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51.
Lihui Wei Clayton Butcher Yubin Miao Fabio Gallazzi Thomas P Quinn Michael J Welch Jason S Lewis 《Journal of nuclear medicine》2007,48(1):64-72
Early detection of cutaneous melanoma is essential, as prognosis with metastatic melanoma is poor. Previous studies showed that (64)Cu-DOTA-ReCCMSH(Arg(11)) (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N',N'-tetraacetic acid), a cyclic analog of alpha-melanocyte-stimulating hormone (alpha-MSH), has the potential for the detection of malignant melanoma using PET. However, (64)Cu-DOTA-ReCCMSH(Arg(11)) demonstrated high background in nontarget tissues due to the in vivo instability of the Cu-DOTA moiety. CBTE2A (CBTE2A is 4,11-bis(carboxymethyl)-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane) has been shown to be a more stable copper chelate with improved in vivo stability, resulting in an improvement in clearance from nontarget tissues. The goal of this study was to conjugate CBTE2A to the alpha-MSH targeting ReCCMSH(Arg(11)) peptide for labeling to (64)Cu and to investigate whether the increased metal-chelate stability with CBTE2A would improve imaging quality. METHODS: The recyclized peptide CBTE2A-ReCCMSH(Arg(11)) was synthesized using a solid-phase peptide synthesizer followed by rhenium cyclization. In vivo characteristics of (64)Cu-CBTE2A-ReCCMSH(Arg(11)) were examined with small-animal PET and acute biodistribution studies in B16/F1 tumor-bearing mice. RESULTS: Biodistribution studies showed high and rapid receptor-mediated tumor uptake with values similar to those reported for (64)Cu- and (86)Y-labeled DOTA-ReCCMSH(Arg(11)). Nontarget organ concentration for (64)Cu-CBTE2A-ReCCMSH(Arg(11)) was considerably lower than that of the (64)Cu-DOTA analog, resulting in significantly higher tumor-to-nontarget tissue ratios. Compared with (86)Y-DOTA-ReCCMSH(Arg(11)), (64)Cu-CBTE2A-ReCCMSH(Arg(11)) demonstrated increased tumor retention and kidney clearance. Small-animal PET images showed that the tumor could be clearly visualized at all time points (0.5-24 h). CONCLUSION: Our data suggest the superior stability of the (64)Cu-CBTE2A moiety compared with (64)Cu-DOTA, making (64)Cu-CBTE2A-ReCCMSH(Arg(11)) an ideal candidate for the PET of malignant melanoma. 相似文献
52.
Steven N Singh X Charlene Tang Bramah N Singh Paul Dorian Domenic J Reda Crystal L Harris Ross D Fletcher Satish C Sharma J Edwin Atwood Alan K Jacobson H Daniel Lewis Becky Lopez Dennis W Raisch Michael D Ezekowitz 《Journal of the American College of Cardiology》2006,48(4):721-730
OBJECTIVES: The purpose of this study was to determine quality of life (QOL) and exercise performance (EP) in patients with persistent atrial fibrillation (AF) converted to sinus rhythm (SR) compared with those remaining in or reverting to AF. BACKGROUND: Restoration of SR in patients with AF improving QOL and EP remains controversial. METHODS: Patients with persistent AF were randomized double-blind to amiodarone, sotalol, or placebo. Those not achieving SR at day 28 were cardioverted and classified into SR or AF groups at 8 weeks (n = 624) and 1 year (n = 556). The QOL (SF-36), symptom checklist (SCL), specific activity scale (SAS), AF severity scale (AFSS), and EP were assessed. RESULTS: Favorable changes were seen in SR patients at 8 weeks in physical functioning (p < 0.001), physical role limitations (p = 0.03), general health (p = 0.002), and vitality (p < 0.001), and at 1 year in general health (p = 0.007) and social functioning (p = 0.02). Changes in the scores for SCL severity (p = 0.01), functional capacity (p = 0.003), and AFSS symptom burden (p < 0.001) at 8 weeks and in SCL severity (p < 0.01) and AF symptom burden (p < 0.001) at 1 year showed significant improvements in SR versus AF. Symptomatic patients were more likely to have improvement. The EP in SR versus AF was greater from baseline to 8 weeks (p = 0.01) and to 1 year (p = 0.02). The EP correlated with physical functioning and functional capacity except in the AF group at 1 year. CONCLUSIONS: In patients with persistent AF, restoration and maintenance of SR was associated with improvements in QOL measures and EP. There was a strong correlation between QOL measures and EP. 相似文献
53.
Ganapathy A Prasad Kenneth K Wang Lori S Lutzke Jason T Lewis Schuyler O Sanderson Navtej S Buttar Louis M Wong Kee Song Lynn S Borkenhagen Lawrence J Burgart 《Clinical gastroenterology and hepatology》2006,4(2):173-178
BACKGROUND & AIMS: The aim of this study was to assess the validity of frozen section analysis of endoscopic mucosal resection (EMR) specimens from Barrett's esophagus as compared with permanent sections for the detection of neoplasia. Frozen sections help to give immediate feedback for surgical procedures. It has not been determined whether EMR can be adequately interpreted by using frozen sections to aid endoscopists in completely resecting neoplastic lesions. METHODS: EMR specimens from Barrett's esophagus with high-grade dysplasia (HGD) and/or carcinoma were tested by frozen section. Pathologists evaluated EMR specimens for the depth of invasion as well as the appearance of clear margins of resection. The kappa statistic was calculated to assess the degree of agreement between the frozen section and permanent section diagnoses. RESULTS: Twenty-three consecutive patients underwent 30 EMRs with frozen section diagnosis. Frozen section revealed a carcinoma in 7 specimens (23%) and dysplasia in 20 (66%). Permanent sections found carcinoma in 8 specimens (26%), dysplasia in 19 specimens (63%), and normal or nondysplastic Barrett's esophagus in the remainder. The kappa statistic for the depth of invasion of EMR specimens was 0.93 (near perfect agreement). The kappa statistic for the margins of the EMR specimens was 0.80 (excellent agreement). CONCLUSIONS: This study indicated that frozen section analysis of esophageal EMR specimens is valid as compared with permanent section. This technique might allow rapid evaluation about the degree and depth of involvement of cancers. This allows physicians to make decisions regarding further therapy if margins are involved or decrease the use of EMR for histologically benign-appearing lesions. 相似文献
54.
N. J. Cortes B. Afzali D. MacLean D. J. A. Goldsmith H. O'Sullivan J. Bingham D. A. Lewis E. MacMahon C. Y. W. Tong G. Koffman 《American journal of transplantation》2006,6(10):2497-2499
Two organ recipients developed serologic evidence of syphilis infection after renal transplantation from a common deceased donor with a history of treated syphilis. Testing of donor serum for syphilis, which occurred after transplantation, gave results interpreted as consistent with past infection. However, subsequent serologic results in the recipients suggested transmission of infection at transplantation due to active infection of the donor. This may be explained by recent donor re-infection in view of the current syphilis epidemic in the United Kingdom. An initial error in the treatment of recipients further served to highlight unfamiliarity in managing this resurgent infection in the context of organ transplantation. 相似文献
55.
Kevin O'Brien Jean Wright Frances Conboy YeWeng Sanjie Nicky Mandall Stephen Chadwick Ivan Connolly Paul Cook David Birnie Mark Hammond Nigel Harradine David Lewis Cathy McDade Laura Mitchell Alison Murray Julian O'Neill Mike Read Stephen Robinson Dai Roberts-Harry Jonathan Sandler Ian Shaw 《American journal of orthodontics and dentofacial orthopedics》2003,124(3):234-43; quiz 339
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant. 相似文献
56.
levers Carolyn E.; Brown Ronald T.; Lambert Richard G.; Hsu Lewis; Eckman James R. 《Journal of pediatric psychology》1998,23(6):377-388
Objective: To examine moderating effects of family functioningand social support on the relationship of child-related stressorsto caregivers' psychological adaptation in a sample of caregiversof children with a chronic illness. Method: Participants were 67 caregivers of children and adolescentswith sickle cell syndromes. We conducted MANOVAs and subsequenteffect size calculations to determine if family functioningwould buffer the effects of caring for difficult-to-manage childrenwith this illness. Results: Findings supported a moderator effect of family functioningon the association of children's externalizing behavioral problemsto caregivers symptoms of hostility. Greater levels of cohesiveand adaptive family functioning buffered the potential detrimentaleffects of caring for children perceived as hard to manage.No significant associations were obtained between measures ofcaregivers' psychological adaptation and the severity of theirchildren's disease. Conclusions: We make recommendations for family systems interventions,particularly for caregivers of children with behavior problems. 相似文献
57.
The effect associated with the substitution of adenine (A) for guanidine (G) in the promoter region of the apolipoprotein AI gene (?75 bp) with plasma apo AI and high-density lipoprotein (HDL) levels was investigated in the European Atherosclerosis Research Study (EARS). This is a study of healthy offspring (cases) of fathers who had suffered premature myocardial infarction (MI) before age 55 years (n = 565) and age- and sex-matched controls (n = 1,078) from 12 European countries, divided into 5 regions based on geography and language. The frequency of the polymorphism was not significantly different among the regions and the relative frequency of the rare A allele was similar in cases and controls (0.159 vs. 0.142) combining data from all regions. Individuals with one or more A allele had significantly higher plasma apo AI levels (P < 0.05) than individuals homozygous for the G allele. This effect was consistent in all regions. The data were analyzed separately in males and females. In females, those with one or more A allele had significantly higher apo AI levels (P = 0.05) than individuals homozygous for the G allele, and this raising effect of the A allele was greater in cases than controls for both apo AI (5.23% vs. 1.56%) and HDL (4.48% vs. 1.89%). In males, the A allele was associated with higher levels of apo AI and HDL, but the effect was much smaller and the differences did not reach statistical significance. In the females, where the effect of the A allele was strongest, the effect on apo AI associated with genotype was evident in non-smokers, and individuals with one or two A alleles had 3.6% higher apo AI and 3.14% higher HDL levels than individuals homozygous for the G allele. However, in the female smokers the raising effect of the A allele was greatly reduced (0.56%). Thus genetic variation in the promoter region of the apo AI gene is associated with differences in apo AI and HDL levels in healthy individuals throughout Europe, but the effect is modulated by gender, environmental factors such as smoking, and a family history of MI. 相似文献
58.
K C Gopalakrishnan J Lewis 《The Journal of bone and joint surgery. British volume》1990,72(4):554-556
We report seven children in whom traumatic haemarthrosis of the hip had produced lateral subluxation of the femoral head, which is different from the apparent displacement seen in Perthes' disease. In all seven cases, aspiration of the haemarthrosis allowed reduction of the femoral head, and follow-up for a mean of 14 months revealed no evidence of avascular necrosis of the proximal femoral epiphysis. Traumatic haemarthrosis of the hip in children appears to be a clinical entity which can produce femoral head subluxation. Aspiration and traction is the treatment of choice and can cure the condition. 相似文献
59.
Sung-Eun Kong Lewis R. Blennerhassett Kathryn A. Heel Rosalie D. McCauley John C. Hall 《ANZ journal of surgery》1998,68(8):554-561
Ischaemia-reperfusion injury (IRI) is of obvious relevance in situations where there is an interruption of blood supply to the gut, as in vascular surgery, or in the construction of free intestinal grafts. It is now appreciated that IRI also underlies the gut dysfunction that occurs in early shock, sepsis, and trauma. The events that occur during IRI are complex. However, recent advances in cellular biology have started to unravel these underlying processes. The aim of this review is to provide an outline of current knowledge on the mechanisms and consequences of IRI. Initially, IRI appears to be mediated by reactive oxygen metabolites and, at a later stage, by the priming and activation of polymorphonuclear neutrophils (PMN). Ischaemia-reperfusion injury can diminish the barrier function of the gut, and can promote an increase in the leakage of molecules (intestinal permeability) or the passage of microbes across the wall of the bowel (bacterial trans-location). Ischaemia-reperfusion injury to the gut can result in the generation of molecules that may also harm distant tissues. 相似文献
60.
Early Determinants of Adult Metabolic Regulation: Effects of Infant Nutrition on Adult Lipid and Lipoprotein Metabolism 总被引:4,自引:0,他引:4