels of ADMA and LDL-cholesterol. In conclusion, the progressive increase in ADMA levels and carotid IMT and the positive relationship between carotid IMT and serum cholesterol levels support that plasma ADMA levels and carotid IMT can be indicators of early atherosclerosis in hypercholesterolemic children.  相似文献   
23.
Hepatitis B virus (HBV) continues to be a serious worldwide health problem despite the use of protective HBV vaccines and therapeutic regimens against chronic HBV infection. Chronic HBV patients cannot induce sufficient immune responses against the virus. HBV and its antigens are believed to suppress immune responses during chronic infection. Hence, studying the role of HBV in immune suppression is very important for the development of alternative therapeutic strategies for HBV infections.  相似文献   
24.
Premenstrual syndrome is a term which is used for describing of somatic, cognitive, emotional, and behavioral symptoms that occur during the luteal phase of menstrual cycle in women of reproductive age; symptoms rapidly improve at the onset of menstruation. In this study, we aimed to reveal if cognitive functions are affected or not in PMS and if the subjects are affected, we try to explain this situation by an objective diagnostic test. Ethical committee approval was taken for this project on 09.03.2012 and numbered 050.99-60. In this study, in order to determine premenstrual syndrome, “Premenstrual Syndrome Scale” that is developed by Gençdo?an (2006) with 44 items, Likert type, and 9 subgroups was used. Sample size was calculated using simple random sampling with a confidence level of 95% and confidence interval of 0.05. A total of 60 participants were included in the study (calculated sample size was 30 for each group). Each group was recorded in the ENMG-UP laboratory using the OIP auditory warning and the “oddball two-tone discrimination task” method. Latency measurements were taken from the highest point of the peak, and amplitude measurements were taken from peak to peak with a cursor. Comparisons of P300 wave latencies obtained via sparse auditory stimulus in PMS and non-PMS groups were made and findings were summarized in one of the tables. Recordings are taken from three scalp regions: parietal and central, respectively. PMS women have longer P300 wave latencies in all regions compared to non-PMS group, whereas there is no significant difference between P300 amplitude.  相似文献   
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Retinoblastoma is the primary ocular malignancy affecting children under 6 years of age. The development of second malignant tumors in survivors of hereditary retinoblastoma is a well-known clinical entity and a major cause of morbidity and mortality. Rhabdomyosarcomas as second primary tumors have been only rarely described. The authors report a patient with bilateral retinoblastoma who developed a myogenic sarcoma of the orbit after 5.5 years of diagnosis. The short latency period may be explained by tumor histology with the contribution of radiotherapy and chemotherapy. The prognosis of second tumors is poor despite aggressive treatment.  相似文献   
27.
OBJECTIVES: Neopterin is produced by stimulated macrophages under the influence of gamma interferon of lymphocyte origin. It is regarded as a biochemical marker of cell-mediated immune response. This study was designed to assess the diagnostic value of pleural fluid neopterin levels in tuberculous pleurisy in comparison with adenosine deaminase activity. DESIGN AND METHODS: Pleural fluid adenosine deaminase (ADA) activity and neopterin levels were measured in 16 patients with tuberculous pleurisy (TP) and 19 patients with malignant pleurisy (MP). ADA activity was determined by a colorimetric method, whereas neopterin levels were determined by a reversed-phase liquid chromatography technique. All values were given as median (min-max). RESULTS: The mean age was 45.43+/-20.39 years in the TP group and 60.42+/-11.02 years in the MP group (p=0.026). The median pleural fluid ADA activity was 51.75 U/L (3.50-62.40 U/L) in the TP group and was 2.30 U/L (1-8.20 U/L) in the MP group. The difference was statistically significant (p<0.001). The median pleural fluid neopterin levels were 13.15 nmol/L (1.86-59.50 nmol/L) and 2.44 nmol/L (0.92-27.60 nmol/L) in the TP group and the MP group, respectively (p=0.021). In order to evaluate the diagnostic value of pleural fluid neopterin concentrations, receiver-operating-characteristic curve analysis was performed. CONCLUSION: Pleural fluid neopterin concentration is significantly higher in TP when compared to MP, however when compared, its clinical use as a diagnostic marker is not valuable as ADA.  相似文献   
28.
CONTEXT: Chorioamnionitis (CAM)-elicited preterm delivery (PTD) is associated with elevated amniotic fluid levels of IL-1beta and TNF-alpha. We hypothesized that IL-1beta and TNF-alpha may induce matrix metalloproteinase (MMP)-1 and MMP-3 activity to promote PTD by degrading decidual and fetal membranes and cervical extracellular matrix. OBJECTIVE: Our objective was to evaluate: 1) MMP-1 and MMP-3 expression in decidual sections from uncomplicated term, idiopathic preterm, and CAM-complicated deliveries, and 2) the separate and interactive effects of IL-1beta, TNF-alpha, medroxyprogesterone acetate (MPA), and a p38 MAPK inhibitor (SB203580) on MMP-1 and MMP-3 expression in term decidual cells (DCs). INTERVENTIONS AND MAIN OUTCOME MEASURES: Decidua were immunostained for MMP-1 and MMP-3. Cultured term DCs were incubated with estradiol (E2) or E2 plus MPA with or without IL-1beta or TNF-alpha with or without SB203580. ELISA and Western blotting assessed secreted MMP-1 and MMP-3 levels, quantitative real-time RT-PCR assessed mRNA levels, and substrate gel zymography was used to determined MMP-1 and MMP-3 proteolytic activity. RESULTS: MMP-1 and MMP-3 immunostaining was more prominent in CAM-complicated decidua vs. control preterm and term decidual specimens (P < 0.05). Compared with basal outputs by DCs incubated with E2, TNF-alpha enhanced MMP-1 and MMP-3 secretion by 14 +/- 3- and 9 +/- 2-fold, respectively, and IL-1beta increased MMP-1 and MMP-3 secretion by 13 +/- 3- and 19 +/- 2-fold, respectively (P < 0.05). Addition of MPA lowered basal MMP-1 and MMP-3 outputs by 70%, whereas the TNF-alpha- and IL-1beta-enhanced MMP-1 and MMP-3 levels were blunted by more than 50% (P < 0.05). SB203580 suppressed TNF-alpha- and IL-1beta-induced MMP-1 and MMP-3 secretion by severalfold. Western blotting confirmed the ELISA results, and mRNA levels corresponded with MMP-1 and MMP-3 protein levels. MMP-1 and MMP-3 proteolytic activity was confirmed by substrate gel zymography. CONCLUSION: Augmented DC-expressed MMP-1 and MMP-3 in CAM-complicated pregnancies may promote PTD via decidual, fetal membrane, and cervical extracellular matrix degradation. Effects of progestin-p38 MAPK signaling inhibition on cytokine-enhanced MMP-1 and MMP-3 expression in term DCs suggest alternative mechanisms to prevent CAM-induced PTD.  相似文献   
29.
OBJECTIVE: The purpose of this study was to investigate whether an inguinal hernia would have an impact on the testicular volume and blood flow by scrotal ultrasonography. METHODS: Twenty-six male patients with unilateral inguinal hernias with a mean age of 48.1 years were included in the study. Testicular volumes were calculated, and spectral parameters such as the pulsatility index and resistive index of the testicular artery at supratesticular, subcapsular, and intratesticular levels on both the side with the inguinal hernia and the contralateral side were measured by a preoperative ultrasonographic examination. Comparisons between the dependent groups were performed by a Wilcoxon or paired samples t test where appropriate. RESULTS: The mean +/- SD testicular volume on the side with the inguinal hernia was significantly higher than that on the contralateral testis (15.46+/-4.49 versus 14.54+/-3.65 mL, respectively; P<.05, Student t test). In addition, the mean resistive index of the intratesticular arteries was significantly higher on the side with the hernia compared with the contralateral side (0.66+/-0.06 versus 0.63+/-0.05; P<.05, Student t test). CONCLUSIONS: These data indicate that an inguinal hernia may impair testicular blood flow, which may be attributable to an intermittent mechanical compression effect on the funiculus spermaticus in the inguinal canal.  相似文献   
30.
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