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71.
Secretory IgA and IgM antibodies to E. coli O and poliovirus type I antigens occur in amniotic fluid,meconium and saliva from newborns. A neonatal immune response without antigenic exposure: a result of anti-idiotypic induction? 总被引:3,自引:2,他引:3
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Antibodies to E. coli O-antigens and poliovirus type I antigen as well as total SIgA were analysed using enzyme-linked immunosorbent assay (ELISA), in amniotic fluid and in meconium, urine and saliva from neonates. Secretory IgA and IgM antibodies to E. coli and poliovirus antigens were found in saliva as well as in most meconium samples taken during the first day of life. SIgA could be quantified in all types of samples including amniotic fluid. The finding of secretory IgA and IgM antibodies to E. coli and poliovirus type I antigens in early samples from an infant of a hypogammaglobulinaemic mother, given regular intravenous (i.v.) immunoglobulin prophylaxis, but still lacking IgA and IgM antibodies, supports a fetal origin for at least part of the secretory antibodies detected in the different samples. Since it is unlikely that the fetus has been exposed to poliovirus, which is rare in Sweden, it is hypothesized that the stimulus inducing the SIgA and IgM antibodies found in the neonate could be anti-idiotypic antibodies from the mother. 相似文献
72.
Shakir YA Samsioe G Nerbrand C Lidfeldt J;Women's Health in the Lund Area study 《Menopause (New York, N.Y.)》2004,11(5):549-555
OBJECTIVE: To delineate the influence of hormone therapy (HT) on features of metabolic syndrome with special reference to the composition and mode of administration of three specific HT regimens, all containing estradiol (E2) + norethisterone. DESIGN: The Women's Health in the Lund Area project screened all women (n = 10,766), born between 1935 and 1945. Complete data were obtained from 6,917 women. Those at or above defined cutoff limits were considered positively screened (n = 3,593) for metabolic syndrome. All of them were invited to undergo an oral glucose tolerance test; 2,923 women accepted. After excluding 200 women with impaired fasting glucose, 2,723 women were included in the present analysis. Serum lipids were determined by conventional standard methods at the department of clinical chemistry of Lund University Hospital. RESULTS: According to World Health Organization criteria, 2,123 women had normal glucose tolerance and 600 women had impaired glucose tolerance (IGT). IGT was less common (P = 0.001) among users of a transdermal patch [CYC-TRANS; E2 50 microg + norethisterone acetate (NETA) 250microg] compared with the two-combined oral regimen [CON-O (continuous oral E2 2 mg + NETA 1 mg) + CYC-O (sequential oral E2 2 mg + NETA 1 mg)]. Furthermore, IGT was more common among CON-O users when compared with either the CYC-O + CYC-TRANS group (P = 0.002) or the CYC-TRANS only group (P = 0.001). There were no significant differences between CYC-O versus CYC-TRANS or CON-O. Serum levels of total cholesterol were higher in the CYC-TRANS group than in the combined CON-O + CYC-O group (P < 0.05); they also were higher (P = 0.05) when comparing the CYC-O + CYC-TRANS versus CON-O as well as higher in CYC-TRANS versus CON-O (P < 0.05). Serum high-density lipoprotein cholesterol levels were higher in the CYC-O (P = 0.001), CYC-TRANS (P < 0.05), and the CYC-O + CYC-TRANS (P = 0.001) groups when compared with the CON-O users. There were no differences in the mean age, blood pressure (systolic and diastolic), body mass index, waste-hip ratio, or the rate of cigarette and alcohol consumption between the different hormone regimens. CONCLUSION: The risk of having a pathological glucose load was lower in transdermal versus oral users of HT. Transdermal HT could be regarded as first-line treatment in women at risk of developing diabetes. 相似文献
73.
I. Jurna K. -H. Carlsson W. Kömen D. Bonke 《Journal of molecular medicine (Berlin, Germany)》1990,68(2):129-135
Summary Nociceptive activity was elicited in neurones of the thalamus by supramaximal electrical stimulation of afferent C fibres in the sural nerve of rats under urethane anesthesia. The fixed combination of vitamin B1, B6, B12 (Neurobion®) as well as of vitamin B6 administered by i.p. injection dose-dependently reduced the evoked nociceptive activity. The ED50 of Neurobion® is 4.6 ml/kg (at 100 min after injection) and that of vitamin B6 is 189mg/kg (at 90 min after injection). The minimum effective doses of Neurobion® and vitamin B6 are 0.5 ml/kg and 40 mg/kg, respectively. When Neurobion® or vitamin B6 were given at their minimum effective doses, and the minimum effective doses of morphine (0.025 mg/kg) or paracetamol (5 mg/kg) were injected i.v. 80 min later, i.e., when the maximum effect of higher doses of Neurobion® or vitamin B6was about to develop, no supraadditive effect developed. It is concluded that the antinociceptive effect caused by a single injection of Neurobion® is largely due to vitamin B6. Vitamin B12 may contribute to this effect, whereas vitamin B1 alone exhibited only a slight effect on nociception. Moreover, it appears that Neurobion® produces its antinociceptive effect after a single injection and after repeated administration during several days by different mechanisms so that the effect of analgesic agents is not enhanced following a single injection of Neurobion® but may be enhanced after repeated administration of the compound. 相似文献
74.
The University of Missouri-Kansas City (UMKC) School of Medicine is a public medical school that opened in 1971 in response to a need to train more physicians in Missouri. As a six-year, integrated, combined-degree program leading to the baccalaureate and medical degrees, the school offers an innovative, nontraditional approach to medical education. In the past 35 years, UMKC has graduated over 2,400 physicians who are successful according to outcomes measures used at other medical schools. With recent interest in reforming medical education to prepare physicians for a changing world, a review of alternative models may be especially instructive.UMKC's academic plan offers a blueprint for the curriculum plan and governance of the school. The plan is built on four hallmarks: (1) a combined baccalaureate/MD program, (2) early exposure to clinical medicine, (3) small-group learning through the docent system, and (4) a continuing ambulatory care clinic experience for four years.This article catalogs the results of this plan including student, faculty, and graduates' perceptions of and satisfaction with the school's educational approach, students' achievement on licensing examinations and in the residency match, graduates' performance in residency programs, and their subsequent career patterns. The authors also discuss lessons learned and adjustments made in response to local needs in the context of a changing environment in education, health care, and health care delivery while continually improving the school's nontraditional approach to medical education. These include changes in basic and clinical science instruction, student assessment, faculty development, and funding and governance. 相似文献
75.
José M Echevarría Ana Avellón Gesa Jonas Michael Hausmann Angela Vockel Hans-Peter Kapprell 《Journal of clinical virology》2006,35(4):368-372
BACKGROUND AND OBJECTIVES: Compliance with current regulations regarding the prevention of hepatitis C virus (HCV) transmission in the blood transfusion setting requires the use of sensitive assays for HCV antibody (anti-HCV) detection, which should, ideally, identify any donor having had prior contact with the virus. Therefore, low-level anti-HCV positive blood units should be detected by the screening assays, even those reflecting a past and resolved infection. To assess the sensitivity of two versions of an automated chemiluminescent microparticle immunoassay (CMIA) for anti-HCV screening (ARCHITECT Anti-HCV), 113 single serum samples containing low levels of anti-HCV, assessed by two immunoblot tests, were selected from 3686 samples received for confirmation of HCV infection by a reference laboratory over a 2-year period. MATERIALS AND METHODS: The panel included 17 samples with HCV RNA detected by the polymerase chain reaction (PCR) and 96 PCR negative samples with either positive or indeterminate (anti-Core and anti-NS3 alone) results by immunoblot. RESULTS: All but 13 specimens (100/113, 88.5%) were detected by the current version of the ARCHITECT Anti-HCV assay and 10 additional samples (110/113, 97.3%) tested positive in a modified version of the test. CONCLUSION: The results showed that the modification introduced in the ARCHITECT Anti-HCV assay achieves a significant sensitivity improvement including samples with low-level anti-HCV which are either PCR positive or negative. 相似文献
76.
Andersson J Sanchez J Ekdahl KN Elgue G Nilsson B Larsson R 《Journal of biomedical materials research. Part A》2003,67(2):458-466
Contact between blood and a biomaterial surface takes place in many applications and is known to activate the coagulation and complement systems. Heparin surface coatings have been shown to reduce blood activation upon contact with artificial surfaces. To establish the optimal heparin surface concentration, blood was incubated in a tubing loop model at 37 degrees C. The tubing was coated with different surface concentrations of heparin and rotated at three different velocities. We demonstrate that the blood compatibility of a surface with regard to coagulation, complement, and platelet activation can be improved by increasing the heparin surface concentration in the 6-12 pmol antithrombin/cm2 concentration interval. The binding of factor H is not influenced by the increased heparin surface concentration, suggesting that this factor is not the primary regulator of complement on heparin surfaces. In addition, the heparin coating has no effect on the complement activation that occurs on gas surfaces in extracorporeal circuits. 相似文献
77.
Radiation dose measurements with alanine/agarose gel and thin alanine films around a 192Ir brachytherapy source,using ESR spectroscopy 总被引:6,自引:0,他引:6
Olsson S Bergstrand ES Carlsson AK Hole EO Lund E 《Physics in medicine and biology》2002,47(8):1333-1356
Alanine/agarose gel and alanine films in stacks have been used for measurements of absorbed dose around an HDR 192Ir source in a vaginal cylinder-applicator, with and without a 180 degrees tungsten shield. The gel and the films were analysed by means of ESR spectroscopy and calibrated against an ion chamber in a 4 MV photon beam to obtain absolute dose values. The gel serves as both dosimeter and phantom material, and the thin (130 microm) films are used to achieve an improved spatial resolution in the dose estimations. Experimental values were compared with Monte Carlo simulations using two different codes. Results from the measurements generally agree with the simulations to within 5%, for both the alanine/agarose gel and the alanine films. 相似文献
78.
c-Myc is essential for vasculogenesis and angiogenesis during development and tumor progression 总被引:13,自引:0,他引:13
Baudino TA McKay C Pendeville-Samain H Nilsson JA Maclean KH White EL Davis AC Ihle JN Cleveland JL 《Genes & development》2002,16(19):2530-2543
c-Myc promotes cell growth and transformation by ill-defined mechanisms. c-myc(-/-) mice die by embryonic day 10.5 (E10.5) with defects in growth and in cardiac and neural development. Here we report that the lethality of c-myc(-/-) embryos is also associated with profound defects in vasculogenesis and primitive erythropoiesis. Furthermore, c-myc(-/-) embryonic stem (ES) and yolk sac cells are compromised in their differentiative and growth potential. These defects are intrinsic to c-Myc, and are in part associated with a requirement for c-Myc for the expression of vascular endothelial growth factor (VEGF), as VEGF can partially rescue these defects. However, c-Myc is also required for the proper expression of other angiogenic factors in ES and yolk sac cells, including angiopoietin-2, and the angiogenic inhibitors thrombospondin-1 and angiopoietin-1. Finally, c-myc(-/-) ES cells are dramatically impaired in their ability to form tumors in immune-compromised mice, and the small tumors that sometimes develop are poorly vascularized. Therefore, c-Myc function is also necessary for the angiogenic switch that is indispensable for the progression and metastasis of tumors. These findings support the model wherein c-Myc promotes cell growth and transformation, as well as vascular and hematopoietic development, by functioning as a master regulator of angiogenic factors. 相似文献
79.
Hippocampal GABAergic interneurons show diverse molecular and morphological properties. The functional significance of this diversity for information processing is poorly understood. Here we show that cholecystokinin (CCK)-expressing interneurons in rat dentate gyrus release GABA in a highly asynchronous manner, in contrast to parvalbumin (PV) interneurons. With a gamma-frequency burst of ten action potentials, the ratio of asynchronous to synchronous release is 3:1 in CCK interneurons but is 1:5 in parvalbumin interneurons. N-type channels trigger synchronous and asynchronous release in CCK interneuron synapses, whereas P/Q-type Ca(2+) channels mediate release at PV interneuron synapses. Effects of Ca(2+) chelators suggest that both a long-lasting presynaptic Ca(2+) transient and a large distance between Ca(2+) source and sensor of exocytosis contribute to the higher ratio of asynchronous to synchronous release in CCK interneuron synapses. Asynchronous release occurs at physiological temperature and with behaviorally relevant stimulation patterns, thus generating long-lasting inhibition in the brain. 相似文献
80.
Gene profiling reveals increased expression of uteroglobin and other anti-inflammatory genes in glucocorticoid-treated nasal polyps 总被引:3,自引:0,他引:3
Benson M Carlsson L Adner M Jernås M Rudemo M Sjögren A Svensson PA Uddman R Cardell LO 《The Journal of allergy and clinical immunology》2004,113(6):58-1143
BACKGROUND: Treatment with local glucocorticoids (GCs) decreases symptoms and the size of nasal polyps. This might depend on the downregulation of proinflammatory genes, as well as the upregulation of anti-inflammatory genes. OBJECTIVE: We sought to identify GC-regulated anti-inflammatory genes in nasal polyps. METHODS: Affymetrix DNA microarrays were used to analyze the expression of 22,283 genes in 4 nasal polyps before and after local treatment with fluticasone (400 microg/d). Expression of uteroglobin and mammaglobin B was analyzed with real-time PCR in 6 nasal polyps and in nasal biopsy specimens from 6 healthy control subjects. RESULTS: Two hundred three genes had changed in expression in treated polyps, and 139 had known functions: 54 genes were downregulated, and 85 were upregulated. Genes associated with inflammation constituted the largest single functional group. These genes affected key steps in inflammation (eg, immunoglobulin production; antigen processing and presentation; and the chemoattraction and activation of granulocytes, T cells, and B cells). Several proinflammatory genes were downregulated. In contrast, some anti-inflammatory genes were upregulated. The gene that increased most in terms of expression was uteroglobin. This was confirmed with real-time PCR. By contrast, expression of uteroglobin was lower in untreated polyps than in healthy nasal mucosa. Immunohistochemical investigation showed staining of uteroglobin in the epithelium and in seromucous glands in control subjects and in nasal polyps. CONCLUSION: Upregulation of anti-inflammatory genes, such as uteroglobin, might contribute to the effects of local treatment with GCs in nasal polyps. 相似文献