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11.
The expression of human leukocyte antigen-G on trophoblasts abolishes the growth-suppressing effect of interleukin-2 towards them 总被引:9,自引:0,他引:9
Hamai Y Fujii T Yamashita T Miki A Hyodo H Kozuma S Geraghty DE Taketani Y 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,41(2):153-158
PROBLEM: We have shown the attenuated human leukocyte antigen (HLA)-G expression on trophoblasts and an aberrant expression of interleukin (IL)-2, a cytotoxic cytokine, in decidual tissue in preeclampsia, where deteriorated trophoblastic invasion into decidual layers may constitute a crucial pathogenesis. We hypothesized that the absence of HLA-G might make trophoblasts susceptible to compromise by IL-2. METHOD OF STUDY: We analyzed the growth of HLA-G-negative and positive cell lines, all of which possessed IL-2 receptors, in the culture with or without IL-2 supplementation. RESULTS: The proliferation of HLA-G positive trophoblastic cell lines (BeWo and JEG-3) was not influenced by the addition of IL-2, whereas a HLA-G-negative trophoblastic cell line (JAR) exhibited significantly decreased proliferation when cultured with IL-2. Interestingly, the transfection of JAR cells with HLA-G completely eliminates the growth-inhibitory effect of IL-2. CONCLUSION: The expression of HLA-G may commit trophoblasts to evade cell damage by IL-2, which may be relevant to maternal tolerance of the fetus during pregnancy and its derangement as exemplified by preeclampsia. 相似文献
12.
Symptomatic peripheral arterial disease: the value of a validated questionnaire and a clinical decision rule
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Bianca LW Bendermacher Joep AW Teijink Edith M Willigendael Marie-Louise Bartelink Harry R Büller Ron JG Peters Jelis Boiten Machteld Langenberg Martin H Prins 《The British journal of general practice》2006,56(533):932-937
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease. 相似文献
13.
Internal quality assurance in a clinical virology laboratory. I. Internal quality assessment.
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J J Gray T G Wreghitt T A McKee P McIntyre C E Roth D J Smith G Sutehall G Higgins R Geraghty R Whetstone et al. 《Journal of clinical pathology》1995,48(2):168-173
AIMS--In April 1991 an internal quality assessment scheme (IQAS) was introduced into the virology section of the Clinical Microbiology and Public Health Laboratory, Cambridge. The IQAS was established to identify recurring technical and procedural problems, to check the adequacy of current techniques, and to calculate the frequency of errors. METHODS--Between April 1991 and December 1993, 715 anonymous clinical serum samples were submitted to the laboratory to test 3245 individual procedures of diagnostic viral serology. RESULTS--A total of 485 (14.9%) procedural and 61 (1.9%) technical discrepancies were observed, the technical discrepancies mainly being recorded in complement fixation tests. Twenty two (0.7% of total procedures) of the technical discrepancies were diagnostically significant. CONCLUSIONS--Evaluation criteria developed with the introduction of IQAS to viral serology, and technical and procedural discrepancies are assessed. As yet, IQAS has not been introduced to other sections of the diagnostic virology laboratory (virus isolation, electron microscopy, immunofluorescence, and enzyme linked immunosorbent assays for viral and chlamydial antigens). 相似文献
14.
Internal quality assurance in a clinical virology laboratory. II. Internal quality control.
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J J Gray T G Wreghitt T A McKee P McIntyre C E Roth D J Smith G Sutehall G Higgins R Geraghty R Whetstone et al. 《Journal of clinical pathology》1995,48(3):198-202
AIMS--In April 1991 additional quality control procedures were introduced into the virology section of the Clinical Microbiology and Public Health Laboratory, Cambridge. Internal quality control (IQC) samples were gradually included in the serological assays performed in the laboratory and supplemented kit controls and standard sera. METHODS--From April 1991 to December 1993, 2421 IQC procedures were carried out with reference sera. RESULTS--The IQC samples were evaluated according to the Westgard rules. Violations were recorded in 60 of 1808 (3.3%) controls and were highest in the IQC samples of complement fixation tests (25/312 (8%) of controls submitted for complement fixation tests). CONCLUSIONS--The inclusion of IQC samples in the serological assays performed in the laboratory has highlighted batch to batch variation in commercial assays. The setting of acceptable limits for the IQC samples has increased confidence in the validity of assay results. 相似文献
15.
Murray Thomson Eng Cheng Chan Joanne Davies John Falconer Gemma Madsen Simon Geraghty Roger Smith 《Neuroscience letters》1990,110(3):343-348
It is not certain which protein kinase (A, C or both) is involved in the acute phase of β-endorphin (β-EP) release stimulated in the corticotrope by vasopressin (VP) and corticotropin-releasing factor (CRF). We have employed an isolated ovine anterior pituitary cell superfusion system to determine the dynamic effects of forskolin, a protein kinase A (PKA) stimulator, and phorbol 12-myristate 13-acetate (PMA), a protein kinase C (PKC) activator. Both secretagogues stimulated β-EP release within 5 min and therefore both PKA and PKC are potential mediators of the acute phase of hormonal stimulation of the corticotrope. Pretreatment with PMA specifically desensitized the pituitary cell columns to subsequent PMA exposure while not significantly altering sensitivity to forskolin or 50 mM KCl. 相似文献
16.
Maternal and Child Health Journal - Colonization with Group B Streptococcus in pregnancy is a major risk factor for neonatal infection. Universal screening for maternal streptococcal colonization... 相似文献
17.
Geraghty ME 《Nephrology news & issues》2000,14(4):12-3, 42-4, 54
The use of complementary and adjunctive therapy has been steadily increasing in the U.S. since the 1960s. This can be attributed to several factors, particularly because over 80 million "baby boomers" are embracing alternative medicine as a way to enhance their medical care. The perceived coldness and remoteness of conventional medicine; the entanglement of managed care in red tape; continued emphasis on "natural" which supposedly connotes "better," as well as the popularity of vegetarian practices have also contributed to the general population's increasing involvement in alternative medicine. In 1999, 40% of all Americans sought alternative medical treatment, outpacing visits to conventional primary care physicians. 相似文献
18.
19.
PT Clayton M Doig S Ghafari C Meaney C Taylor JV Leonard M Morris AW Johnson 《Archives of disease in childhood》1998,79(2):109-115
OBJECTIVE: To establish criteria for the diagnosis of medium chain acyl-CoA dehydrogenase (MCAD) deficiency in the UK population using a method in which carnitine species eluted from blood spots are butylated and analysed by electrospray ionisation tandem mass spectrometry (ESI-MS/MS). DESIGN: Four groups were studied: (1) 35 children, aged 4 days to 16.2 years, with proven MCAD deficiency (mostly homozygous for the A985G mutation, none receiving carnitine supplements); (2) 2168 control children; (3) 482 neonates; and (4) 15 MCAD heterozygotes. RESULTS: All patients with MCAD deficiency had an octanoylcarnitine concentration ([C8-Cn]) > 0.38 microM and no accumulation of carnitine species > C10 or < C6. Among the patients with MCAD deficiency, the [C8-Cn] was significantly lower in children > 10 weeks old and in children with carnitine depletion (free carnitine < 20 microM). Neonatal blood spots from patients with MCAD deficiency had a [C8-Cn] > 1.5 microM, whereas in heterozygotes and other normal neonates the [C8-Cn] was < 1.0 microM. In contrast, the blood spot [C8-Cn] in eight of 27 patients with MCAD deficiency > 10 weeks old fell within the same range as five of 15 MCAD heterozygotes (0.38-1.0 microM). However, the free carnitine concentrations were reduced (< 20 microM) in the patients with MCAD deficiency but normal in the heterozygotes. CONCLUSIONS: Criteria for the diagnosis of MCAD deficiency using ESI-MS/MS must take account of age and carnitine depletion. If screening is undertaken at 7-10 days, the number of false positive and negative results should be negligible. Because there have been no instances of death or neurological damage following diagnosis of MCAD deficiency in our patient group, a strong case can be made for neonatal screening for MCAD deficiency in the UK. 相似文献
20.
Sheela R Geraghty Susan M Pinney Gopalan Sethuraman Ashwini Roy-Chaudhury Heidi J Kalkwarf 《Ambulatory Pediatrics》2004,4(3):226-231
OBJECTIVE: Over 3% of infants born annually in the United States are from a multiple gestation pregnancy, yet there is little data published about the feeding practices of their mothers. The objectives of this study were to determine and compare the rates of breast milk feeding of mothers of multiples and mothers of singletons. METHODS: Stratified random sampling (n = 686) on the basis of plurality of pregnancy and gestational age at delivery was performed on a 1999 birth certificate database in the greater Cincinnati area. We collected information about infant feeding during the first 6 months of life using a retrospective, self-administered questionnaire and phone interview from mothers of term singletons (TS), preterm singletons (PS), term multiples (TM), and preterm multiples (PM). Data were analyzed using chi-square and logistic or multiple regression. RESULTS: We obtained feeding information from 346 mothers (n = 81 TS, 80 PS, 90 TM, and 95 PM). By 3 days postpartum, PM provided breast milk less often than all other groups: TS = 69%, PS = 66%, TM = 73%, PM = 57% (P =.035). Among mothers who initiated breast milk feeding, the geometric mean duration of at least some breast milk feeding was significantly shorter for PM than for all other groups: TS = 23 weeks, PS = 19 weeks, TM = 24 weeks, and PM = 12 weeks (P =.002). CONCLUSIONS: Further evaluation of the potential causes for the lower breast milk feeding rates among PM is needed to develop effective intervention strategies and increase the number of preterm multiple gestation infants receiving breast milk. 相似文献