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51.
Hakimeh Sadeghian M.D. Farzaneh Ahmadi M.D. Masoumeh Lotfi‐Tokaldany M.D. Rezvanyieh Salehi M.D. Reyhane Zavar M.D. Mahmood Sheikh Fathollahi Seyed Hesameddin Abbasi M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(7):803-808
Background: Longitudinal myocardial tissue velocity imaging (TVI) and strain rate imaging (SRI) quantify regional myocardial function. We aimed to measure TVI and SRI indices for inferobasal aneurysmal segments by echocardiography at rest. Method: Sixteen patients with inferobasal left ventricular (LV) aneurysm, LV ejection fraction (EF) ≤50%, and 14 normal coronaries with normal echocardiography (control group) were studied. In SRI, peak systolic strain (ST), strain rate (SR), and pattern of strain curves and in TVI, peak systolic inward motion (Sm) were evaluated all at rest. Ascending curve means systolic expansion and descending means shortening. Results: LVEF was significantly lower in the patient group. Mean ST, SR, and Sm of inferobasal segment showed significant difference between patient and control groups; for ST: 1.45 ± 7.18% versus ?17.64 ± 7.45%, P < 0.0001; SR: ?0.25 ± 0.26 versus ?1.44 ± 0.64 sec?1, P < 0.0001; and Sm: 3.85 ± 1.26 versus 5.56 ± 1.28 cm/sec, P = 0.006, respectively. All inferobasal aneurysmal segments had ascending curve while normal segments showed a descending curve. In patient group, aneurysmal segments had significantly reduced ST and SR compared to normal segments. Normal functioning segments of patients showed significant reduction of ST and SR compared to normal LV segments in control subjects. The range of SR and ST for inferobasal aneurysmal segments did not overlap with that of the normal segments (?0.60, 0.19 and ?3.00, ?0.80 sec?1 for SR, and ?8.30, 23.30 and ?35.30, ?10.00% for ST, respectively). Conclusion: SRI indices were significantly reduced in inferobasal aneurysmal segment in comparison with either the same segment in normal subjects or normal functioning segments in the same patients. SR and ST may be superior to Sm in the evaluation of inferobasal aneurysmal segments. (Echocardiography 2010;27:803‐808) 相似文献
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Shaghayegh Haghjooy Javanmard Mehdi Nematbakhsh Farzaneh Mahmoodi Mohamad Reza Mohajeri 《Pathophysiology》2009,16(1):9-13
Introduction: Diminished bioavailability of nitric oxide is crucial in endothelial dysfunction and the development of atherosclerosis. Several studies have found that l-arginine as a nitric oxide (NO) donor has beneficial effect in prevention of atherosclerosis, but the mechanism is not completely known. We hypothesized that increased endothelial nitric oxide synthase (eNOS) and/or decreased inducible NOS (iNOS) expressions might be involved in the preventive effects of l-arginine in hypercholesterolemic rabbits. Methods: Seventeen male rabbits were divided randomly in two groups. They received rabbits chow supplemented with 1% cholesterol (group 1, n = 8) and the other group received also l-arginine (3% in drinking water) (group 2, n = 9) for 1 month. Blood samples were obtained before and after the experiment. At the end of experiment, the aortas were harvested. The serum levels of cholesterol and low-density lipoproteins (LDL) were measured. The intima/media thickness (IMT) ratio was measured and the determination of fatty streak formation was done with the aid of light microscopy. eNOS and iNOS expression in aorta were studied with immuohistochemistery. Results: The IMT ratio in first group having fatty streaks was 0.287 ± 0.15. No fatty streak lesion was detected in l-arginine-treated group. The results also indicated that eNOS expression (intensity) in aortas was significantly higher in l-arginine-treated group (group 1: 13.62 ± 2.7 and group 2: 21.77 ± 2.8; p < 0.05), but no significant difference was observed for iNOS expression between the groups. Conclusion: The expression of eNOS plays an important role in the protection of the vessel wall from atherosclerosis. l-Arginine in drinking water has a beneficial effect in the enhancement of eNOS protein expression. 相似文献
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Farker K Merkel U Schweer H Haerting J Madani SF Eggers R Müller UA Seyberth HW Hoffmann A 《European journal of clinical pharmacology》2002,58(2):85-91
OBJECTIVE: To determine the effect of short-term administration of diclofenac-colestyramine on glomerular filtration rate (GFR), renal plasma flow (RPF) and urinary excretion of prostanoids in patients with type-2 diabetes without and with impaired renal function.METHODS: In the randomised, single-blind, placebo-controlled, two-period crossover study, 32 patients with type-2 diabetes (group 1: 16 patients without impaired renal function, creatinine clearance > or =80 ml/min and group 2: 16 patients with impaired renal function, creatinine clearance 30-79 ml/min) received 140 mg diclofenac-colestyramine (corresponding to 75 mg diclofenac sodium) or placebo twice a day on days 1 and 2 and once on day 3 with a wash-out period of 6 days between the two periods. GFR was assessed using both measurement of creatinine clearance and calculation of inulin clearance and RPF was assessed using calculation of para-aminohippurate (PAH) clearance after the short-term administration on day 3. Urinary excretion of prostanoids (PGE(2), PGE-M, 6-keto-PGF(1alpha), 2,3-dinor-6-keto-PGF(1alpha), TxB(2), 2,3-dinor-TxB(2) and 11-dehydro-TxB(2)) were measured before and after drug intake.RESULTS: Comparison with placebo showed no effect of diclofenac-colestyramine on creatinine, inulin or PAH clearance ( P>0.05) in patients with type-2 diabetes either without or with impaired renal function. The differences in creatinine, inulin and PAH clearance between the two groups of patients were not influenced by diclofenac-colestyramine. Urinary excretion of PGE(2), PGE-M, 6-keto-PGF(1alpha), 2,3-dinor-6-keto-PGF(1alpha), TxB(2), 2,3-dinor-TxB(2) ( P=1.89) and 11-dehydro-TxB(2) was significantly reduced by diclofenac-colestyramine.CONCLUSION: These results indicate that proven non-specific cyclooxygenase inhibition by short-term administration of diclofenac-colestyramine did not affect renal haemodynamic function (GFR, RPF) in patients with type-2 diabetes either without or with impaired renal function. 相似文献
57.
Farzaneh P Ebtekar M Hassan ZM Rafati S 《Iranian journal of allergy, asthma, and immunology》2003,2(2):89-93
Although thorough studies on the immune reponse to rubella have been performed, less attention has been given to the cellular mechanism and mediators that shape the process. Specifically, information concerning the nature ofcytokine patterns involved in the immune response to Rubella vaccination is not avaliable. This study deals with cytokine production patterns of spleen cells from Balb/c mice following vaccination with the Takahashi strain of Rubella vaccine. Mice were injected intraperitonealy with Rubella virus and PBS and 7, 10 or 14 days later, spleen cells were separated and cultured with varying doses of virus, con A or only the medium. ELISA assays were performed on supernatants for measurement of IL-4, INF-gamma and IL-5. LTT (Lymphocyte Transformation Test) was also performed. The data indicate variation in cytokine patterns during the time periods after vaccination. On day 7 a type 1 pattern was observed. The LTT response was also indicative of CMI (Cell Mediated Immunity) response on the 7th and 14th days while a transient suppression on day 10 was observed. These results indicate a time dependent cytokine response with variation ultimately leading o a dominant type 1 (Ti) cytokine response. 相似文献
58.
Goichinfar F Madani R Hashemi-Fesharaki R Esmailnya K 《Iranian journal of allergy, asthma, and immunology》2003,2(2):101-105
Bovine tropical Theileriosis caused by Theileria annulata is an economically important disease of cattle. An enzyme linked immunosorbent assay (ELISA) was used to determine antibody levels in vaccinated and unvaccinated cattle, using cellular schizont as antigen and its results were compared with immunofluorescent assay (IFA). For this test 126 sera collected (105 vaccinated, 31 not vaccinated) from cows and assayed with ELISA which among them 104 sera were positive and 32 sera were negative. Same sample assayed with IFA in which 99 were positive sera and 37 were negative sera. Thereby the sensitivity and specificity of this ELISA on comparsion with lEA were 95.5% and 66.6% respectively. This study revealed that ELISA could be successfully used for both differentiating vaccinated and not vaccinated cattle and obtaining the titer of vaccinated cattle. 相似文献
59.
Operative classification of thromboembolic disease determines outcome after pulmonary endarterectomy 总被引:5,自引:0,他引:5
Thistlethwaite PA Mo M Madani MM Deutsch R Blanchard D Kapelanski DP Jamieson SW 《The Journal of thoracic and cardiovascular surgery》2002,124(6):1203-1211
OBJECTIVE: We sought to determine whether type and location of thromboembolic disease in the pulmonary vascular tree predicts the hemodynamic result and clinical outcome in patients undergoing pulmonary endarterectomy. METHODS: From 1998 to 2000, 202 patients with pulmonary hypertension and pulmonary vascular resistance ranging from 194 to 2950 dynes-s-cm(-5) underwent pulmonary endarterectomy. Preoperative and postoperative tricuspid valve function, pulmonary artery pressure, and pulmonary vascular resistance were determined by means of transthoracic echocardiography and measurements with a Swan-Ganz catheter (Edwards Lifesciences, Irvine, Calif), respectively. Patients underwent intraoperative classification of thromboembolism as follows: type 1 (76 patients), fresh thrombus in the main-lobar pulmonary arteries; type 2 (81 patients), intimal thickening and fibrosis proximal to the segmental arteries; type 3 (38 patients), disease within distal segmental arteries only; and type 4 (7 patients), distal arteriolar vasculopathy without visible thromboembolic disease. RESULTS: Overall perioperative mortality was 4.5% (9/202 patients). By means of univariate analysis, patients with type 3 or 4 disease (distal pulmonary vasculopathy) had more residual postoperative tricuspid regurgitation (P <.0001), higher postoperative pulmonary artery systolic pressure (P <.0001), and greater postoperative pulmonary vascular resistance (P <.0001) compared with that seen in patients with type 1 or 2 disease, in whom thromboembolic disease was more surgically accessible. Factors such as severity of preoperative tricuspid regurgitation, patient age, and circulatory arrest time had no correlation with postoperative hemodynamic improvement. Patients with distal thromboembolic disease (type 3-4) had higher perioperative mortality, required longer inotropic support, and had longer hospital stays compared with patients with type 1 or 2 thromboembolic disease. CONCLUSION: The degree of improvement in pulmonary hypertension and tricuspid regurgitation after pulmonary endarterectomy is determined by the type and location of pulmonary thromboembolic disease. Classification of thromboembolism is useful for predicting patient outcome after pulmonary endarterectomy. 相似文献
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