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91.
Overview on the sub-grouping of the crustacean hyperglycemic hormone family   总被引:14,自引:0,他引:14  
The Crustacean hyperglycemic hormones (CHHs) are an ever extending family of crustacean hormones mainly involved in carbohydrate metabolism, molt and reproduction. In this paper, we drew together 32 available CHH sequences, and applied the techniques of multiple sequence alignment, motif searching and amino acid conservation analysis to the characterization of the molecules independently of their biological function. The analysis clearly showed that the proteins clustered into two groups (CHH and VIH). Amino acid conservation analysis also subdivided the VIH group into sequences involved in reproduction (RIH) or in molt (MIH). Motif searching identified five motifs in each group of mature hormones. Motifs A2 and A3 were conserved in all sequences while motifs A1 and A1' were specific of the CHH and VIH groups respectively. This approach demonstrated the S. gregaria ion transport peptides as true members of the CHH group. The two main groups, CHH and VIH, are also discussed in terms of functional homogeneity.  相似文献   
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We report a case of a 71-year-old man with a long coronary artery disease history and two sets of coronary artery bypass grafts. He developed large aortocoronary saphenous vein graft aneurysms in the two grafts from the first set of aortocoronary saphenous venous 20 years later. During the previous 3 years, the aneurysms grew in diameter from 22 to 50 mm. Because of severe renal insufficiency, and in order to avoid jeopardizing the late normal coronary artery bypass grafts by further thoracic surgery, we excluded successfully these altered grafts percutaneously by using 13 coils during the same procedure.  相似文献   
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Motion artifacts of the aorta simulating aortic dissection on spiral CT   总被引:11,自引:0,他引:11  
PURPOSE: Motion artifacts of the ascending aorta may impair image quality and simulate an intimal flap or a false channel. The purpose of this study is to evaluate the prevalence, amplitude, and extent of motion artifacts of the aorta in spiral CT and to specify the effects of acquisition and reconstruction parameters on these artifacts. METHOD: One hundred seventy-one thoracic spiral CT examinations were retrospectively analyzed by two reviewers. The analysis sought to determine the presence, location, amplitude, and extent of artifacts of the ascending aorta. RESULTS: Aortic artifacts were detected on spiral CT in 57% of cases. The mean amplitude and mean extent were 4+/-4 and 6+/-7 mm, respectively. Artifacts in the ascending aorta were significantly higher with the 360 degrees linear interpolation (LI) algorithm than with the 180 degrees LI algorithm. CONCLUSION: The prevalence of motion artifacts on spiral CT is higher in this study than the reported prevalence in incremental CT. However, this higher prevalence is significantly reduced when the 180 degrees LI algorithm is used.  相似文献   
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Germline mutations that activate genes in the canonical RAS/MAPK signaling pathway are responsible for rare human developmental disorders known as RASopathies. Here, we analyzed the molecular determinants of Costello syndrome (CS) using a mouse model expressing HRAS p.G12S, patient skin fibroblasts, hiPSC-derived human cardiomyocytes, a HRAS p.G12V zebrafish model, and human fibroblasts expressing lentiviral constructs carrying HRAS p.G12S or HRAS p.G12A mutations. The findings revealed alteration of mitochondrial proteostasis and defective oxidative phosphorylation in the heart and skeletal muscle of CS mice that were also found in the cell models of the disease. The underpinning mechanisms involved the inhibition of the AMPK signaling pathway by mutant forms of HRAS, leading to alteration of mitochondrial proteostasis and bioenergetics. Pharmacological activation of mitochondrial bioenergetics and quality control restored organelle function in HRAS p.G12A and p.G12S cell models, reduced left ventricle hypertrophy in CS mice, and diminished the occurrence of developmental defects in the CS zebrafish model. Collectively, these findings highlight the importance of mitochondrial proteostasis and bioenergetics in the pathophysiology of RASopathies and suggest that patients with CS may benefit from treatment with mitochondrial modulators.  相似文献   
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(1) Background: The COVID-19 pandemic illuminated vulnerabilities in the Canadian health care system and exposed gaps and challenges across the cancer care continuum. Canada is experiencing significant disruptions to cancer-related services, and the impact these disruptions (delays/deferrals/cancellations) have on the health care system and patients are yet to be determined. Given the potential adverse ramifications, how can Canada’s health care systems build resilience for future threats? (2) Methods: To answer this question, CCC facilitated a series of four thought-leadership roundtables, each representing the views of four different stakeholder groups: patients, physicians, health care system leaders, and researchers. (3) Results: Six themes of strength were identified to serve as a springboard for building resilience including, (1) advancing virtual care and digital health technologies to prevent future interruptions in cancer care delivery. (2) developing real-time data metrics, data sharing, and evidence-based decision-making. (3) enhancing public–private-non-profit partnerships to advance research and strengthen connections across the system. (4) advancing patient-centricity in cancer research to drive and encourage precision medicine approaches to care. (5) investing in training and hiring a robust supply of health care human resources. (6) implementing a national strategy and infrastructure to ensure inter-provincial collaborative data sharing (4). Conclusions: A resilient health care system that can respond to shocks and threats is not an emergency system; it is a robust everyday system that can respond to emergencies.  相似文献   
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