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101.
Ertekin-Taner N Allen M Fadale D Scanlin L Younkin L Petersen RC Graff-Radford N Younkin SG 《Human mutation》2004,23(4):334-342
Risk for late onset Alzheimer disease (LOAD) and plasma amyloid beta levels (Abeta42; encoded by APP), an intermediate phenotype for LOAD, show linkage to chromosome 10q. Several strong candidate genes (VR22, PLAU, IDE) lie within the 1-lod support interval for linkage. Others have independently identified haplotypes in the chromosome 10q region harboring IDE that show highly significant association with intermediate AD phenotypes and with risk for AD. To pursue these associations, we analyzed the same haplotypes for association with plasma Abeta42 in 24 extended LOAD families and for association with LOAD in two independent case-control series. One series (MCR, 188 age-matched case-control pairs) did not show association (p=0.64) with the six haplotypes in the 276-kb region spanning three genes (IDE, KNSL1, and HHEX) previously shown to associate with LOAD. The other series (MCJ, 109 age-matched case-control pairs) showed significant (p=0.003) association with these haplotypes. In the MCJ series, the H4 (odds ratio [OR]=5.1, p=0.003) and H2(H7) haplotypes (OR=0.60, p=0.04) had the same effects previously reported. In this series, the H8 haplotype (OR=2.7, p=0.098) also had an effect similar as in one previous case control series but not in others. In the extended families, the H8 haplotype was associated with significantly elevated plasma Abeta42 (p=0.02). In addition, the H5(H10) haplotype, which is associated with reduced risk for AD in the other study is associated with reduced plasma Abeta42 (p=0.007) in our family series. These results provide strong evidence for pathogenic variant(s) in the 276-kb region harboring IDE that influence intermediate AD phenotypes and risk for AD. 相似文献
102.
An automated method was used to record the temporal pattern of feeding of lines of mice selected over 15 generations for high and low body weight (L-mice and S-mice, respectively). Both L-mice and S-mice eat in meals concentrated during the night, and meal frequency is similar in the two lines, but L-mice consume much larger meals, each made up of many more separate feeding bouts. The outbred strain from which the selected lines were derived has a similar basic pattern of feeding in meals, which becomes like that of L-mice when the animal's thermogenic metabolic rate is high, and like that of S-mice when it is low, suggesting that the differences between the feeding patterns of the two selected lines are a secondary consequence of alterations in whole body metabolic rate. 相似文献
103.
R S Janssen M E St Louis G A Satten S E Critchley L R Petersen R S Stafford J W Ward D L Hanson N Olivo C A Schable 《The New England journal of medicine》1992,327(7):445-452
BACKGROUND. Routine, voluntary testing of hospital patients for the human immunodeficiency virus (HIV) has been proposed in order to identify those with early HIV infection in a setting where there is ready access to counseling, appropriate clinical referral, evaluation, and therapy. We studied the pattern of HIV infection among patients in 20 U.S. hospitals, in order to evaluate possible national strategies for the routine, voluntary HIV counseling and testing of hospital patients. METHODS. Blood specimens remaining after clinical use from a systematically selected sample of patients at 20 hospitals in 15 U.S. cities were tested anonymously for antibody to HIV type 1 (HIV-1). Multivariate regression was used to determine which variables best predicted HIV seroprevalence in individual hospitals. Using these data, we estimated the number of HIV-positive patients in all U.S. hospitals and considered the efficiency of routine counseling and testing in different subgroups of patients and hospitals. RESULTS. From September 1989 through October 1991, 9286 of 195,829 specimens (4.7 percent) were positive for HIV-1 in the 20 hospitals. The seroprevalence of HIV at these institutions ranged from 0.2 percent to 14.2 percent. Among HIV-positive patients, 32 percent had symptomatic HIV infection or the acquired immunodeficiency syndrome (AIDS) at the time of admission or evaluation. In the 20 hospitals, HIV seroprevalence was 10.4 times (95 percent confidence interval, 8.8 to 12.0) the AIDS-diagnosis rate (the annual number of patients with new diagnoses of AIDS per 1000 discharges in 1990). In a multivariate model that included 13 hospital-specific variables, only the AIDS-diagnosis rate was associated with the hospital-specific HIV-seroprevalence rate (P less than 0.001). Using these data and the AIDS-diagnosis rates for all U.S. acute care hospitals, we estimated that 225,000 HIV-positive persons were hospitalized (95 percent confidence interval, 190,000 to 260,000) in all 5558 such hospitals in 1990, including 163,000 persons presenting with conditions other than HIV or AIDS (95 percent confidence interval, 130,000 to 196,000). In 1990, in 593 U.S. hospitals with AIDS-diagnosis rates of 1.0 or more per 1000 discharges, HIV testing of patients 15 to 54 years old (3 million patients, or 12.0 percent of all patients in U.S. acute care hospitals) would have identified an estimated 68 percent of all HIV-positive patients (110,000 patients) who were admitted with conditions other than symptomatic HIV infection or AIDS. CONCLUSIONS. We estimate that about 225,000 HIV-positive persons were hospitalized in 1990, of whom only one third were admitted for symptomatic HIV infection or AIDS. Routine, voluntary HIV testing of patients 15 to 54 years old in hospitals with 1 or more patients with newly diagnosed AIDS per 1000 discharges per year could potentially have identified as many as 110,000 patients with HIV infection that was previously unrecognized. 相似文献
104.
105.
Schewe C Goldmann T Grosser M Zink A Schlüns K Pahl S Ulrichs T Kaufmann SH Nerlich A Baretton GB Dietel M Vollmer E Petersen I 《Virchows Archiv : an international journal of pathology》2005,447(3):573-585
The present study is based on the initiative for quality assurance in pathology of the German Society of Pathology and the Professional Association of German Pathologists. Four panel laboratories with experience and expertise in polymerase chain reaction (PCR) detection of Mycobacterium tuberculosis were selected to establish the prerequisites for continuous external laboratory trials, in particular, by providing pre-tested specimens and evaluation criteria for participating institutes. In the first step, the four panel laboratories performed an internal trial to test their own reliability and reproducibility. Paraffin sections and DNA preparations from 34 tissues (25 clinical specimens and 9 controls) totalling to 66 samples were evaluated by each panel institute according to their own protocols. The methodologies differed and are described in detail. Despite these differences, a high degree of inter-laboratory reliability was achieved. In this report, we summarise our results including the correlation with the histology and provide recommendations for applying PCR-based methodology for the detection of mycobacterial DNA in surgical specimens. Supplementary data are available online at (rubric Forschung). Pre-tested specimens are now available for the external trial and can be ordered from the steering institute via Oligene (). All molecular pathology laboratories are invited to participate in this quality assurance initiative. 相似文献
106.
The purpose of this study was to assess the time of onset of action of acrivastine in suppressing the wheal response to histamine (10 mg/ml) and allergen (10000 and 100000 BU/ml) in the skin prick test. Ten subjects with a well-documented allergy to pollen received single doses of 8 mg of acrivastine and placebo according to a randomized, double-blind, placebo-controlled, crossover treatment design. Duplicate skin prick tests were performed 0, 15, 20, 25, 30, and 60 min after medication. The results demonstrated a statistically significant suppression of the wheal reactions 15–20 min after medication, depending on the reaction producers used. The sum of all three producers showed a statistically significant effect on the wheal reaction 15 min after medication. The upper 95% confidence limit for time lag from dosing of acrivastine until reduction from placebo level commences was 6.5 min. The study substantiates that orally administered acrivastine has a rapid onset of action in the skin of allergic subjects. The results indicate that allergen SPT is a more sensitive tool for studying antihistaminergic activity than histamine SPT. 相似文献
107.
Quantitative gene expression analysis reveals transition of fetal liver progenitor cells to mature hepatocytes after transplantation in uPA/RAG-2 mice 总被引:14,自引:0,他引:14
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108.
Barfoed AM Petersen TR Kirkin AF Thor Straten P Claesson MH Zeuthen J 《Scandinavian journal of immunology》2000,51(2):128-133
Mutations in the tumour suppressor gene p53 are among the most frequent genetic alterations in human malignancies, often associated with an accumulation of the p53 protein in the cytoplasm. We have generated a number of cytotoxic T lymphocyte (CTL) clones that specifically recognize the HLA-A*0201 p53 wild type peptide RMPEAAPPV [65-73], designated R9V, by the in vitro stimulation of CD8 enriched peripheral blood lymphocytes from a healthy HLA-A*0201 donor using peptide loaded autologous dendritic cells. A total of 22 CTL clones were generated from the same bulk culture and demonstrated to carry identical T-cell receptors. The CTL clone, 2D9, was shown to specifically lyse the HLA-A*0201+ squamous carcinoma cell line SCC9 and the breast cancer cell line MDA-MB-468. Our data demonstrate that human peripheral blood lymphocytes from normal healthy individuals comprise T cells capable of recognizing p53 derived wild type (self) peptides. Furthermore, the capacity of R9V specific T cell clones to exert HLA restricted cytotoxicity, argues that the R9V peptide is naturally presented on certain cancer cells. This supports the view that p53 derived wild type peptides might serve as candidate target antigens for the immunotherapeutic treatment of cancer. 相似文献
109.
Chagas' disease, the leading cause of heart failure in Latin America, results from infection with the intracellular protozoan parasite Trypanosoma cruzi. Host cell responses elicited in the myocardium early in the infective process are thought to be critical for establishment of infection by this pathogen; however, these changes have not been well characterized. We report here that primary cardiomyocytes undergo hypertrophy as an early response to T. cruzi infection. The T. cruzi-elicited hypertrophic response is characterized by increased expression of genes encoding the contractile proteins MyHC beta and MyHC alpha, followed by an approximately twofold increase in cell size. Hypertrophy was observed in both parasite-containing and noninfected cell populations represented in T. cruzi-infected cultures, indicating the involvement of a soluble mediator in this process. Conditioned medium harvested from T. cruzi-infected cultures, which contained significant levels of interleukin-1 beta (IL-1 beta) but not endothelin-1 or tumor necrosis factor alpha, was sufficient to induce hypertrophy in isolated cardiomyocytes. Addition of a high-affinity receptor chimera, IL-1 trap, to cardiomyocyte cultures blocked the overall increase in cell size elicited by T. cruzi. These novel findings indicate that IL-1 beta, which is rapidly induced in response to T. cruzi, promotes cardiomyocyte hypertrophy early in the infective process and may contribute to maintenance of cardiomyocyte function during establishment of T. cruzi infection in the heart. 相似文献
110.
Carol A. E. Nickerson Gary H. McClelland Doreen M. Petersen 《Journal of behavioral medicine》1991,14(3):241-266
Previous assessments of individuals' values for various contraceptive consequences have employed one of four methodologies: free elicitation, direct ratings, multiple regression, or factor analysis. All four methodologies are flawed because they produce group rather than individual values, rely on rating scales, and fail to incorporate information regarding consequence trade-offs. Axiomatic conjoint measurement is proposed as an alternative methodology and used to determine individuals' values for a selected set of contraceptive consequences at two stages of the family-planning career.Preparation of this paper was supported in part by Grants HD-10802 and HD-14403 from the National Institute of Child Health and Human Development. Appreciation is due the Statistical Computing Facility of the University of California at Berkeley. Requests for reprints should be sent to the Publications Librarian, Center for Research on Judgment and Policy, Muenzinger Psychology Building, University of Colorado, Boulder, Colorado 80309-0344. 相似文献