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91.
MG Myers M Godwin M Dawes A Kiss SW Tobe J Kaczorowski 《Journal of hypertension》2012,30(10):1937-1941
OBJECTIVES:: To determine the prevalence of masked hypertension [normal office blood pressure (BP) with high awake ambulatory BP] using automated office BP (AOBP) or conventional manual office BP (MOBP) measurement in routine clinical practice. METHODS:: The prevalence of masked hypertension was evaluated on three consecutive visits during a median 6 months period in patients with systolic hypertension randomized to management with AOBP (n?=?140) or continued conventional MOBP (n?=?112) in routine primary care practice. AOBP was recorded using the automated BpTRU device with the patient resting alone in a quiet examining room. All patients underwent 24-h ambulatory BP monitoring. RESULTS:: The prevalence of masked hypertension on any one of three visits calculated using only SBP varied between 12 and 17% in the AOBP group compared with 19 and 22 % in the MOBP group. Masked hypertension was present on both of the first two visits in 7 and 12% and on all three visits in 6 and 7% of AOBP and MOBP patients, respectively. The prevalence for masked hypertension based upon both SBP and DBP was similar being 11-15% for AOBP and 19-20% for MOBP patients on single visits, but decreased to 6 and 10% when readings from the first two visits were used and to 4 and 6% when all three visits were used for the AOBP and MOBP groups, respectively. CONCLUSION:: The prevalence of masked hypertension is lower with AOBP compared with MOBP. The number of patients with masked hypertension decreases if the criteria for having this condition need to be met on multiple visits. 相似文献
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Lívia Budai Nóra Kaszás Pál Gróf Katalin Lenti Katayoon Maghami István Antal Imre Klebovich Ilona Petrikovics Marianna Budai 《Scientia pharmaceutica》2013,81(4):1151-1166
Developments in nanotechnology and in the formulation of liposomal systems provide the opportunity for cosmetic dermatology to design novel delivery systems. Determination of their physico-chemical parameters has importance when developing a nano-delivery system. The present study highlights some technological aspects/characteristics of liposomes formulated from egg or soy lecithins for topical use. Alterations in the pH, viscosity, surface tension, and microscopic/macroscopic appearance of these vesicular systems were investigated. The chemical composition of the two types of lecithin was checked by mass spectrometry. Caffeine, as a model molecule, was encapsulated into multilamellar vesicles prepared from the two types of lecithin: then zeta potential, membrane fluidity, and encapsulation efficiency were compared. According to our observations, samples prepared from the two lecithins altered the pH in opposite directions: egg lecithin increased it while soy lecithin decreased it with increased lipid concentration. Our EPR spectroscopic results showed that the binding of caffeine did not change the membrane fluidity in the temperature range of possible topical use (measured between 2 and 50 °C). Combining our results on encapsulation efficiency for caffeine (about 30% for both lecithins) with those on membrane fluidity data, we concluded that the interaction of caffeine with the liposomal membrane does not change the rotational motion of the lipid molecules close to the head group region. In conclusion, topical use of egg lecithin for liposomal formulations can be preferred if there are no differences in the physico-chemical properties due to the encapsulated drugs, because the physiological effects of egg lecithin vesicles on skin are significantly better than that of soy lecithin liposomes. 相似文献
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Charles L Bennett Benjamin Kim Anaadriana Zakarija Nicholas Bandarenko Dilip K Pandey Charlie G Buffie June M McKoy Amul D Tevar John F Cursio Paul R Yarnold Hau C Kwaan Davide De Masi Ravindra Sarode Thomas J Raife Joseph E Kiss Dennis W Raisch Charles Davidson J Evan Sadler Thomas L Ortel X Long Zheng Seiji Kato Masanori Matsumoto Masahito Uemura Yoshihiro Fujimura 《Journal of the American College of Cardiology》2007,50(12):1138-1143
OBJECTIVES: We sought to describe clinical and laboratory findings for a large cohort of patients with thienopyridine-associated thrombotic thrombocytopenic purpura (TTP). BACKGROUND: The thienopyridine derivatives, ticlopidine and clopidogrel, are the 2 most common drugs associated with TTP in databases maintained by the U.S. Food and Drug Administration (FDA). METHODS: Clinical reports of TTP associated with clopidogrel and ticlopidine were identified from medical records, published case reports, and FDA case reports (n = 128). Duration of thienopyridine exposure, clinical and laboratory findings, and survival were recorded. ADAMTS13 activity (n = 39) and inhibitor (n = 30) were measured for a subset of individuals. RESULTS: Compared with clopidogrel-associated TTP cases (n = 35), ticlopidine-associated TTP cases (n = 93) were more likely to have received more than 2 weeks of drug (90% vs. 26%), to be severely thrombocytopenic (84% vs. 60%), and to have normal renal function (72% vs. 45%) (p < 0.01 for each). Compared with TTP patients with ADAMTS13 activity >15% (n = 13), TTP patients with severely deficient ADAMTS13 activity (n = 26) were more likely to have received ticlopidine (92.3% vs. 46.2%, p < 0.003). Among patients who developed TTP >2 weeks after thienopyridine, therapeutic plasma exchange (TPE) increased likelihood of survival (84% vs. 38%, p < 0.05). Among patients who developed TTP within 2 weeks of starting thienopyridines, survival was 77% with TPE and 78% without. CONCLUSIONS: Thrombotic thrombocytopenic purpura is a rare complication of thienopyridine treatment. This drug toxicity appears to occur by 2 different mechanistic pathways, characterized primarily by time of onset before versus after 2 weeks of thienopyridine administration. If TTP occurs after 2 weeks of ticlopidine or clopidogrel therapy, therapeutic plasma exchange must be promptly instituted to enhance likelihood of survival. 相似文献
98.
Estimating genome conservation between crop and model legume species 总被引:31,自引:0,他引:31
Choi HK Mun JH Kim DJ Zhu H Baek JM Mudge J Roe B Ellis N Doyle J Kiss GB Young ND Cook DR 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(43):15289-15294
Legumes are simultaneously one of the largest families of crop plants and a cornerstone in the biological nitrogen cycle. We combined molecular and phylogenetic analyses to evaluate genome conservation both within and between the two major clades of crop legumes. Genetic mapping of orthologous genes identifies broad conservation of genome macrostructure, especially within the galegoid legumes, while also highlighting inferred chromosomal rearrangements that may underlie the variation in chromosome number between these species. As a complement to comparative genetic mapping, we compared sequenced regions of the model legume Medicago truncatula with those of the diploid Lotus japonicus and the polyploid Glycine max. High conservation was observed between the genomes of M. truncatula and L. japonicus, whereas lower levels of conservation were evident between M. truncatula and G. max. In all cases, conserved genome microstructure was punctuated by significant structural divergence, including frequent insertion/deletion of individual genes or groups of genes and lineage-specific expansion/contraction of gene families. These results suggest that comparative mapping may have considerable utility for basic and applied research in the legumes, although its predictive value is likely to be tempered by phylogenetic distance and genome duplication. 相似文献
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Effects of estrogen and medroxyprogesterone acetate on subpopulations of triglyceride-rich lipoproteins and high-density lipoproteins 总被引:1,自引:0,他引:1
Lamon-Fava S Posfai B Asztalos BF Horvath KV Dallal GE Schaefer EJ 《Metabolism: clinical and experimental》2003,52(10):1330-1336
Hormonal replacement therapy (HRT) in postmenopausal women has been shown to increase both triglyceride (TG) and high-density lipoprotein (HDL) cholesterol levels. To better understand the effects of conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA), the 2 most commonly prescribed hormones in HRT, on the different subpopulations of TG-rich and HDL lipoproteins, we conducted a placebo-controlled, double-blind, randomized, crossover study consisting of 3 different phases in 14 postmenopausal women. The 3 phases, each 8-week long, included: (1) placebo, (2) CEE 0.625 mg/d, and (3) CEE 0.625 mg/d and MPA 2.5 mg/d. Slight and statistically nonsignificant elevations in TG levels were observed during the CEE treatment. While very-low-density lipoprotein (VLDL) cholesterol levels were not significantly affected by CEE and CEE + MPA, both HRT treatments lowered remnant lipoprotein (RLP) cholesterol (-14% and -37%, respectively). Compared with placebo, CEE caused a significant increase in HDL, HDL(2), apolipoprotein (apo) A-I, LpAI, alpha1, and prealpha1 levels (12%, 27%, 17%, 26%, 60%, and 102%, respectively). The combination therapy blunted the CEE effect on all HDL parameters, resulting in HDL, HDL(2), and LpAI levels being no longer significantly different from placebo. Apo A-I levels and alpha1, and prealpha1 levels were still significantly higher than placebo (+11%, +50%, and +112%, respectively). These results indicate that HRT has beneficial effects on RLP levels and that, while the estrogen component of HRT has a beneficial effect on the HDL subpopulations mostly associated with coronary heart disease (CHD) protection, MPA partially inhibits this effect. 相似文献