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Sodeinde O Clarke JL Vulliamy TJ Luzzatto L Mason PJ 《British journal of haematology》2003,122(4):662-668
As the production of NADPH in the pentose phosphate pathway is the main antioxidant defence mechanism available to the Plasmodium falciparum, we have studied the expression of P. falciparum glucose 6-phosphate dehydrogenase-6-phosphogluconolactonase (PfG6PD-6PGL) in G6PD-deficient and normal erythrocyte host cells. Both erythrocytes infected in vitro with a laboratory isolate and erythrocytes from natural human infections were used. Total RNA was prepared from parasites collected from five G6PD-deficient and nine G6PD-normal children in Ibadan, Nigeria, selected after screening 189 rural schoolchildren and 68 clinical malaria patients, and was subjected to Northern blot analysis. The probe was a cDNA fragment of the G6PD domain of the PfG6PD-6PGL gene, with an internal control probe of P. falciparum 18S ribosomal RNA. Quantification was performed using a phosphoimager. Relative to internal control, the abundance of PfG6PD-6PGL mRNA (mean +/- standard deviation) was lower in parasites from G6PD-deficient children (0.29 +/- 0.27) than in G6PD-normal control subjects (0.74 +/- 0.26) (P = 0.014, Mann-Whitney U-test). Although confirmation in a larger study is required, our results suggest a lower relative abundance of PfG6PD-6PGL, and presumably antioxidant activity, in malaria parasites from G6PD-deficient hosts, thus extending the current knowledge of the mechanism of G6PD-deficiency related host protection. 相似文献
64.
We have studied three glycosylphosphatidylinositol (GPI) linked proteins on the erythrocytes of 14 patients with paroxysmal nocturnal haemoglobinuria (PNH). The pattern observed was bimodal in 12 of the patients and trimodal in two. Ten patients had a red cell population with normal CD59 antigen (membrane inhibitor of reactive lysis, MIRL), decay accelerating factor (DAF or CD55) and lymphocyte function-associated antigen (LFA-3 or CD58) and a second abnormal PNH population with absent CD59 antigen, DAF and LFA-3. The other two patients with a bimodal pattern had a red cell population with normal CD59 antigen, DAF and LFA-3 and an abnormal population with reduced, but not absent, CD59 antigen and DAF. The LFA-3 on the abnormal red cells in these two patients appeared to be only slightly reduced. The two patients with a trimodal pattern had a normal population, a population with reduced, not absent, CD59 antigen and DAF, and a population with complete absence of CD59 antigen, DAF and LFA-3. The accuracy of the Ham test in estimating the proportion of red cells with the PNH defect in the two types of PNH was assessed. The case of one patient who appeared to be 'rescued' from severe aplastic anaemia by the development of PNH is described. 相似文献
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Laura M. Perry Leah E. Walsh Ronald Horswell Lucio Miele San Chu Brian Melancon John Lefante Christopher M. Blais James L. Rogers Michael Hoerger 《Journal of pain and symptom management》2021,61(2):342-349.e1
ContextThe comfort of patients with cancer near the end of life (EOL) is often undermined by unnecessary and burdensome treatments. There is a need for more research examining racial disparities in EOL care, especially in regions with a history of racial discrimination.ObjectivesTo examine whether black adults received more burdensome EOL care than white adults in a population-based data set of cancer decedents in Louisiana, a state with a history of slavery and long-standing racial disparities.MethodsThis was a retrospective analysis of EOL care from the Research Action for Health Network (REACHnet), a regional Patient-Centered Outcomes Research Institute-funded database. The sample consisted of 875 white and 415 black patients with metastatic cancer who died in Louisiana from 2011 to 2017. We used logistic regression to examine whether race was associated with five indicators of burdensome care in the last 30 days of life: chemotherapy use, inpatient hospitalization, intensive care unit admission, emergency department (ED) admission, and mechanical ventilation.ResultsMost patients (85.0%) received at least one indicator of burdensome care: hospitalization (76.5%), intensive care unit admission (44.1%), chemotherapy (29.1%), mechanical ventilation (23.0%), and ED admission (18.3%). Odds ratios (ORs) indicated that black individuals were more likely than white individuals to be hospitalized (OR = 1.66; 95% CI = 1.21–2.28; P = 0.002) or admitted to the ED (OR = 1.57; 95% CI = 1.16–2.13; P = 0.004) during their last month of life.ConclusionFindings have implications for informing health care decision making near the EOL for patients, families, and clinicians, especially in regions with a history of racial discrimination and disparities. 相似文献
66.
Fabrizia Veronesi Lucio Nisoli Manuela Diaferia Roberto Falcini Emanuele Ficola Daniela Piergili Fioretti 《Parasitology research》2013,112(6):2137-2142
A blind, randomised, controlled, multicentric field trial was conducted to assess the influence of a metaphylactic treatment with an oral solution of toltrazuril on some reproductive parameters of Italian Fresian heifers during the first 18–20 months of life. For this goal 40 calves were selected from two dairy farms and randomly divided into two homogeneous groups: MTol, treated with toltrazuril and NegC, left untreated. The calves were clinically and coprologically examined over the entire study period. The body condition scores, the body weights and the age at the first service were recorded and compared between the two groups, in addition to some other reproductive parameters including number of pregnancies, average service per pregnancy, conception rate, conception rate at first service and post first service conception rate. The analysis of the results showed that the metaphylactic treatment with toltrazuril influenced positively the average age of the first service (MTol 461.4 days versus NegC 485.45 days), the overall conception rate (MTol 95 % versus NegC 85 %), the success at first (MTol 60 % versus NegC 45 %) and second (MTol 75 % versus NegC 45 %) services and, consequently, the mean number of services to be carried out for each animal (MTol 1.4?±?0.6 versus NegC 1.6?±?0.79). Furthermore, the results confirmed that toltrazuril treatment, applied in accordance with the epidemiological aspects of each farm, is highly efficacious in persistent reduction of oocyst excretions with particular reference to Eimeria zuernii, Eimeria bovis, considered to be mainly responsible for clinical coccidiosis. 相似文献
67.
Vriz Olga Palatini Paolo Mos Lucio AlSergani Hani Vendramin Igor Livi Ugolino Antonini-Canterin Francesco Magne Julien 《The international journal of cardiovascular imaging》2021,37(5):1659-1668
The International Journal of Cardiovascular Imaging - Aortic valve stenosis (AS) shares similarities with the atherosclerotic process but little is known about the effect of the mechanical... 相似文献
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Vanessa dos Santos Grandinétti Eduardo Foschini Miranda Douglas Scott Johnson Paulo Roberto Vicente de Paiva Shaiane Silva Tomazoni Adriane Aver Vanin Gianna Móes Albuquerque-Pontes Lucio Frigo Rodrigo Labat Marcos Paulo de Tarso Camillo de Carvalho Ernesto Cesar Pinto Leal-Junior 《Lasers in medical science》2015,30(5):1575-1581
70.
Patients with paroxysmal nocturnal hemoglobinuria have a high frequency of peripheral-blood T cells expressing activating isoforms of inhibiting superfamily receptors 总被引:4,自引:2,他引:4
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Poggi A Negrini S Zocchi MR Massaro AM Garbarino L Lastraioli S Gargiulo L Luzzatto L Notaro R 《Blood》2005,106(7):2399-2408
Patients with paroxysmal nocturnal hemoglobinuria (PNH) have a large clonal population of blood cells deriving from hematopoietic stem cells (HSCs) deficient in glycosylphosphatidylinositol (GPI)-anchored surface molecules. A current model postulates that PNH arises through negative selection against normal HSCs exerted by autoreactive T cells, whereas PNH HSCs escape damage. We have investigated the inhibitory receptor superfamily (IRS) system in 13 patients with PNH. We found a slight increase in the proportion of T cells expressing IRS. In contrast to what applies to healthy donors, the engagement of IRS molecules on T cells from patients with PNH elicited a powerful cytolytic activity in a redirected killing assay, indicating that these IRSs belong to the activating type. This was confirmed by clonal analysis: 50% of IRS+ T-cell clones in patients with PNH were of the activating type, while only 5% were of the activating type in healthy donors. Moreover, the ligation of IRS induces (1) production of tumor necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) and (2) brisk cytolytic activity against cells bearing appropriate IRS counter-ligands. In addition, these IRS+ T cells show natural killer (NK)-like cytolytic activity to which GPI- cells were less sensitive than GPI+ cells. Thus, T cells with NK-like features, expressing the activating isoforms of IRS, may include effector cells involved in the pathogenesis of PNH. 相似文献