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71.
Type 1 and type 2 cytokine-producing CD4+ and CD8+ T cells in primary antiphospholipid syndrome 总被引:1,自引:0,他引:1
Karakantza M Theodorou GL Meimaris N Mouzaki A John E Andonopoulos AP Maniatis A 《Annals of hematology》2004,83(11):704-711
Antiphospholipid syndrome (APS) is an autoimmune condition characterized by thrombosis and/or recurrent fetal loss as well as the presence of autoantibodies against epitopes present on phospholipid-binding proteins. The role of cellular immunity in the pathogenesis of the syndrome remains unclear. We studied the cellular phenotype and the production of type 1 [interferon (IFN)-, interleukin (IL)-2] and type 2 (IL-4, IL-10) cytokines by CD4+ and CD8+ T-lymphocyte subsets in 13 patients with untreated primary APS (PAPS) and in 32 healthy controls. The production of cytokines was determined in T cells after a 5-h culture with or without mitogenic stimulation using a flow cytometric method of intracellular cytokine staining. In six of the patients these studies were repeated 6 months later. In PAPS patients we found a reduced percentage of circulating CD4+CD45RA+ and an increased percentage and absolute number of CD8+HLA-DR+ cells. A type 1 response was observed in the patients unstimulated cells, indicated by an increase in IFN--producing CD8+, IL-2-producing CD4+ T cells, and a decrease in IL-4-producing CD4+ and CD8+ T cells. Similar results were obtained in the patients at follow-up. Taken together, these results suggest a chronic in vivo stimulation of CD4+ and CD8+ T cells in PAPS patients exhibiting a type 1 polarization. Changes of cellular immunity may contribute to the pathogenesis of the clinical manifestations of the syndrome and might be proven to be useful targets for therapeutic interventions in the future. 相似文献
72.
Endoscopic management and long-term follow-up of Dieulafoy's lesions in the upper GI tract 总被引:15,自引:0,他引:15
Kasapidis P Georgopoulos P Delis V Balatsos V Konstantinidis A Skandalis N 《Gastrointestinal endoscopy》2002,55(4):527-531
BACKGROUND: The aim of this study was to retrospectively evaluate the short-and long-term effectiveness of different methods of endoscopic treatment for bleeding Dieulafoy's lesions. METHODS: Patients were allocated into 2 groups according to the hemostatic method applied: (1) injection group (epinephrine and/or ethanolamine oleate), and (2) thermal coagulation group (heat probe), either alone or combined with epinephrine injection. The combination of epinephrine and ethanolamine oleate was used in 5 patients, epinephrine alone in 3, ethanolamine oleate alone in one, heat probe and epinephrine in 8, and heat probe alone in 1 patient. RESULTS: Dieulafoy's lesions were found in 18 (1%) of 1750 patients with acute nonvariceal upper GI bleeding. Comorbid conditions were present in 5 (28%) patients. Initial hemostasis was achieved endoscopically in 13 patients (72%) and permanent hemostasis in 17 patients (94%). Bleeding recurred in 5 patients (2 with concomitant disease) in the injection group; 3 were successfully retreated by heat probe coagulation and epinephrine injection, 1 with hemoclip application and 1 by surgery. There was no recurrent bleeding in thermal treatment group. Thermal treatment was significantly superior to injection (p = 0.0029). CONCLUSIONS: Endoscopic thermal coagulation with or without epinephrine injection should be the initial treatment of choice for Dieulafoy's lesions. Mortality is lowest in patients with no significant comorbidity and an unremarkable medical history. 相似文献
73.
Effect of octreotide administration on serum interleukin-6 (IL-6) levels of patients with acute edematous pancreatitis 总被引:5,自引:0,他引:5
Nikou GC Giamarellos-Bourboulis EJ Grecka P Toumpanakis Ch Giannikopoulos G Katsilambros N 《Hepato-gastroenterology》2004,51(56):599-602
BACKGROUND/AIMS: Based on former studies in experimental animals on the effect of octreotide on serum and ascitic levels of tumor necrosis factor-alpha and interleukin-6 in the field of necrotizing pancreatitis, the present study was designed to investigate the effect of octreotide on serum interleukin-6 of patients with acute edematous pancreatitis. METHODOLOGY: A total of 36 patients with acute edematous pancreatitis and initiation of symptoms 12 hours before their admission were enrolled in the study; 20 were treated with octreotide 200 microg tid and 16 with octreotide 500 microg tid for five days. Blood was sampled at regular time intervals. Interleukin-6 was determined by an enzyme-immunoassay and C-reactive protein by nephelometry. RESULTS: Mean concentrations of interleukin-6 of patients treated with octreotide 200 microg tid were 59.52 pg/mL before and 94.08, 46.25, 49.94, 58.16 and 26.08 pg/mL at 3, 6, 24, 48 and 72 hours after the start of therapy respectively. Respective values of patients treated with octreotide 500 microg tid were 57.19, 53.07, 57.83, 36.06, 54.29 and 65.49 pg/mL. Mean C-reactive protein of patients treated with octreotide 200 microg tid were 67.37 mg/L before and 48.51, 106.08 and 95.58 mg/L at 24, 48 and 72 hours after the start of therapy respectively. Respective values of patients treated with octreotide 500 microg tid were 65.51, 60.56, 90.68 and 64.22 mg/L. CONCLUSIONS: A transient, but not statistically significant, decrease of serum interleukin-6 levels was documented after administration of octreotide in the field of acute edematous pancreatitis. That decrease was earlier after the application of the 500 microg tid dose than the 200 microg tid dose. Studies with a greater number of patients are mandatory to fully clarify the effect of octreotide, if any, on acute pancreatitis. 相似文献
74.
Nikolaos A Koutlianos Evangelia J Kouidi Thomas I Metaxas Asterios P Deligiannis 《European journal of cardiovascular prevention and rehabilitation》2004,11(5):435-441
BACKGROUND: Cardiac disorders constitute the most common causes of sudden cardiac death (SCD) and mitral valve prolapse (MVP) is one of the cardiac structural causes in young populations. The aim of this study was to evaluate some reliable non-invasive electrophysiological variables of SCD in young athletes with mild or moderate MVP and to compare them with their cardiorespiratory adaptations. DESIGN: The study population comprised of 40 amateur male soccer players, who were equally subdivided into those with (group A, aged 20.4+/-4.5 years) and without (group B, 18.4+/-2.4 years) MVP and 20 healthy age-matched sedentary individuals (group C). METHODS: All subjects underwent echo study for left ventricular mass index (LVMI) estimation, treadmill spiro-ergometric test for maximal oxygen uptake (VO2max) measurement and continuous ambulatory 24-h ECG recordings for arrhythmias detection and heart rate variability (HRV) analysis. Furthermore, groups A and B were also submitted to signal-averaged electrocardiogram for late potentials (LP) assessment and to submaximal exercise test for T-wave alternans (TWA) detection. RESULTS: Maximal oxygen uptake, LVMI and HRV index were enhanced in all athletes compared to group C (P<0.05). Resting QTc interval was significantly prolonged only in group B (by 3.7%) compared to C (P<0.05), whereas no significant difference was found between A and B. No positive LP or TWA were observed in all subjects. Significant correlation was found only between HRV index and VO2max in all groups. CONCLUSIONS: Athletes with mild or moderate MVP do not present any significant difference in non-invasive cardiac electrophysiological indices as well as in cardiorespiratory performance, compared to healthy ones. It seems that long-term exercise induced adaptations overlap any cardiac autonomic disorders in cases of mild-to-moderate MVP severity. 相似文献
75.
Vasileios Peppes George Rammos Efstathios Manios Eleni Koroboki Stylianos Rokas Nikolaos Zakopoulos 《Clinical Interventions in Aging》2008,3(4):699-710
Background
Our objective was to associate serum levels of myocardial enzymes and inflammatory biomarkers with severity of coronary artery disease (CAD).Patients and methods
123 patients participated in our study, including 65 cases of acute myocardial infarction (MI), 27 cases of newly diagnosed CAD – without MI – and 31 controls. In all subjects, myocardial serum enzyme levels (creatine phosphokinase, aspartate aminotransferase, lactate dehydrogenase) and inflammatory indices (C-reactive protein, fibrinogen, white blood cells, and erythrocyte sedimentation rate) were measured. Patients were all submitted to coronary angiography and CAD severity was evaluated by Gensini score.Results
Significant differences concerning enzyme serum levels and inflammatory indices were found to exist between the three study groups, being highest among patients with acute MI (p < 0.001). A significant association was demonstrated between Gensini score and serum enzyme levels as well as inflammatory biomarkers.Conclusions
Our findings suggest that serum levels of myocardial enzymes and inflammatory indices correlate with CAD severity in Greek patients. 相似文献76.
77.
Dimitrios-Efthymios G. Vlachos Vasilios Pergialiotis Nikolaos Papantoniou Stamoulis Trompoukis Georgios D. Vlachos 《The journal of maternal-fetal & neonatal medicine》2015,28(12):1421-1427
Despite the widespread usage of oxytocin, there is still no consensus on its mode of administration. The scope of the present meta-analysis was to assess the effect of oxytocin discontinuation after the active phase of labor is established on maternal fetal and neonatal outcomes. We searched Medline, Scopus, Popline, ClinicalTrials.gov and Google Scholar databases. Eight studies were finally retrieved, which involved 1232 parturient. We observed significantly decreased rates of cesarean sections among parturient that discontinued oxytocin (OR 0.51, 95% CI 0.35, 0.74) as well as decreased rates of uterine hyperstimulation (OR 0.33, 95% CI 0.19, 0.58). Similarly, cases of non-reassuring fetal heart rates were fewer among women that did not receive oxytocin after the establishment of the active phase of labor (OR 0.63, 95% CI 0.41, 0.97). Keeping in mind the aforementioned maternal and neonatal adverse effects that seem to result from infusion of oxytocin until delivery, future practice should aim towards its discontinuation after the establishment of the active phase of labor, as it does not seem to influence the total duration of labor. Future studies should aim towards specific populations of parturient in order to clarify whether different approaches are needed. 相似文献
78.
Electrophysiological markers predicting impeding AV‐block during ablation of atrioventricular nodal reentry tachycardia 下载免费PDF全文
Nikolaos Fragakis MD PhD Lydia Krexi MD Panagiota Kyriakou MD PhD Melani Sotiriadou MD Charalambos Lazaridis MD Athanasios Karamanolis MD Panagiotis Dalampyras MD Stelios Tsakiroglou Vassilios Skeberis MD PhD Dimitrios Tsalikakis PhD Vassilios Vassilikos MD PhD 《Pacing and clinical electrophysiology : PACE》2018,41(1):7-13
1 Background
Radiofrequency (RF) ablation of the slow pathway (SP) in atrioventricular nodal reentry tachycardia (AVNRT) is occasionally complicated with atrioventricular block (AVB) often predicted by junctional beats (JB) with loss of ventriculo‐atrial (VA) conduction.2 Methods
We analyzed retrospectively 153 patients undergoing ablation of SP for typical AVNRT. Patients were divided into two age groups: 127 ≤ 70 years and 26 > 70 years. We analyzed the interval between the atrial electrogram in the His‐bundle position and the distal ablation catheter [A(H)‐A(RFd)] and between the distal ablation catheter and the proximal coronary sinus catheter [A(RFd)‐A(CS)] before RF applications with and without JB. We evaluated if these intervals can be used as predictors of JB incidence and also of JB with loss of VA conduction. We also assessed if age influences the risk of loss of VA conduction.3 Results
The A(H)‐A(RFd) and A(RFd)‐A(CS) intervals were significantly shorter in RF applications causing JB than those without JB (33 ± 11 ms vs 39 ± 9 ms, P < 0.001, 14 ± 9 ms vs 20 ± 7 ms, P < 0.001, respectively). The A(H)‐A(RFd) and A(RFd)‐A(CS) intervals were also significantly shorter in RFs causing JB with VA block than those with VA conduction (29 ± 11 ms vs 35 ± 11 ms, P < 0.001, 8 ± 8 ms vs 17 ± 8 ms, P < 0.001, respectively). Patients > 70 years had shorter intervals (36 ± 11 ms vs 29 ± 8 ms, P = 0.012, 17 ± 8 ms vs 13 ± 7 ms, P = 0.027, respectively), while VA block was more common in this age group.4 Conclusions
The A(H)‐A(RFd) and A(RFd)‐A(CS) intervals can be used as markers for predicting JB occurrence as well as impending AVB. JB with loss of VA conduction occur more often in older patients possibly due to a higher position of SP. 相似文献79.
80.
Marilita M. Moschos Nikolaos Kokolakis Maria Gazouli Irini P. Chatziralli Dimitrios Droutsas Nicholas P. Anagnou 《Ophthalmic genetics》2015,36(3):213-217
Background: A number of mutations in the VSX1 and SOD1 genes have been reported to be associated with keratoconus (KC), however the results from different studies are controversial. In this study, we conducted the genotyping of common polymorphisms [VSX1: D144E, H244R, R166W, G160D; SOD1: intronic 7-base deletion (c.169?+?50delTAAACAG)], in a case–control sample panel of the Greek population.Materials and methods: A case–control panel, with 33 KC patients and 78 healthy controls, were surveyed. DNA from each individual was tested for the VSX1: D144E, H244R, R166W, G160D and SOD1: intronic 7-base deletion (c.169?+?50delTAAACAG) polymorphisms by direct sequencing.Results: We observed no polymorphisms of the VSX1 gene in the case–control panel. Concerning the SOD1 intronic 7-base deletion (c.169?+?50delTAAACAG), our findings suggest that heterozygous carriers are over-represented among KC cases compared to healthy controls (p?=?0.002).Conclusions: We cannot confirm the previously reported association of the polymorphism in the VSX1 gene with KC. Our results suggest a possible causative role of SOD1 in the pathogenesis of KC. Further studies are required to identify other important genetic factors involved in the pathogenesis and progression of KC. 相似文献