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41.
The ring-infected erythrocyte surface antigen of Plasmodium falciparum associates with spectrin in the erythrocyte membrane. 总被引:7,自引:0,他引:7
The malaria parasite Plasmodium falciparum synthesises a protein, RESA, which associates with the membrane of newly invaded erythrocytes. Using spent supernatants from P. falciparum growing in culture as a source of soluble RESA we have developed an assay to examine the characteristics of RESA binding to the erythrocyte membrane in vitro. RESA associated with the Triton X-100 insoluble proteins on the inner face of the host erythrocyte membrane but did not bind to the outer surface of intact erythrocytes. Other proteins present in culture supernatants did not bind to the erythrocyte membrane. RESA was co-sedimented with the ternary complex formed between actin, spectrin and band 4.1 and co-precipitated with spectrin precipitated with anti-spectrin antibodies. The extent of association between RESA and the inner face of the erythrocyte membrane was reduced by the inclusion of excess purified spectrin in the assay. Thus, RESA appears to be associated with spectrin in the erythrocyte membrane skeleton. 相似文献
42.
George J Demakis Flora Hammond Allison Knotts Douglas B Cooper Pamelia Clement Jan Kennedy Tom Sawyer 《Archives of clinical neuropsychology》2007,22(1):123-130
This study examined the Personality Assessment Inventory (PAI) in 95 individuals who had suffered a traumatic brain injury (TBI). Participants were recruited from a rehabilitation hospital (n=60) and a military hospital (n=35); despite differences in demographics and injury characteristics groups did not differ on any of the clinical scales and were thus combined. In the combined group, the highest mean clinical scale elevations were on Somatic Complaints, Depression, and Borderline Features and the most common configural profiles, based on cluster analysis, were Cluster 1 (no prominent elevations), Cluster 6 (social isolation and confused thinking), and Cluster 2 (depression and withdrawal). Factor analysis indicated a robust three-factor solution that accounted for 74.86 percent of the variance and was similar to findings from the psychiatric and non-psychiatric populations in the standardization sample. The above findings are compared with the previous literature on psychopathology in TBI, particularly in regards to the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), as well as previous psychometric research on the PAI. 相似文献
43.
Neuropsychological Deficit and Academic Performance in Children and Adolescents Following Traumatic Brain Injury 总被引:1,自引:1,他引:1
Kinsella Glynda; Prior Margot; Sawyer Michael; Murtagh Douglas; Eisenmajer Richard; Anderson Vicki; Bryan Doug; Klug Geoffrey 《Journal of pediatric psychology》1995,20(6):753-767
Evaluated the utility of neuropsychological testing in predictingacademic outcome in children 1 year following traumatic braininjury (TBI). Fifty-one schoolage children who were admittedto hospital after TBI were assessed with a battery of neuropsychologicalmeasures at 3 months postinjury. Academic achievement was assessedat 3 and 12 months postinjury. The neuropsychological batteryincluded intelligence testing and measures of memory, learning,and speed of information processing. Academic outcome was assessedin terms of post-TBI changes in reading, spelling, and arithmetic;changes in teacher ratings of school performance; and changein school placement. According to logistic regression analysis,change in placement from regular to special education at 1-yearpost-TBI was predicted by injury severity and by neuropsychologicalperformance at 3 months post-TBI. Findings suggest that neuropsychologicaltesting is useful in identifying children with special educationalneeds subsequent to TBI. 相似文献
44.
The Wnt pathway, epithelial-stromal interactions, and malignant progression in phyllodes tumours 总被引:3,自引:0,他引:3
Sawyer EJ Hanby AM Rowan AJ Gillett CE Thomas RE Poulsom R Lakhani SR Ellis IO Ellis P Tomlinson IP 《The Journal of pathology》2002,196(4):437-444
In a previous study of phyllodes tumours, it has been shown that both the stroma and the epithelium can exhibit distinct molecular changes, suggesting that both are part of the neoplastic process. In view of this finding, it was decided to study stromal-epithelial interactions in these tumours by examining the Wnt-APC-beta-catenin pathway. Beta-catenin and cyclin D1 immunohistochemistry was performed on 119 phyllodes tumours. Eighty-six (72%) showed stromal nuclear beta-catenin localization and in 57% the staining was moderate or strong; however, of the eight malignant tumours in the series, seven showed absent or weak nuclear staining (p<0.025). In no tumour was nuclear beta-catenin staining seen in the epithelial component. Moderate or strong stromal cyclin D1 staining correlated with nuclear stromal beta-catenin staining (p<0.05). Forty-five of the tumours, including two malignant lesions, were screened for beta-catenin exon 3 mutations using SSCP and sequencing, but none was found. Loss of heterozygosity (LOH) of the marker D5S346 was used to infer APC mutation, but only one (benign) tumour showed LOH. Wnt2 and Wnt5a mRNA was localized by in situ hybridization in 13 cases (three malignant) chosen to reflect the different beta-catenin staining patterns. There was an association between strong nuclear beta-catenin staining of stromal cells and epithelial Wnt5a expression (p<0.0015). These data suggest that stromal proliferation in benign phyllodes tumours relies on abnormalities in the Wnt pathway which result not from mutation, but from Wnt5a expression in the epithelium. In the progression to malignancy, the stromal proliferation appears to become independent of the Wnt pathway and, presumably, of the epithelial component of these tumours. 相似文献
45.
Lymphokine-activated killer (LAK) cells can be focused at sites of tumor growth by products of macrophage activation 总被引:1,自引:0,他引:1
R J Migliori S A Gruber M D Sawyer R Hoffman A Ochoa F H Bach R L Simmons 《Surgery》1987,102(2):155-162
Successful adoptive cancer immunotherapy presumably depends on the accumulation of tumoricidal leukocytes at the sites of tumor growth. Large numbers of lymphokine-activated killer (LAK) cells can be generated in vitro by growth in high concentrations of interleukin-2 (IL-2), but relatively few arrive at the tumor site after intravenous injection. We hypothesize that the delivery of LAK cells to tumor sites may be augmented by previously demonstrated lymphocyte-recruiting factors, including activated macrophage products such as interleukin-1 (IL-1) and tumor necrosis factor. 111Indium-labeled LAK cells were injected intravenously into syngeneic mice bearing the macrophage activator endotoxin (LPS) in one hind footpad, and saline solution was injected into the contralateral footpad. Significantly more activity was recovered from the LPS-bearing footpad at all times during a 96-hour period. Recombinant IL-1 also attracted more LAK cells after injection into tumor-free hind footpads. Furthermore, LAK cells preferentially homed to hind footpads that were bearing 3-day established sarcomas after intralesional injections of LPS, IL-1, or tumor necrosis factor when compared with contralateral tumor-bearing footpads injected with saline solution alone. In preliminary experiments, mice with hind-footpad tumors appeared to survive longer after combined systemic IL-2 and LAK therapy if intralesional LPS was administered. These studies demonstrate that macrophage activation factors that have been shown capable of attracting circulating normal lymphocytes can also effectively attract LAK cells from the circulation. By the stimulation of macrophages at the sites of tumor growth, more LAK cells can be attracted. It is hoped that by "focusing" the migration of LAK cells to tumors, LAK cells and IL-2 would effect tumor regression more efficiently and with less toxicity. 相似文献
46.
Gemma M. J. Taylor Katherine Sawyer David Kessler Marcus R. Munaf Paul Aveyard Alison Shaw 《Health expectations》2021,24(2):411
BackgroundTobacco smoking rates are significantly higher in people with common mental illness compared to those without. Smoking cessation treatment could be offered as part of usual outpatient psychological care, but currently is not.ObjectiveTo understand patient and health care professionals'' views about integrating smoking cessation treatment into outpatient psychological services for common mental illness.DesignQualitative in‐depth interviews, with thematic analysis.ParticipantsEleven Improving Access to Psychological Therapies (IAPT) psychological wellbeing practitioners (PWPs), six IAPT patients, and six stop smoking advisors were recruited from English smoking cessation, and IAPT services.ResultsPatients reported psychological benefits from smoking, and also described smoking as a form of self‐harm. Stop smoking advisors displayed therapeutic pessimism and stigmatizing attitudes towards helping people with mental illness to quit smoking. PWPs have positive attitudes towards smoking cessation treatment for people with common mental illness. PWPs and patients accept evidence that smoking tobacco may harm mental health, and quitting might benefit mental health. PWPs report expertise in helping people with common mental illness to make behavioural changes in the face of mood disturbances and low motivation. PWPs felt confident in offering smoking cessation treatments to patients, but suggested a caseload reduction may be required to deliver smoking cessation support in IAPT.ConclusionsIAPT appears to be a natural environment for smoking cessation treatment. PWPs may need additional training, and a caseload reduction. Integration of smoking cessation treatment into IAPT services should be tested in a pilot and feasibility study.Patient or public contributionService users and members of the public were involved in study design and interpretation of data. 相似文献
47.
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49.
K L Wickens J Crane T J Kemp S J Lewis W J D'Souza G M Sawyer M L Stone S J Tohill J C Kennedy T M Slater N E Pearce 《Epidemiology (Cambridge, Mass.)》1999,10(6):699-705
We conducted a prevalence case-control study to investigate the relation between family composition, infection, and development of asthma at age 7-9 years. Potential cases (399) and controls (398) were selected from the Wellington, NZ, arm of the International Study of Asthma and Allergies in Childhood, a population-based prevalence study. Further screening questions restricted cases to children with a diagnosis of asthma and current medication use (N = 233) and restricted controls to children without a history of wheezing and no diagnosis of asthma (N = 241). After controlling for confounders (including infections, atopy, and socioeconomic status), family size was strongly related to asthma. Having no siblings [prevalence odds ratio (POR) = 2.51; 95% confidence interval (CI) = 1.05-6.01] or one sibling (POR = 1.86; 95% CI = 1.14-3.03) was associated with an increased risk of asthma compared with having more than one sibling. Parent-reported rubeola infection (and possibly other similar viral exanthems) was independently associated with a decreased risk of asthma (POR = 0.48; 95% CI = 0.27-0.83), but reported pertussis infection (POR = 1.57; 95% CI = 0.58-4.24) and day care attendance in the first year of life (POR = 1.81; 95% CI = 0.93-3.51) were not strongly associated with increased risks of asthma. 相似文献
50.
Pyle MA Jasinevicius TR Lalumandier JA Kohrs KJ Sawyer DR 《General dentistry》1999,47(5):500-3; quiz 504-5
The occurrence of retromolar foramina (RMF) was examined in a sample of dry skulls (African American n = 249; Causcasian n = 226) to consider the potential clinical impact. A prevalence rate of 7.8% of RMF was found. There were no statistical differences based on race or gender. The prevalence may contribute to the explanation of a portion of inferior alveolar nerve block failures and provide insight into potential implications of surgery in the posterior mandible. 相似文献