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Tom De Beule T Boulanger S Heye WJ van Rooij WH van Zwam L Stockx 《Interventional neuroradiology》2021,27(1):51
Background and purposeFlow diverters are increasingly used to treat intracranial aneurysms. We report the safety and efficacy of the p64 flow diverter, a resheathable and detachable device for intracranial aneurysms.Materials and methodsWe retrospectively reviewed 108 patients with 109 aneurysms treated with the p64 between March 2014 and July 2019. There were 87 women and 21 men, mean age 57 years. Of 109 aneurysms, 74 were discovered incidentally, 12 were symptomatic, 18 were previously treated, and five were ruptured dissection aneurysms. A total of 10 aneurysms were located in the posterior circulation. The mean aneurysm or remnant size was 8.1 mm.ResultsHemorrhage by perforation with the distal guidewire occurred in two patients with permanent neurological deficits in one. In one patient, acute in-stent occlusion caused infarction with a permanent deficit. Permanent morbidity was 1.9% (2 of 108, 95%CI 0.1–6.9%); there was no mortality. During follow-up, three in-stent occlusions occurred, all asymptomatic. There were no delayed hemorrhagic complications. At six months, 77 of 96 aneurysms (80.2%) were completely occluded, and at last follow-up, this increased to 93 of 96 aneurysms (96.9%). In-stent stenosis at any degree occurred in 11 patients, progressing to asymptomatic complete occlusion in one. In the other patients, stenosis resolved or improved at further follow-up.ConclusionThe p64 offers an effective and safe treatment option. Aneurysm occlusion rate was 97% at last follow-up, mostly achieved with a single device. There were no delayed hemorrhagic complications. Delayed in-stent stenosis infrequently progresses to occlusion but remains a matter of concern. 相似文献
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Zhao Li Chao‐Hsiung Hsu Nikolay Dimitrov Dennis W. Hwang Hsin‐Wei Chang Lian‐Pin Hwang Yung‐Ya Lin 《Magnetic resonance in medicine》2015,73(1):spcone-spcone
This review provides a summary statement of recommended implementations of arterial spin labeling (ASL) for clinical applications. It is a consensus of the ISMRM Perfusion Study Group and the European ASL in Dementia consortium, both of whom met to reach this consensus in October 2012 in Amsterdam. Although ASL continues to undergo rapid technical development, we believe that current ASL methods are robust and ready to provide useful clinical information, and that a consensus statement on recommended implementations will help the clinical community to adopt a standardized approach. In this review, we describe the major considerations and trade‐offs in implementing an ASL protocol and provide specific recommendations for a standard approach. Our conclusion is that as an optimal default implementation, we recommend pseudo‐continuous labeling, background suppression, a segmented three‐dimensional readout without vascular crushing gradients, and calculation and presentation of both label/control difference images and cerebral blood flow in absolute units using a simplified model. Magn Reson Med 73:102–116, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
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Dysregulated TGF‐β signaling alters bone microstructure in a mouse model of Loeys‐Dietz syndrome 下载免费PDF全文
Ashvin K. Dewan Ryan E. Tomlinson Stuart Mitchell Brian C. Goh Rachel M. Yung Sarvesh Kumar Eric W. Tan Marie‐Claude Faugere Harry C. Dietz III Thomas L. Clemens Paul D. Sponseller 《Journal of orthopaedic research》2015,33(10):1447-1454
Loeys‐Dietz syndrome (LDS) is a connective tissue disorder characterized by vascular and skeletal abnormalities resembling Marfan syndrome, including a predisposition for pathologic fracture. LDS is caused by heterozygous mutations in the genes encoding transforming growth factor‐β (TGF‐β) type 1 and type 2 receptors. In this study, we characterized the skeletal phenotype of mice carrying a mutation in the TGF‐β type 2 receptor associated with severe LDS in humans. Cortical bone in LDS mice showed significantly reduced tissue area, bone area, and cortical thickness with increased eccentricity. However, no significant differences in trabecular bone volume were observed. Dynamic histomorphometry performed in calcein‐labeled mice showed decreased mineral apposition rates in cortical and trabecular bone with normal numbers of osteoblasts and osteoclasts. Mechanical testing of femurs by three‐point bending revealed reduced femoral strength and fracture resistance. In vitro, osteoblasts from LDS mice demonstrated increased mineralization with enhanced expression of osteoblast differentiation markers compared with control cells. These changes were associated with impaired TGF‐β1–induced Smad2 and Erk1/2 phosphorylation and upregulated TGF‐β1 ligand mRNA expression, compatible with G357W as a loss‐of‐function mutation in the TGF‐β type 2 receptor. Paradoxically, phosphorylated Smad2/3 in cortical osteocytes measured by immunohistochemistry was increased relative to controls, possibly suggesting the cross‐activation of TGF‐β–related receptors. The skeletal phenotype observed in the LDS mouse closely resembles the principal structural features of bone in humans with LDS and establishes this mouse as a valid in vivo model for further investigation of TGF‐β receptor signaling in bone. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1447–1454, 2015. 相似文献
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Ketamine‐related cystitis is characterized by ketamine‐induced urinary frequency and bladder pain. It has become a serious problem in recent years. The most typical grossly pathological bladder change with ketamine related cystitis is a contracted bladder and bladder wall thickening. Ulcerative cystitis with an easily bleeding mucosa is a common cystoscopic finding. Microscopically, the urothelium is denuded and is infiltrated by inflammatory cells, such as mast cells and eosinophils. The pathogenesis of ketamine‐related cystitis is complicated and involves many different pathways. Past evidence suggests a direct toxic effect, bladder barrier dysfunction, neurogenic inflammation, immunoglobulin‐E‐mediated inflammation, overexpression of carcinogenic genes, abnormal apoptosis and nitric oxide synthase‐mediated inflammation contribute to the pathogenesis of ketamine‐related cystitis. The first step to managing ketamine‐related cystitis is always asking patients to cease ketamine. Medical treatment might be helpful in patients with early ketamine‐related cystitis and abstinence from ketamine. Several case studies showed that the intravesical installation of hyaluronic acid and intravesical injection of botulinum toxin type A were effective for symptom relief in selected patients. For patients with irreversible pathological change, such as contracted bladder, augmentation enterocystoplasty might be the only solution to increase bladder capacity and relieve intractable bladder pain. 相似文献
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Susan Yung Sing Leung Lui Chris K.F. Ng Andrew Yim Maggie K.M. Ma Kin Yee Lo Chik Cheung Chow Kwok Hong Chu Wai Leung Chak Man Fai Lam Chun Yu Yung Terence P.S. Yip Sunny Wong Colin S.O. Tang Flora S.K. Ng Tak Mao Chan 《Peritoneal dialysis international》2015,35(2):147-158
♦ Background: The impact of a low-glucose peritoneal dialysis (PD) regimen on biomarkers of peritoneal inflammation, fibrosis and membrane integrity remains to be investigated.♦ Methods: In a randomized, prospective study, 80 incident PD patients received either a low-glucose regimen comprising Physioneal (P), Extraneal (E) and Nutrineal (N) (Baxter Healthcare Corporation, Deerfield, IL, USA) (PEN group), or Dianeal (control group) for 12 months, after which both groups continued with Dianeal dialysis for 6 months. Serum and dialysate levels of vascular endothelial growth factor (VEGF), decorin, hepatocyte growth factor (HGF), interleukin-6 (IL-6), macrophage migration inhibitory factor (MIF), hyaluronan (HA), adiponectin, soluble-intracellular adhesion molecule (s-ICAM), vascular cell adhesion molecule-1 (VCAM-1) and P-selectin, and dialysate cancer antigen 125 (CA125), were measured after 12 and 18 months. This paper focuses on results after 12 months, when patients in the PEN group changed to glucose-based PD fluid (PDF).♦ Results: At the end of 12 months, effluent dialysate levels of CA125, decorin, HGF, IL-6, adiponectin and adhesion molecules were significantly higher in the PEN group compared to controls, but all decreased after patients switched to glucose-based PDF. Macrophage migration inhibitory factor level was lower in the PEN group but increased after changing to glucose-based PDF and was similar to controls at 18 months. Serum adiponectin level was higher in the PEN group at 12 months, but was similar in the 2 groups at 18 months. Body weight, residual renal function, ultrafiltration volume and total Kt/V did not differ between both groups. Dialysate-to-plasma creatinine ratio at 4 h was higher in the PEN group at 12 months and remained so after switching to glucose-based PDF.♦ Conclusion: Changes in the biomarkers suggest that the PEN PD regimen may be associated with better preservation of peritoneal membrane integrity and reduced systemic vascular endothelial injury. 相似文献
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Park YH Lee HC Song HG Jung S Ryu SH Shin JW Chung YH Lee YS Suh DJ 《Journal of gastroenterology and hepatology》2003,18(8):927-933
BACKGROUND AND AIM: Recently, antibiotic-resistant microorganisms have been increasingly noted in Korean patients with spontaneous bacterial peritonitis (SBP). The present study investigated the changing pattern of antibiotic resistance and its effects on the clinical outcome in treating SBP. METHODS: The present study retrospectively analyzed 87 episodes of SBP in 1995, 222 in 1998, and 271 in 1999. The isolated microorganisms and their antibiotic susceptibility were compared, and prognostic factors for survival were analyzed. RESULTS: Microorganisms were isolated in 41% of total episodes. The three most frequently isolated organisms were Escherichia coli (48%), Klebsiella pneumoniae (15%), and Aeromonas (8%). Strains that were resistant to cefotaxime in Gram-negative bacilli significantly increased from 7% in 1995 to 28% in 1999, and those to ciprofloxacin increased from 10% to 32%. Treatment failure also increased from 6% to 23%. Combined hepatocellular carcinoma and SBP caused by extended-spectrum beta-lactamase-producing strains were two independent prognostic factors for survival. CONCLUSION: Considering the increase in antibiotic-resistant microorganisms related to SBP, measures to prevent the in-hospital spread of resistant strains and the indiscriminate use of antibiotics should be instituted more stringently. 相似文献