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991.
Glycophorin C is the receptor for the Plasmodium falciparum erythrocyte binding ligand PfEBP-2 (baebl) 总被引:7,自引:1,他引:7
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We report in this paper that glycophorin C (GPC) is the receptor for PfEBP-2 (baebl, EBA-140), the newly identified erythrocyte binding ligand of Plasmodium falciparum. PfEBP-2 is a member of the Duffy binding-like erythrocyte binding protein (DBL-EBP) family. Although several reports have been published characterizing PfEBP-2, the identity of its erythrocytic receptor was still unknown. Using a combination of enzymatically treated red blood cells (RBCs) and rare, variant RBCs lacking different surface proteins, we have shown that PfEBP-2 does not bind to cells lacking GPC. Additionally, we found that PfEBP-2 binds differentially to variants of GPC lacking exon 2 or exon 3, and determined that the binding domain on GPC is potentially restricted to amino acid residues 14 through 22 within exon 2. Thus PfEBP-2 is involved in a sialic acid-dependent pathway of invasion, which does not involve glycophorin A or glycophorin B and represents a novel route of entry into the RBCs. 相似文献
992.
Impaired fasting glucose (IFG) like impaired glucose tolerance (IGT) has increased risk of progressing to diabetes mellitus (DM). The aim of the study was to evaluate prevalance of IGT and type 2 DM with oral glucose tolerance test (OGTT) in Turkish patients who had fasting glucose of 110 and 125 mg/dl. Hundred and forty-eight (67.3%) women and 72 (32.7%) men (30-65 years old with mean age of 51.3 +/- 8.7 year) who had fasting glucose range 110-125 mg/dl were evaluated with OGTT. Seventy-two patients had IGT (32.8%), 74 (33.6%) patients had type 2 diabetes and 74 (33.6%) patients had normal glucose tolerance (NGT). Mean fasting glucose and insulin levels were higher in the IGT group than in the NGT group. Mean level of total cholesterol was higher in DM than that in NGT and IGT groups. Mean triglyceride (TG) (P = 0.476), high-density lipoprotein (HDL) (P = 0.594), low-density lipoprotein (LDL) (P = 0.612), Apoproteine A (P = 0.876), Apoproteine B (P = 0.518), uric acid (P = 0.948) and ferritin (P = 0.314) were found higher in diabetic patients. Lipoproteine a (P = 0.083), fibrinogen (P = 0.175) and hsCRP (P = 0.621) levels were higher in IGT. Mean HOMA S% levels of NGT, IGT and DM were found to be 65.0 +/- 13.0%, 60.9 +/- 16.0% and 50.1 +/- 11.1%, respectively. HOMA B% levels were measured to be 80.4 +/- 29.1% in NGT, 85.3 +/- 14.59% in IGT and 60.1 +/- 10.1% in DM. Significant difference was found between IFG and DM (P = 0.043) groups. The prevalences of diabetes and IGT were found to be 33.63 and 32.7% in IFG, respectively. 相似文献
993.
994.
Ezrin regulates NHE3 translocation and activation after Na+-glucose cotransport 总被引:3,自引:0,他引:3
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Zhao H Shiue H Palkon S Wang Y Cullinan P Burkhardt JK Musch MW Chang EB Turner JR 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(25):9485-9490
Initiation of Na(+)-glucose cotransport in intestinal epithelial cells leads to activation of the apical Na(+)-H(+) exchanger NHE3 and subsequent increases in cytoplasmic pH (pH(i)). This process requires activation of p38 mitogen-activated protein (MAP) kinase, but additional signaling intermediates have not been identified. One candidate is the cytoskeletal linker protein ezrin, which interacts with NHE3 via specific regulatory proteins. The data show that initiation of Na(+)-glucose cotransport resulted in rapid increases in both apical membrane-associated NHE3 and cytoskeletal-associated ezrin and occurred in parallel with ezrin phosphorylation at threonine 567. Phosphorylation at this site is known to activate ezrin and increase its association with actin. Consistent with a central role for ezrin activation in this NHE3 regulation, an N-terminal dominant negative ezrin construct inhibited both NHE3 recruitment and pH(i) increases after Na(+)-glucose cotransport. Ezrin phosphorylation occurred in parallel with p38 MAP kinase activation, and the latter proceeded normally in cells expressing dominant negative ezrin. In contrast, inhibition of p38 MAP kinase prevented increases in ezrin phosphorylation after initiation of Na(+)-glucose cotransport. Thus, ezrin phosphorylation after Na(+)-glucose cotransport requires p38 MAP kinase activity, but p38 MAP kinase activation does not require ezrin function. These data describe a specific role for ezrin in the coordinate regulation of Na(+)-glucose cotransport and Na(+)-H(+) exchange. Intact ezrin function is necessary for NHE3 recruitment to the apical membrane and NHE3-dependent pH(i) increases triggered by Na(+)-glucose cotransport. The data also define a pathway of p38 MAP kinase-dependent ezrin activation. 相似文献
995.
Sara K. Tedeschi Joan M. Bathon Jon T. Giles Tzu‐Chieh Lin Kazuki Yoshida Daniel H. Solomon 《Arthritis care & research》2018,70(3):327-332
Objective
To assess whether more frequent fish consumption is associated with lower rheumatoid arthritis (RA) disease activity scores among participants in an RA cohort.Methods
We conducted a cross‐sectional analysis using baseline data from participants in the Evaluation of Subclinical Cardiovascular Disease and Predictors of Events in Rheumatoid Arthritis cohort study. Frequency of fish consumption was assessed by a baseline food frequency questionnaire assessing usual diet in the past year. Multivariable, total energy–adjusted linear regression models provided effect estimates and 95% confidence intervals (95% CIs) for frequency of fish consumption (i.e., never to <1 time/month, 1 time/month to <1 time/week, 1 time/week, and ≥2 times/week) on baseline Disease Activity Score in 28 joints (DAS28) using the C‐reactive protein (CRP) level. We also estimated the difference in DAS28‐CRP associated with increasing fish consumption by 1 serving per week.Results
Among 176 participants, the median DAS28‐CRP score was 3.5 (interquartile range 2.9–4.3). In an adjusted linear regression model, subjects consuming fish ≥2 times/week had a significantly lower DAS28‐CRP compared with subjects who ate fish never to <1 time/month (difference ?0.49 [95% CI ?0.97, ?0.02]). For each additional serving of fish per week, DAS28‐CRP was significantly reduced by 0.18 (95% CI ?0.35, ?0.004).Conclusion
Our findings suggest that higher intake of fish may be associated with lower disease activity in RA patients.996.
997.
Simone Saibeni Anna Lecchi Gianmichele Meucci Marco Cattaneo Liliana Tagliabue Emanuele Rondonotti Sara Formenti Roberto De Franchis Maurizio Vecchi 《Clinical gastroenterology and hepatology》2005,3(6):574-580
BACKGROUND & AIMS: Hyperhomocysteinemia, a risk factor for thrombosis, recurrent miscarriages, and osteoporosis, might derive from acquired folate and vitamin B 12 deficiencies and from a C677T mutation in methylene-tetrahydrofolate reductase (MTHFR) gene. Undiagnosed gluten-sensitive enteropathy (GSE) is associated with vitamin deficiencies, osteoporosis, and recurrent miscarriages. We evaluated the prevalence and the risk factors for hyperhomocysteinemia in patients with newly diagnosed GSE. METHODS: In this prospective study performed in a tertiary care setting, 40 consecutive subjects with newly diagnosed GSE were evaluated for homocysteine, folate, and vitamin B 12 levels and for C677T polymorphism. One hundred twenty sex- and age-matched healthy control subjects were studied. Nonparametric tests and multiple regression analysis were used to evaluate the risk factors in inducing hyperhomocysteinemia in the GSE population. RESULTS: Hyperhomocysteinemia was more frequent in GSE patients than in control subjects (8/40, 20.0% vs 7/120, 5.8%) (relative risk, 3.4; 95% confidence interval, 1.3-8.9), as well as folate deficiency (17/40, 42.5% vs 10/120, 8.3%) (relative risk, 5.1; 95% confidence interval, 2.5-10.2). Multiple regression analysis showed that folate and B 12 levels were independently and inversely associated with homocysteine levels, whereas homozygosity for the MTHFR thermolabile variant was not. The prevalence of MTHFR variant in GSE population was not different from that reported in racially comparable control groups. Gluten-free diet was able to normalize folate, vitamin B 12 , and homocysteine levels. CONCLUSIONS: Hyperhomocysteinemia is frequent in newly diagnosed GSE. Vitamin deficiencies caused by malabsorption are the most important determinants of this condition. Hyperhomocysteinemia might contribute to the occurrence of common complications of undiagnosed GSE. 相似文献
998.
Francesco Zanon Lina Marcantoni Enrico Baracca Gianni Pastore Giuseppina Giau Gianluca Rigatelli Daniela Lanza Claudio Picariello Silvio Aggio Sara Giatti Marco Zuin Loris Roncon Domenico Pacetta Franco Noventa Frits W. Prinzen 《Journal of interventional cardiac electrophysiology》2018,52(1):31-37
Purpose
Late cure after a previously failed ablation of ventricular arrhythmias (VAs) is a relatively common phenomenon. The present study sought to delineate the incidence and electrophysiological characteristics of late cure in idiopathic VA patients.Methods
Totally, 45 idiopathic VA cases (mean age 44?±?18 years, 27 males) either failed acutely or recurred within 12 h were enrolled in this study. Based on intensive clinical observations in the acute period, 19 (42%) patients demonstrated late cure in the first week after the procedure.Results
The late cure patients had significantly better acute and cumulative ablation effects during the procedure than did those without a late cure. Additionally, they had a prediction that originated from the right ventricular outflow tract, aortic-mitral continuum, and left summit area relative to other sites (13/18 vs 6/27, p?<?0.01). In a median follow-up of 24 [14, 46] months, 7/19 (37%) patients had their VAs recurred. The late cure group had significantly more patients cured at long-term follow-up than those without (12/19 vs 0/26, p?<?0.01). A cutoff value of the “time to eliminate VAs” >?7.0 s was able to predict a long-term recurrence of the VAs with 62.5% sensitivity and 85.7% specificity.Conclusions
The late cure of VAs occurs in more than one third of patients who have a seemingly unsuccessful ablation session, which is clustered in the first week after the procedure. However, long-term recurrence of VAs occurred in 37% of the late cure patients, emphasizing the importance of long-term follow-up.999.
WHERE THERE'S SMOKING,THERE'S FIRE: THE EFFECTS OF SMOKING POLICIES ON THE INCIDENCE OF FIRES IN THE USA
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Sara Markowitz 《Health economics》2014,23(11):1353-1373
Fires and burns are among the leading causes of unintentional death in the USA. Most of these deaths occur in residences, and cigarettes are a primary cause. In this paper, I explore the relationship between smoking, cigarette policies, and fires. As smoking rates decline, there are fewer opportunities for fires; however, the magnitude of any reduction is in question. Using a state‐level panel, I find that increases in cigarette prices are associated with fewer residential fires and deaths. However, laws regulating indoor smoking are associated with more fires; in particular, restaurant and bar smoking bans are associated with an increase in fires at eating and drinking establishments. This increase is important given the growing popularity of smoking bans in the USA and around the world. As workplaces, schools, and businesses ban smoking and remove ashtrays, smokers who continue to smoke are left without safe options for disposal of cigarettes, leading to more opportunities for fires to start. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
1000.
Joanne C. Sandberg Jennifer W. Talton Sara A. Quandt Haiying Chen Maria Weir Walkiria R. Doumani Arjun B. Chatterjee Thomas A. Arcury 《Journal of immigrant and minority health / Center for Minority Public Health》2014,16(2):265-272
Although poor sleep quality and associated sleep disorders are associated with increased risk of job injury and multiple mental and physical health problems, scant research has examined sleep quality among Latino farmworkers. Interviews were conducted with 371 male Latino farmworkers working in North Carolina during the 2010 agricultural season. Data on housing quality and sleep quality were collected. Access to air conditioning was significantly and positively associated with good sleep quality. This association remained when other housing characteristics and individual health indicators were controlled. Good sleep quality was associated with low levels of pain, depression, and anxiety. Poor sleep quality among Latino farmworkers was associated with poorer indicators of health. One important indicator of housing quality, air conditioning, was associated with better sleep quality. Further research is required to delineate how to improve the adequacy of farmworker housing to improve sleep quality and other health indicators. 相似文献