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61.
Mesenteric lymph nodes are critical for the induction of high-dose oral tolerance in the absence of Peyer's patches 总被引:7,自引:0,他引:7
Spahn TW Weiner HL Rennert PD Lügering N Fontana A Domschke W Kucharzik T 《European journal of immunology》2002,32(4):1109-1113
We have previously demonstrated the loss of oral tolerance (OT) in lymphotoxinalpha-/- (LTalpha-/-) and TNFalpha / lymphotoxinalpha deficient (TNFalpha / LTalpha-/-) mice which have defective Peyer's patches (PP) and lymph node (LN) development. We have now studied OT in BALB / c mice with differential defects of the gut-associated lymphoid tissue (GALT) caused by inhibition of LTbetaR signaling during fetal development. Treatment of pregnant mice with LTbetaR-IgG (LTbetaRIgG) and TNFR I55-IgG (TNFR55IgG) abrogates the formation of PP (LTbetaRIgG) or of PP and mesenteric LN (MLN) (LTbetaRIgG / TNFRIgG) without genetically deleting the respective cytokine pathways. OT was readily induced in mice without PP but retaining MLN (PP null / LN +). In contrast, OTcould not be induced in mice lacking both MLN and PP (PP null / MLN null) as shown by the inability of these mice to suppress IFN-gamma secretion or DTH reactions. We next assessed OT in 129 x B6 LTalpha-/- mice with and without MLN. Timed treatment of pregnant LTalpha-/- mice with an agonist anti-LTbetaR mAb induces formation of MLN but not of PP in LTalpha-/- mice. LN + LTalpha-/- mice developed OT while LN LTalpha-/- mice were resistant to OT induction. Taken collectively, the data show that in the presence of MLN PP are not required for OT induction and that the presence of MLN is sufficient for OT induction in the LTalpha-/- model. 相似文献
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64.
Introduction: bispecific antibodies 总被引:3,自引:0,他引:3
65.
Amy C Brodkey Frederick S Sierles Ilyse L Spertus Cindy L Weiner Fredrick A McCurdy 《Academic medicine》2002,77(11):1112-1120
PURPOSE: Little is known about the effect of managed care on medical students' education. Because clerkship directors (CDs) are especially well positioned to observe any changes, this study surveyed CDs from six medical specialties about their perceptions of the effects of managed care on medical students' education. METHOD: Anonymous questionnaires were mailed to 808 CDs from departments of six medical specialties at 125 U.S. allopathic medical schools between October 1997 and March 1998. Among other questions, respondents were asked whether they had observed changes in 19 different aspects of medical students' education, whether these changes were beneficial or detrimental, and whether they believed the changes were due to managed care and/or to other factors. Results were analyzed to determine perceptions of the overall magnitude and source(s) of changes, the perceived positive versus negative effect of managed care, and whether these outcomes were statistically associated with the perceived degree of managed care's market penetration. RESULTS: Five hundred questionnaires (61.9%) were returned. For full-time and voluntary faculty teaching, faculty availability for educational administration, directors' clinical responsibilities, and quality of professional life, the most common response was that managed care had an adverse effect. For faculty's enthusiasm for teaching, directors' administrative and educational duties, and clerkship training sites, the second most common response after "not changed" was that managed care had a negative effect. The majority of respondents held negative opinions of managed care and thought that medical students did not understand it. CONCLUSIONS: CDs in six medical specialties perceived that managed care has negatively affected medical students' education. These perceptions may influence medical students' education. Measures must be taken to ensure excellent education through adequate resources and training in the context of high-quality medical care. 相似文献
66.
Annika?E?StenbergEmail author Lisskulla?Sylvén Carl?GM?Magnusson Malou?Hultcrantz 《Journal of negative results in biomedicine》2004,3(1):6
Disturbances in the immune system has been described in Turner syndrome, with an association to low levels of IgG and IgM
and decreased levels of T- and B-lymphocytes. Also different autoimmune diseases have been connected to Turner syndrome (45,
X), thyroiditis being the most common. 相似文献
67.
Cherri Hobgood Armando Hevia Joshua H Tamayo-Sarver Bryan Weiner Ralph Riviello 《Academic medicine》2005,80(8):758-764
PURPOSE: To determine emergency medicine residents' emotional and behavioral responses to their medical errors and examine associations between residents' responses to medical error and perceptions of their training. METHOD: In 2003, 55 residents at two U.S. residency programs were asked to complete questionnaires about their errors and responses to their errors in three domains: emotional response, learning behavior, and disclosure. The questions were a mixture of free text, yes/no responses, and some were rated using a five-point Likert scale. Based on a conceptual framework, the authors constructed scales to describe the various domains and associations between the residents' responses to medical error and perceptions of their training were examined using Somers' D. RESULTS: A total of 43 residents returned questionnaires (80%); 40 of these residents described errors. Thirty-three (83%) residents discussed the error with someone; 27 (71%) with the attending and 10 (28%) with the patient/family. Negative emotions were common: 27 (68%) felt remorse, 21 (53%) guilt, 23 (58%) inadequacy, and 22 (55%) frustration. Residents' negative emotional responses were associated with their personal characteristics [26% (95% CI, 5-47%) association with lack of experience] and residents' perceptions of their training environment: 15% association with job overload (95% CI, -8-38%) and 23% association with lack of institutional support (95% CI, 5-41%). While 32 (81%) residents increased attention to detail, only 2 (5%) increased their use of evidence-based medicine. CONCLUSIONS: Errors committed by emergency medicine residents often resulted in negative emotions, limited constructive system-based improvements, and inadequate disclosure. Negative perceptions of the training environment are associated with negative emotional responses. 相似文献
68.
A point mutation in the 5' splice site of the dystrophin gene first intron responsible for X-linked dilated cardiomyopathy 总被引:3,自引:4,他引:3
Milasin J; Muntoni F; Severini GM; Bartoloni L; Vatta M; Krajinovic M; Mateddu A; Angelini C; Camerini F; Falaschi A; Mestroni L; Giacca M 《Human molecular genetics》1996,5(1):73-79
X-linked dilated cardiomyopathy (XLDC) is a familial heart disease
presenting in young males as a rapidly progressive congestive heart
failure, without clinical signs of skeletal myopathy. This condition has
recently been linked to the dystrophin gene in some families and deletions
encompassing the genomic region coding for the first muscle exon have been
detected. In order to identify the defect responsible for this disease at
the molecular level and to understand the reasons for the selective heart
involvement, a family with a severe form of XLDC was studied. In the
affected members, no deletions of the dystrophin gene were observed.
Analysis of the muscle promoter, first exon and intron regions revealed the
presence of a single point mutation at the first exon-intron boundary,
inactivating the universally conserved 5' splice site consensus sequence of
the first intron. This mutation introduced a new restriction site for MseI,
which cosegregates with the disease in the analyzed family. Expression of
the major dystrophin mRNA isoforms (from the muscle-, brain- and Purkinje
cell-promoters) was completely abolished in the myocardium, while the
brain- and Purkinje cell- (but not the muscle-) isoforms were detectable in
the skeletal muscle. Immunocytochemical studies with anti- dystrophin
antibodies showed that the protein was reduced in quantity but normally
distributed in the skeletal muscle, while it was undetectable in the
cardiac muscle. These findings indicate that expression of the muscle
dystrophin isoform is critical for myocardial function and suggest that
selective heart involvement in dystrophin- linked dilated cardiomyopathy is
related to the absence, in the heart, of a compensatory expression of
dystrophin from alternative promoters.
相似文献
69.
70.
Two cases of malacoplakia involving Bartholin's glands occurred in postmenopausal women. Grossly the lesions were ovoid cysts with rubbery, soft walls. Microscopically there were sheets of von Hansemann's histiocytes and rare Michaelis-Gutmann bodies. After surgical excision, both patients remained asymptomatic. These cases involving Bartholin's glands are, to our knowledge, the first reported in the female genital tract. 相似文献