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The Effects of Successful Percutaneous Mitral Balloon Valvuloplasty on Acute and Intermediate Term Aortic Stiffness 下载免费PDF全文
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Selami Gurkan Ozcan Gur Demet Ozkaramanli Gur Semil Selcen Gocmez Turan Ege 《Annals of thoracic and cardiovascular surgery》2015,21(2):146-150
Background: Adrenergic tonus is increased in atherosclerotic coronary arteries. In this study, we aimed to demonstrate in vitro effects of phentolamine, a reversible nonselective alpha (α) adrenergic blocker, on coronary artery bypass grafts (CABG) and compare its effects in diabetic and nondiabetic patients.Methods: A total number of 30 patients (15 diabetic and 15 nondiabetic) who were assigned to elective CABG surgery were enrolled into the study. For both groups of patients, 16 internal mammarian artery (IMA) samples, 16 saphenous vein (SV) samples and 16 radial artery (RA) samples were collected and studied in the tissue bath system. The vasodilatation responses to increasing doses of phentolamine were recorded.Results: When grafts were compared in terms of amount of vasodilatation to phentolamine, IMA had the most prominent vasodilatation followed by RA and SV respectively. Although the vasodilatation responses in nondiabetic patients were numerically higher than diabetic patients, there was no statistically difference between the groups.Conclusion: Phentolamine, a nonselective α adrenergic blocker, is proven to have equal vasodilatory effects in diabetic and nondiabetic CABG grafts and can safely be used both intravenously and topically in the perioperative period. 相似文献
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Axial pattern flaps are characterized by a single vascular pedicle that supplies the whole flap and carry the danger of flap loss. For this reason, monitoring and early identification of vascular perfusion is important for flap prognosis. The most commonly used method for flap monitoring is clinical assessment, but it has certain limitations. The bioelectrical properties of tissues can be affected by ischemic conditions, and a preliminary study showed that the bioelectrical resistance of blood was decreased under thrombotic conditions. In this controlled study, the resistance values of the axial flaps were calculated during thrombosis. A total of 28 rats were randomly divided into a control group (n = 14) and an experimental group (n = 14). Axial flaps were elevated based on the inferior epigastric pedicle. For the ischemic group, microvascular clamps were placed in the ischemic group to produce artificial thrombosis from day 1 of the experiment. Bioelectrical resistance was measured every 30 minutes for the first 6 hours and then daily after that. The resistance values from the ischemic group decreased progressively, and 150 minutes after the clamping, the difference became statistically significant (P < 0.05). The results showed that the assessment of flap resistance is a valuable tool and may allow early recognition of a compromise in the vascular system before clinical signs become obvious. 相似文献
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Background: Although recent studies focused on the role of human herpesviruses in various types of periodontal disease, there was a lack of information in these reports regarding the role of pregnancy gingivitis. The aim of this study is to determine the correlation between pregnancy and the subgingival virus presence and their relationship with clinical parameters. Methods: Seventy pregnant and 40 non‐pregnant women were examined for gingival and plaque indices, bleeding on probing (BOP), and clinical probing depths (PDs) from the whole dentition. Subgingival plaque samples were obtained from sites showing signs of gingivitis and healthy sites. The polymerase chain reaction methodology was used to detect cytomegalovirus (CMV) and Epstein‐Barr virus (EBV) from plaque samples. Results: Our results show that gingivitis lesions in 27 (38.6%) and 10 (14.3%) pregnant patients were positive for EBV and CMV, respectively. In the non‐pregnant group, EBV and CMV were detected in six (15%) and eight (20%) lesions, respectively. A statistically significant difference (P <0.01) was found between the subgingival occurrence of EBV in the two groups. In gingivitis sites, clinical PDs were affected by gestation (P <0.001) and the occurrence of EBV (P <0.001). In healthy sites, clinical PDs were affected by gestation (P <0.05), and BOP was affected by the occurrence of CMV and EBV (P <0.001). Conclusion: Our data indicate that pregnancy increased the risk of the presence of subgingival EBV in pregnant women by 3.647 times more than in non‐pregnant women. 相似文献
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Effects of combined systemic administration of low-dose doxycycline and alendronate on endotoxin-induced periodontitis in rats 总被引:3,自引:0,他引:3
Buduneli E Vardar S Buduneli N Berdeli AH Türkoğlu O Başkesen A Atilla G 《Journal of periodontology》2004,75(11):1516-1523
BACKGROUND: Doxycycline has been widely used in periodontal treatment for its antimicrobial and anti-enzymatic effects. Recently, bisphosphonates have been shown to inhibit alveolar bone resorption. The aim of the present study was to evaluate the effects of doxycycline and the bisphosphonate alendronate on the gingival tissue levels of prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha), leukotriene B4 (LTB4), and platelet-activating factor (PAF) in endotoxin-induced periodontal breakdown in rats. METHODS: Experimental periodontitis was induced by repeated injection of Escherichia coli endotoxin (LPS) and 44 adult male Sprague-Dawley rats were divided into five study groups as follows: LPS, doxycycline + LPS, alendronate + LPS, doxycycline + alendronate + LPS, and saline control. Doxycycline and alendronate were given either as a single agent or as a combination therapy during the 7-day study period. At the end of the 1-week protocol, the rats were sacrificed, the gingival tissues were dissected and extracted, and the extracts were analyzed for PGE2, PGF2alpha, LTB4, and PAF levels. The defleshed jaws were analyzed morphometrically for alveolar bone loss. Data were evaluated statistically by using parametric tests. RESULTS: Alveolar bone loss measurements revealed significantly higher values in LPS, doxycycline + LPS, alendronate + LPS, and doxycycline + alendronate + LPS groups in comparison to the saline control group (P <0.05). Combined administration of doxycycline and alendronate exhibited the most prominent inhibition on gingival tissue levels of PGE2 and PGF2alpha (P<0.05). Doxycycline + alendronate + LPS group also significantly reduced LTB4 and PAF levels, although doxycycline provided the most reduction in the levels of these mediators (P <0.05). CONCLUSIONS: Alendronate and/or doxycycline may provide significant inhibition of the major inflammatory mediators of periodontal tissue destruction, and combined administration of these agents may provide beneficial effects in periodontal treatment. However, this hypothesis must be further verified by clinical human trials before introducing its use in dental practice. 相似文献
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Therapeutic versus prophylactic plus therapeutic administration of omega-3 fatty acid on endotoxin-induced periodontitis in rats 总被引:2,自引:0,他引:2
Vardar S Buduneli E Türkoğlu O Berdeli AH Baylas H Başkesen A Atilla G 《Journal of periodontology》2004,75(12):1640-1646
BACKGROUND: The aim of the present study was 1) to evaluate the possible effects of therapeutic usage of omega-3 fatty acid on the gingival tissue levels of prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha), platelet activating factor (PAF), and leukotriene B4 (LTB4) in endotoxin-induced periodontitis in rats and 2) to investigate whether prophylactic usage provides any additional benefits to therapeutic doses of omega-3 fatty acid. METHODS: Experimental periodontitis was induced by repeated injection of Escherichia coli lipopolysaccharide (LPS). Thirty-six adult male Sprague-Dawley rats were divided into four study groups: 1) saline controls; 2) LPS; 3) therapeutic omega-3 fatty acid (TO3); and 4) prophylactic plus therapeutic omega-3 fatty acid (P + TO3) groups. In TO3 group, omega-3 fatty acid was given for 15 days following induction of experimental periodontitis. In P + TO3 group, omega-3 fatty acid was started 15 days before baseline, and then periodontitis was induced at baseline and omega-3 fatty acid was continued for 15 days after baseline. On day 15 after baseline, all rats were anesthetized and sacrificed. PGE2, PGF2alpha, and LTB4 levels in gingival tissue samples were analyzed by enzyme immunoassay and PAF levels were analyzed by radioimmonoassay. Data were evaluated statistically by using parametric tests. RESULTS: LPS injection resulted in significant amount of bone loss (P<0.05). Neither therapeutic nor prophylactic plus therapeutic administration of omega-3 fatty acid with the doses and duration of therapy used in the present study was effective in preventing endotoxin-induced alveolar bone loss. TO3 group exhibited significant decreases in the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF compared to the LPS group (P<0.05). PGE2 and PGF2alpha levels in TO3 group were similar to those of the saline group (P>0.05), while LTB4 and PAF levels were statistically higher than the saline group (P<0.05). Prophylactic plus therapeutic usage of omega-3 fatty acid provided similar levels of all these mediators to those of the saline controls (P>0.05). CONCLUSIONS: Therapeutic omega-3 fatty acid significantly reduced the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF in experimental periodontitis. Furthermore, prophylactic usage of omega-3 fatty acid provided additional beneficial effects to the therapeutic administration by decreasing the gingival tissue levels of these mediators to levels of healthy tissue. These findings should be verified by longitudinal clinical trials investigating clinical and biochemical periodontal parameters to better define the possible role of omega-3 fatty acids in periodontal treatment. 相似文献
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Ayşegül Doğan Selami Demirci Dilek Telci Serli Canikyan Merve Kongur Bülent Dede Fikrettin Şahin 《International urology and nephrology》2018,50(2):247-255
Purpose
Renal cell carcinoma (RCC) accounts for approximately 80% of the primary renal cancers, and current treatment strategies are not sufficient to provide a certain solution. Since there are not many treatment options, interest in discovery of alternative drugs has increased.Methods
In the current study, anticancer activity of a novel heterodinuclear Cu(II)–Mn(II) complex (Schiff base—SB) in combination with poly(ethylene oxide) and poly(propylene oxide) block copolymer (pluronic) P85 was tested against RCC. Cell viability, apoptosis and gene expression analysis were conducted in vitro by using Renca cells.Results
The results revealed that the SB–P85 combination decreased cell proliferation by increasing the apoptotic gene expressions and apoptosis. Renca-injected BALB/c mice were used to mimic early stage of RCC model. Treatment with SB–P85 combination suppressed tumor formation and growth compared to baseline.Conclusion
Overall, SB–P85 showed promising anticancer activity against RCC in vitro and in vivo.10.