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Background: Predictors of aortic dilatation are not well‐described in patients with bicuspid aortic valve (BAV). Changes in extracellular matrix composition in the aortic wall may play an important role. Our study aimed to examine the relationship between ascending aortic dilatation and biochemical markers for collagen metabolism, such as matrix metalloproteinase‐2 (MMP‐2) and matrix metalloproteinase‐9 (MMP‐9) levels in patients with BAV. Methods: All patients underwent cardiac echocardiography using a standard protocol, and aortic measurements were made in end‐diastole. One hundred twelve BAV patients with no or mild valvular impairment were recruited and grouped according to the aortic dimensions corrected for body surface area (BSA) and age. There were 54 patients with dilated ascending aorta (Group 1) and 58 patients with nondilated ascending aorta (group 2). The plasma levels of MMP‐2 and MMP‐9 were determined by ELISA. Results: The mean ascending aorta diameter was 4.49 ± 0.49 mm in group 1 and 3.51 ± 0.46 mm in group 2 (P < 0.001). There were no significant difference in gender, BSA, presence of hypertension, diabetes mellitus, hyperlipidemia, and smoking between the 2 groups. Nevertheless, no significant difference was observed in the levels of MMP‐2 and MMP‐9 between the 2 groups. The ascending aorta diameter correlated significantly with age (r = 0.438 P < 0.001). No significant correlation was observed between plasma MMP‐2 and MMP‐9 concentration and ascending aorta diameter, respectively (r = ?0.005 P = 0.58, r = ?0.106 P = 0.07). Multivariate analysis showed that age was independent predictor of aortic dilatation (P ≤ 0.001). Conclusion: Age was an independent predictor of aortic dilatation in patients with BAV, whereas MMP‐2 and 9 levels were not relevant by aortic dilatation.  相似文献   
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OBJECTIVES: The vena contracta is the narrowest region of the regurgitant or stenotic jet just downstream the orifice and reflects the size of that orifice. This study was performed to assess the accuracy of the vena contracta width (VCW) in evaluating the severity of mitral stenosis (MS) and to compare the mitral valve area (MVA) determined by VCW with MVAs obtained by other more traditional echocardiographic methods. METHODS: We studied 59 patients (43 females, 42 +/- 14 years) with MS. VCW was measured in the apical four chamber view by Doppler color flow mapping. The largest diameter of the VCW during diastole was measured for at least three cardiac cycles and averaged. MVA was calculated from the following equation: pir(2), where r = VCW/2. MVA was also determined by planimetry, the pressure half-time method, and by the Gorlin formula. RESULTS: In this study, the width of the vena contracta ranged from 0.89 to 1.73 cm (mean 1.30 +/- 0.21). MVA, calculated based on the VCW, ranged from 0.63 to 2.35 cm(2) (mean 1.36 +/- 0.41). MVA by VCW (1.36 +/- 0.41 cm(2)) showed good correlations with three comparative techniques: (1) the cross-sectional area by planimetry (1.35 +/- 0.36 cm(2), mean difference = 0.21 +/- 0.16 cm(2), y = 0.91x + 0.14, r = 0.79, SEE = 0.26 cm(2), p < 0.001); (2) the area derived from the Doppler pressure half-time (1.27 +/- 0.32 cm(2), mean difference = 0.22 +/- 0.19 cm(2), y = 0.97x + 0.13, r = 0.76, SEE = 0.27 cm(2), p < 0.001), and (3) the area derived from the Gorlin equation in the 18 patients who underwent catheterization (1.27 +/- 0.35 cm(2), mean difference = 0.19 +/- 0.16, y = 0.98x + 0.05, r = 0.81, SEE = 0.26 cm(2), p < 0.001). CONCLUSIONS: These findings suggest that Doppler color flow imaging of the MS jet in the vena contracta can provide an accurate estimation of MVA and appears to be potentially applicable in the assessment of the severity of MS.  相似文献   
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Background: The ventricular late potential (VLP) detected using the technique of signal average electrocardiography (SAECG) interacts with several factors, primarily time. Method: In this study, we examined the interaction, over time, of VLP with the initial ischemic burden and enzyme levels in acute myocardial infarction. Patients diagnosed as having acute myocardial infarction were included in the study. On the first day, the patients underwent enzyme analysis and electrocardiography (ECG) follow‐up every 6 hours. A 24‐hour ambulatory ECG was performed on the seventh day in order to determine the ischemic burden. SAECG findings (TQRS, RMS, LAS were obtained on the seventh day, in the first and third months. The study was continued with the patients who did not require angioplasty as decided with angiographic evaluation in the first month. Results: The study included 30 patients with acute myocardial infarction (mean age 51 ± 12, 28 males and 2 females). The initial mean CK‐MB levels and the mean ischemic burden were 98 ± 31 U/L and 44 ± 96 minutes. The TQRS (ms), LAS (ms), and RMS (μV) values (mean ± SD) obtained at day 7, month 1, and month 3 are 97 ± 12, 96 ± 9, 103 ± 11, P = 0.01; 31 ± 10, 31 ± 11, 32 ± 10, P = 0.46; 43 ± 28, 41 ± 26, 33 ± 25, P = 0.01, respectively. We observed that the TQRS and RMS values changed significantly with time, but these levels of significance disappeared when adjusted for the initial ischemic burden and CK‐MB levels (P = 0.06; P = 0.53). The VLP frequency was 33% at day 7 and 23% at month 3. Unlike the CK‐MB level, the initial ischemic burden was significantly different between the patients with and without VLP at month 3 (150.85 ± 149.28, 12.34 ± 26.48, P = 0.001). When tested together with age and gender, it was found that the high initial ischemic burden increased the possibility of VLP (OR: 24, Cl: 2.09–279.52, P = 0.01) at month 3. Conclusion: SAECG findings in patients with myocardial infarction changed with time; however, this change occurred depending on the initial ischemic burden and CK‐MB levels. Of these, only the initial ischemic burden, especially in high levels, was a determinant for the presence of VLP in the late period of myocardial infarction. A.N.E. 2002;7(3):242–246  相似文献   
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The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies. The FNFs synthesized by an encouraging and novel approach not only showed high stabilities but also much enhanced catalytic activities as compared to free and conventionally immobilized enzymes. A recent development demonstrated that FNF formation has moved beyond the initial discovery in which enzymes and Cu2+ ions used as the organic and inorganic parts, respectively, are replaced with new organic (chitosan, amino acid and plant extracts) and inorganic (Cu2+ and Fe2+) materials. The new organic materials incorporated into FNFs act as Fenton-like agents and then show peroxidase-like activity owing to the metal ions and the porous structure of FNFs in the presence of hydrogen peroxide (H2O2). All FNFs have been widely utilized in many different scientific and industrial fields due to their greatly enhanced activities and stabilities. This review focuses primarily on the preparation, characterization, and bioanalytical applications of FNFs and explains the mechanisms of their formation and enhanced activities and stabilities.

The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies.  相似文献   
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OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies.  相似文献   
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The number of adolescent refugees around the world has been continuously increasing over the past few years trying to escape war and terror, among other things. Such experience not only increases the risk for mental health problems including anxiety, depression, and post-traumatic stress disorder (PTSD), but also may have implications for socio-cognitive development. This study tested cognitive-affective processing in refugee adolescents who had escaped armed conflict in Syria and now resided in Istanbul, Turkey. Adolescents were split into a high trauma (n = 31, 12 girls, mean age = 11.70 years, SD = 1.15 years) and low trauma (n = 27, 14 girls, mean age = 11.07 years, SD = 1.39 years) symptom group using median split, and performed a working memory task with emotional distraction to assess cognitive control and a surprise faces task to assess emotional interpretation bias. The results indicated that high (vs. low) trauma symptom youth were ~ 20% worse correctly remembering the spatial location of a cue, although both groups performed at very low levels. However, this finding was not modulated by emotion. In addition, although all youths also had a ~ 20% bias toward interpreting ambiguous (surprise) faces as more negative, the high (vs. low) symptom youth were faster when allocating such a face to the positive (vs. negative) emotion category. The findings suggest the impact of war-related trauma on cognitive-affective processes essential to healthy development.

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