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81.
Clinical correlations of diffusion and perfusion lesion volumes in acute ischemic stroke 总被引:3,自引:0,他引:3
Baird AE Lövblad KO Dashe JF Connor A Burzynski C Schlaug G Straroselskaya I Edelman RR Warach S 《Cerebrovascular diseases (Basel, Switzerland)》2000,10(6):441-448
The aim of this study was to describe the clinico-radiological correlations of magnetic resonance (MR) perfusion and diffusion-weighted imaging (DWI) abnormalities in ischemic stroke. Eighteen patients had undergone MR imaging and clinical evaluation within 24 h of symptom onset and at or after 7 days. During the first 24 h the volume of perfusion abnormality (measured on the relative mean transit time map) was larger than the DWI lesion in 12/18 patients. In 6/18 patients the DWI lesion volume was larger. Acutely (<24 h) all lesion volumes showed a significant correlation with acute clinical severity measured by the National Institutes of Health Stroke Scale score. The correlations of the hypoperfusion volume (rho = 0.86, p = 0.0001) and the volume 'tissue at risk' (larger than the DWI and perfusion lesion volumes, rho = 0.86, p = 0. 0001) with acute clinical severity were slightly higher than for the DWI lesion volume (rho = 0.76, p = 0.0001). The difference between the volume of tissue at risk (acutely) and the infarct on follow-up T(2)-weighted imaging correlated significantly with change in clinical severity from acute to chronic time points (rho = 0.72, p = 0.001). Such clinico-radiological relationships may support the use of DWI and perfusion MR in decisions concerning the administration and evaluation of stroke therapies. 相似文献
82.
Evaluation of low-dose endotoxin administration during pregnancy as a model of preeclampsia 总被引:1,自引:0,他引:1
Sakawi Y Tarpey M Chen YF Calhoun DA Connor MG Chestnut DH Parks DA 《Anesthesiology》2000,93(6):1446-1455
BACKGROUND: Recent evidence implicates nitric oxide (*NO) in the pathogenesis of preeclampsia. The authors tested the hypothesis that administration of low-dose endotoxin to pregnant rats mimics the signs of preeclampsia in humans and that *NO and *NO-derived species play a role in that animal model. METHODS: Endotoxin was infused at doses of 1, 2 and 10 microg/kg over 1 h to rats on day 14 of pregnancy. Mean arterial pressure, urinary protein, urinary and plasma nitrite plus nitrate (NO2- + NO3-) concentrations, and platelet count were measured before and after the endotoxin infusion. In another group of pregnant rats, the nitric oxide synthase inhibitor L-nitroarginine methyl ester (L-NAME) was administered in drinking water at a dose of 3 mg x kg(-1) x d(-1) starting on day 7 of pregnancy. Endotoxin was then infused at 10 microg/kg on day 14 of pregnancy. Kidneys and uteroplacental units were examined histologically and analyzed immunohistochemically for 3-nitrotyrosine. RESULTS: Endotoxin administration at doses of 2 and 10 microg/kg caused proteinuria and thrombocytopenia in pregnant rats, but did not result in hypertension. Urinary NO2- + NO3- concentration, reflective of tissue *NO production rates, was significantly elevated in pregnant rats that received endotoxin at 10 microg/kg. Ingestion of L-NAME caused hypertension. Tissues from pregnant rats treated with L-NAME, endotoxin at 10 microg/kg, and a combination of L-NAME and endotoxin had increased 3-nitrotyrosine immunoreactivity. CONCLUSION: Nitric oxide either directly or through secondary species plays a significant role in the biochemical and physiologic changes that occur in a rodent model of endotoxin-induced injury. 相似文献
83.
Thaer S. Alomar Khalid Mahmood Simon O’Connor Keith Robson Harminder S. Dua 《International ophthalmology》2013,33(5):561-565
Crystalline corneal deposits have been well reported in individual cases of lymphoproliferative disorders associated with hyper-gammaglobulinemia, hence called ‘Crystalline Paraproteinemic Keratopathy’. This is the first report of corneal deposits in a case of localised conjunctival B-cell Lymphoma without paraproteinaemia/hyper-gammaglobulinemia, hence called ‘Presumed Paraproteinic Crystalline Keratopathy’. 相似文献
84.
85.
Andrew Holden Andrew A. Hill Brendan Buckley Brigid Connor David Semple Stephen Merrilees Emma Marsh Aws Alfahad Ram Iyer 《Journal of vascular and interventional radiology : JVIR》2019,30(1):61-68
Purpose
A prospective, single-center, single-arm feasibility study evaluated procedural and short-term performance of the Advance Enforcer 35 focal-force percutaneous transluminal angioplasty (PTA) balloon catheter in treating stenoses of mature native arteriovenous (AV) hemodialysis access circuits.Materials and Methods
Twenty-eight patients undergoing treatment for stenosis of a mature native AV hemodialysis access circuit were enrolled at a single institution. Angiographic assessments of the study lesion were required at baseline and after the procedure. Adjunctive procedures for significant residual stenosis were permitted, and patients had clinical and imaging follow-up for as long as 6 months.Results
Treatment with the study balloon was effective in reducing the average percent diameter stenosis of the treated lesion from 66.3% (range, 43.8%–93.3%) before the procedure to 23.7% (range, ?6.7% to 51.4%) after the procedure. The average inflation pressure required was 12.3 atm. Only 1 patient required an adjunctive procedure, and all patients could resume normal dialysis following the study procedure. At 3 months, 62.0% of study lesions remained patent, and the 6-month patency rate was 25.1%. Two adverse events associated with the study procedure were reported: access-site hematoma and forearm pain (3.6% each).Conclusions
The results demonstrate safety of the study balloon in treating AV access stenosis. Nominal-diameter angioplasty was achieved at relatively low pressure in most study patients without the use of adjunctive procedures, and resumption of normal dialysis was achieved for all patients. 相似文献86.
87.
88.
Ann C. McKee Nigel J. Cairns Dennis W. Dickson Rebecca D. Folkerth C. Dirk Keene Irene Litvan Daniel P. Perl Thor D. Stein Jean-Paul Vonsattel William Stewart Yorghos Tripodis John F. Crary Kevin F. Bieniek Kristen Dams-O’Connor Victor E. Alvarez Wayne A. Gordon the TBI/CTE group 《Acta neuropathologica》2016,131(1):75-86
89.
Andrew M. Thompson Patrick D. OConnor Vanessa Yardley Louis Maes Delphine Launay Stephanie Braillard Eric Chatelain Baojie Wan Scott G. Franzblau Zhenkun Ma Christopher B. Cooper William A. Denny 《ACS medicinal chemistry letters》2021,12(2):275
Antitubercular 7-substituted 2-nitroimidazo[2,1-b][1,3]oxazines were previously shown to exhibit potent antileishmanial and antitrypanosomal activities, culminating in a new clinical investigational drug for visceral leishmaniasis (DNDI-0690). To offset development risks, we continued to seek further leads with divergent candidate profiles, especially analogues possessing greater aqueous solubility. Starting from an efficacious monoaryl derivative, replacement of the side chain ether linkage by novel amine, amide, and urea functionality was first explored; the former substitution was well-tolerated in vitro and in vivo but elicited marginal alterations to solubility (except through a less stable benzylamine), whereas the latter groups resulted in significant solubility improvements (up to 53-fold) but an antileishmanial potency reduction of at least 10-fold. Ultimately, we discovered that O-carbamate 66 offered a more optimal balance of increased solubility, suitable metabolic stability, excellent oral bioavailability (100%), and strong in vivo efficacy in a visceral leishmaniasis mouse model (97% parasite load reduction at 25 mg/kg). 相似文献
90.
Donald S. Colbourn Jennifer E. Amengual Changchun Deng Ahmed Sawas Owen A. O’Connor 《Expert review of anticancer therapy》2016,16(2):199-210
Mantle Cell lymphoma is a heterogeneous malignancy that has different subtypes with variable levels of aggressiveness. Research on the pathobiology of this disease is helping us understand the etiology for this heterogeneity and has the potential to guide future therapeutic options. The availability of the Ki67 proliferation index and the use of the MIPI score can help determine which of the numerous therapeutic options might be utilized. Minimal Residual Disease testing can act as a guide as to the potential benefit of maintenance therapy. This article discusses the current standard of care for Mantle Cell lymphoma and our current understanding of the pathobiology of the disease leading to strategies to improve patient outcomes with some of the newer targeted agents. 相似文献