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A series of novel phloroglucinol derivatives were designed, synthesized, characterized spectroscopically and tested for their inhibitory activity against selected metabolic enzymes, including α‐glycosidase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase I and II (hCA I and II). These compounds displayed nanomolar inhibition levels and showed Ki values of 1.14–3.92 nM against AChE, 0.24–1.64 nM against BChE, 6.73–51.10 nM against α‐glycosidase, 1.80–5.10 nM against hCA I, and 1.14–5.45 nM against hCA II.
  相似文献   
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Aim: To evaluate the effects of sunitinib (0.5?mg/ml) and bevacizumab (5?mg/ml) on VEGF-A, VEGFR-2 and microRNA (miRNA) levels on corneal neovascularization (CNV).

Methods: In this study, CNV was induced by silver nitrate application to the cornea, and 40 Albino male rats were equally divided into four subgroups:

Group 1 (sunitinib): After silver nitrate application to the cornea, 0.5?mg/ml sunitinib eyedrop was administered twice daily for two weeks (n?=?10).

Group 2 (bevacizumab): After silver nitrate application to the cornea, 5?mg/ml bevacizumab eyedrop was administered twice daily for two weeks (n?=?10).

Group 3 (control): After silver nitrate application to the cornea, normal saline eyedrop was administered twice daily for two weeks (n?=?10).

Group 4 (vehicle): After silver nitrate application to the cornea, 1% DMSO eyedrop was administered twice daily for two weeks (n?=?10).

After two weeks from the silver nitrate application, corneas were evaluated by hand-held biomicroscope for their vascularization status. Then, corneas were excised and the expression levels of VEGFR-2, VEGF-A and the common miRNA markers for neovascularization (miR-15?b, miR-16, miR-23a, miR-126, miR-188, miR-210, miR-221, miR-222, miR-410 and miR-423) were evaluated by real-time PCR.

Results: It was seen that the CNV was decreased in sunitinib- and bevacizumab-administered groups compared to the control and DMSO groups. Also, in comparison with the control group; VEGF-A expression was downregulated by nearly 0.75 times in sunitinib group and nearly 0.52 times in bevacizumab group. VEGFR-2 expression was downregulated by 0.89 times in sunitinib group and 0.68 times in bevacizumab group, compared to the control group. miR-15?b, miR-16 and miR-126 levels were statistically lower in sunitinib and bevacizumab groups, but miR-188 and miR-410 levels were two-fold higher compared to the control group. The miR-210 level was found higher only in sunitinib group compared to the control group. There were no statistically significant changes in miR-23a, miR-221, miR-222 and miR-423 levels among the groups.

Conclusion: Topical application of bevacizumab (5?mg/ml) and sunitinib (0.5?mg/ml) decreases the levels of VEGFR-2 and VEGF-A in CNV. Further studies are needed for detailed analysis of genes which are targeted by up- or downregulated miRNAs in this study.  相似文献   
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Within the spectrum of acute aortic syndromes, intramural hematoma (IMH) is a distinct lesion that is characterized by crescentic or circumferential thickening of the aortic wall in the absence of an intimal defect. The reported incidence of IMH among all type A acute aortic syndromes ranges from 3.5% to 28.3%. As compared with acute aortic dissection, IMH is a disease of the elderly, and it tends to have reduced rates of malperfusion syndromes, aortic insufficiency, and root dilation, yet also tends to have increased rates of pericardial effusion, cardiac tamponade, and periaortic hematoma. With respect to natural history, IMH may progress to classic dissection, frank rupture, or aneurysmal dilation; yet, IMH may also regress and be completely resorbed. However, studies disagree over the rates of progression or regression; as such, few studies agree on the short-term and long-term prognosis associated with IMH. American and European guidelines advocate emergent surgery for all acutely presenting type A IMH. At a minimum, supracoronary replacement of the aorta with hemiarch reconstruction is the preferred extent of operative repair to reduce rates of long-term reintervention for disease progression. However, valve and/or root procedures may be necessary proximally, while total arch reconstruction or hybrid procedures for the descending aorta may be necessary distally. Much remains unknown for IMH, including the ideal extent of aortic repair, risk-stratification for elderly patients, and the optimal treatment paradigm for stable, uncomplicated IMH. As such, IMH remains a diagnostic and therapeutic challenge for the cardiovascular surgeon.  相似文献   
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