941 resultados para leukocyte adherence
Resumo:
Thesis (Master's)--University of Washington, 2016-06
Resumo:
Thesis (Master's)--University of Washington, 2016-06
Resumo:
Thesis (Ph.D.)--University of Washington, 2016-06
Resumo:
Adhesion of erythrocytes infected with the malaria parasite Plasmodium falciparum to human host receptors is a process associated with severe malarial pathology. A number of in vitro cell lines are available as models for these adhesive processes, including Chinese hamster ovary (CHO) cells which express the placental adhesion receptor chondroitin-4-sulphate (CSA) on their surface. CHO-745 cells, a glycosaminoglycan-negative mutant CHO cell line lacking CSA and other reported P. falciparum adhesion receptors, are often used for recombinant expression of host receptors and for receptor binding studies. In this study we show that P. falciparum-infected erythrocytes can be easily selected for adhesion to an endogenous receptor on the surface of CHO-745 cells, bringing into question the validity of using these cells as a tool for P. falciparum adhesin expression studies. The adhesive interaction between CHO-745 cells and parasitized erythrocytes described here is not mediated by the known P. falciparum adhesion receptors CSA, CD36, or ICAM-1. However, we found that CHO-745-selected parasitized erythrocytes bind normal human IgM and that adhesion to CHO-745 cells is inhibited by protein A in the presence of serum, but not in its absence, indicating a non-specific inhibitory effect. Thus, protein A, which has been used as an inhibitor for a recently described interaction between infected erythrocytes and the placenta, may not be an appropriate in vitro inhibitor for understanding in vivo adhesive interactions. (c) 2005 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
Resumo:
Purpose: This study investigated leukocyte subset responses to moderate-intensity exercise under heat stress, with water (W) or carbohydrate (CHO) drink ingestion. Methods: In repeated trials, 13 soldiers consumed either a W or CHO drink during 3 h of walking at 4.4 km center dot h(-1) with a 5% gradient (15 min rest per hour) under heat stress (35 C and 55% relative humidity). The soldiers wore combat uniforms and carried water bottles and dummy rifles and ammunition, altogether weighing about 11.5 +/- 1.0 kg. Results: Plasma glucose concentration was significantly higher with CHO than W ingestion during exercise (p < 0.01). There were no significant differences between W and CHO conditions in exercise performance, plasma cortisol concentration, heart rate, or core temperature. CHO ingestion significantly moderated the increases in leukocyte (83% in W, 28% in CHO; p < 0.001), monocyte (60% in W, 34% in CHO; p < 0.05), and granulocyte counts (120% in W, 30% in CHO; p < 0.001), but not in lymphocyte count (41% in W, 25% in CHO). Conclusions: The increases in leukocyte and subset counts during moderate-intensity exercise under heat stress may be comparable to those observed during intense exercise in cool conditions. The response of immune cell counts is blunted by CHO intake during moderate-intensity exercise in the heat, and may not occur through the cortisol pathway.
Resumo:
Neisseria gonorrhoeae has well-characterized oxidative stress defense systems that protect against oxidative killing in in vitro assays. In contrast, mutant strains of N. gonorrhoeae lacking oxidative stress defenses are identical to the wild type when tested in an ex vivo survival assay using human polymorphonuclear leukocytes.
Resumo:
Reports on the efficacy of physical activity intervention trials usually only include discussion of the primary outcomes. However, assessing factors such as participant retention, adherence and compliance can assist in the accurate interpretation of the overall impact of a program in terms of reach and appeal. A quasi-randomised trial was carried out to assess and compare retention and adherence rates, and compliance with, a twice weekly resistance training program provided either individually at home or in a group format. Retirement villages (n=6) were assigned to either 'Have A Try' (HAT, home-based) or 'Come Have A Try' (CHAT, group-based); both programs included nine strength and two balance exercises. The program involved a 20-week Intervention Phase a 24-week Maintenance Phase and a 20-week On-going Maintenance Phase. One hundred and nineteen participants (mean age 80 +/- 6 years) were recruited (HAT = 38, CHAT = 81). There was no difference in retention rates at the end of the Intervention Phase, but significantly more HAT than CHAT participants had dropped out of the study (p < 0.01) after the Maintenance Phase and the On-going Maintenance Phase. During the Intervention Phase, over half the HAT and CHAT participants completed >= 75% of the prescribed activity sessions, but adherence was significantly greater in CHAT than HAT during the Maintenance Phase (p < 0.01). Participants in CHAT were significantly more compliant than HAT participants (p < 0.05). Both home- and group-based formats were successful over the short-term, but, in retirement villages, the group program had better adherence and compliance in the longer-term. (c) 2006 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Resumo:
HOCl-modified low-density lipoprotein (LDL) has proinflammatory effects, including induction of inflammatory cytokine production, leukocyte adhesion, and ROS generation, but the components responsible for these effects are not completely understood. HOCl and the myeloperoxidase-H2O2-halide system can modify both protein and lipid moieties of LDL and react with unsaturated phospholipids to form chlorohydrins. We investigated the proinflammatory effects of 1-stearoyl-2-oleoyl-sn-3-glycerophosphocholine (SOPC) chlorohydrin on artery segments and spleen-derived leukocytes from ApoE-/- and C57 Bl/6 mice. Treatment of ApoE-/- artery segments with SOPC chlorohydrin, but not unmodified SOPC, caused increased leukocyte-arterial adhesion in a time- and concentration-dependent manner. This could be prevented by pretreatment of the artery with P-selectin or ICAM-1-blocking antibodies, but not anti-VCAM-1 antibody, and immunohistochemistry showed that P-selectin expression was upregulated. However, chlorohydrin treatment of leukocytes did not increase expression of adhesion molecules LFA-1 or PSGL-1, but caused increased release of ROS from PMA-stimulated leukocytes by a CD36-dependent mechanism. The SOPC chlorohydrin-induced adhesion and ROS generation could be abrogated by pretreatment of the ApoE-/- mice with pravastatin or a nitrated derivative, NCX 6550. These findings suggest that phospholipid chlorohydrins formed in HOCl-treated LDL could contribute to the proinflammatory effects observed for this modified lipoprotein in vitro.
Resumo:
Type 2 diabetes is a complex, progressive endocrine and metabolical disease that typically requires substantial lifestyle changes and multiple medications to lower blood glucose, reduce cardiovascular risk and address comorbidities. Despite an extensive range of available and effective treatments, <50% of patients achieve a glycaemical target of HbA <7.0% and about two-thirds die of premature cardiovascular disease. Adherence to prescribed therapies is an important factor in the management of type 2 diabetes that is often overlooked. Inadequate adherence to oral antidiabetes agents, defined as collecting <80% of prescribed medication, is variously estimated to apply to between 36% and 93% of patients. All studies affirm that a significant proportion of type 2 diabetes patients exhibit poor adherence that will contribute to less than desired control. Identified factors that impede adherence include complex dosing regimens, clinical inertia, safety concerns, socioeconomic issues, ethnicity, patient education and beliefs, social support and polypharmacy. This review explores these factors and potential strategies to improve adherence in patients with type 2 diabetes. © 2011 Blackwell Publishing Ltd.
Resumo:
Background: The Aston Medication Adherence Study was designed to examine non-adherence to prescribed medicines within an inner-city population using general practice (GP) prescribing data. Objective: To examine non-adherence patterns to prescribed oralmedications within three chronic disease states and to compare differences in adherence levels between various patient groups to assist the routine identification of low adherence amongst patients within the Heart of Birmingham teaching Primary Care Trust (HoBtPCT). Setting: Patients within the area covered by HoBtPCT (England) prescribed medication for dyslipidaemia, type-2 diabetes and hypothyroidism, between 2000 and 2010 inclusively. HoBtPCT's population was disproportionately young,with seventy per cent of residents fromBlack and Minority Ethnic groups. Method: Systematic computational analysis of all medication issue data from 76 GP surgeries dichotomised patients into two groups (adherent and non-adherent) for each pharmacotherapeutic agent within the treatment groups. Dichotomised groupings were further analysed by recorded patient demographics to identify predictors of lower adherence levels. Results were compared to an analysis of a self-reportmeasure of adherence [using the Modified Morisky Scale© (MMAS-8)] and clinical value data (cholesterol values) from GP surgery records. Main outcome: Adherence levels for different patient demographics, for patients within specific longterm treatment groups. Results: Analysis within all three groups showed that for patients with the following characteristics, adherence levels were statistically lower than for others; patients: younger than 60 years of age; whose religion is coded as "Islam"; whose ethnicity is coded as one of the Asian groupings or as "Caribbean", "Other Black" and "African"; whose primary language is coded as "Urdu" or "Bengali"; and whose postcodes indicate that they live within the most socioeconomically deprived areas of HoBtPCT. Statistically significant correlations between adherence status and results from the selfreport measure of adherence and of clinical value data analysis were found. Conclusion: Using data fromGP prescribing systems, a computerised tool to calculate individual adherence levels for oral pharmacotherapy for the treatment of diabetes, dyslipidaemia and hypothyroidism has been developed.The tool has been used to establish nonadherence levels within the three treatment groups and the demographic characteristics indicative of lower adherence levels, which in turn will enable the targeting of interventional support within HoBtPCT. © Koninklijke Nederlandse Maatschappij ter bevordering der Pharmacie 2013.
Resumo:
Purpose - To evaluate adherence to prescribed antiepileptic drugs (AEDs) in children with epilepsy using a combination of adherence-assessment methods. Methods - A total of 100 children with epilepsy (≤17 years old) were recruited. Medication adherence was determined via parental and child self-reporting (≥9 years old), medication refill data from general practitioner (GP) prescribing records, and via AED concentrations in dried blood spot (DBS) samples obtained from children at the clinic and via self- or parental-led sampling in children's own homes. The latter were assessed using population pharmacokinetic modeling. Patients were deemed nonadherent if any of these measures were indicative of nonadherence with the prescribed treatment. In addition, beliefs about medicines, parental confidence in seizure management, and the presence of depressed mood in parents were evaluated to examine their association with nonadherence in the participating children. Key Findings - The overall rate of nonadherence in children with epilepsy was 33%. Logistic regression analysis indicated that children with generalized epilepsy (vs. focal epilepsy) were more likely (odds ratio [OR] 4.7, 95% confidence interval [CI] 1.37–15.81) to be classified as nonadherent as were children whose parents have depressed mood (OR 3.6, 95% CI 1.16–11.41). Significance - This is the first study to apply the novel methodology of determining adherence via AED concentrations in clinic and home DBS samples. The present findings show that the latter, with further development, could be a useful approach to adherence assessment when combined with other measures including parent and child self-reporting. Seizure type and parental depressed mood were strongly predictive of nonadherence.