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Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
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R Blok D H Margulies L Pease R K Ribaudo J Schneck J McCluskey 《International immunology》1992,4(4):455-466
The influence of CD8 on the fine specificity of MHC class I-restricted T cell allorecognition was evaluated by comparing the reactivity of CD8- and CD8-transfected forms of an allospecific, H-2Kb-restricted T hybridoma. The CD8- T hybridoma responded to cells expressing H-2Kb, H-2Kbm6, and the individual H-2Kb----bm10 back mutations 165V----M, 173K----E, and 174N----L. Under the same conditions the CD8- T hybridoma responded poorly or not at all to cells expressing H-2Kbm10, H-2Kbm8, the individual H-2Kb----bm10 back mutants 163T----A and 167W----S, and the individual H-2Kb----bm8 back mutations 22Y----F and 24E----S. In contrast, T hybridoma cells expressing high levels of CD8 reacted strongly with antigen presenting cells (APC) expressing H-2Kb and H-2Kbm6 molecules, as well as APC expressing H-2Kbm10 (weakly), H-2Kbm8, and all five individual H-2Kb----bm10 and the two H-2Kb----bm8 back mutants 22Y----F and 24E----S. The mutations which distinguish the T cell recognition of both H-2Kbm10 and H-2Kbm8 from H-2Kb are predicted to control the interaction of these class I molecules with antigenic peptides in the binding site, implying an important role for peptide antigen in T cell allorecognition. Nonetheless, CD8 expression by the H-2Kb-restricted T cells conferred novel or enhanced alloreactivity with cells expressing H-2Kbm10, H-2Kbm8, and each of the individual H-2Kb----bm10 and H-2Kb----bm8 back mutants. These findings reflect an important role for CD8 in influencing the fine specificity of MHC class I recognition by T cells and may indicate a limited structural role for peptide antigen in defining the ligand recognized by these alloreactive T cells. 相似文献
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols. 相似文献
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Urogenital Chlamydia trachomatis serovars in men and women with a symptomatic or asymptomatic infection: an association with clinical manifestations? 总被引:10,自引:0,他引:10
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Morré SA Rozendaal L van Valkengoed IG Boeke AJ van Voorst Vader PC Schirm J de Blok S van Den Hoek JA van Doornum GJ Meijer CJ van Den Brule AJ 《Journal of clinical microbiology》2000,38(6):2292-2296
To determine whether certain Chlamydia trachomatis serovars are preferentially associated with a symptomatic or an asymptomatic course of infection, C. trachomatis serovar distributions were analyzed in symptomatically and asymptomatically infected persons. Furthermore, a possible association between C. trachomatis serovars and specific clinical symptoms was investigated. C. trachomatis-positive urine specimens from 219 asymptomatically infected men and women were obtained from population-based screening programs in Amsterdam. Two hundred twenty-one C. trachomatis-positive cervical and urethral swabs from symptomatically and asymptomatically infected men and women were obtained from several hospital-based departments. Serovars were determined using PCR-based genotyping, i.e., restriction fragment length polymorphism analysis of the nested-PCR-amplified omp1 gene. The most prevalent C. trachomatis serovars, D, E, and F, showed no association with either a symptomatic or asymptomatic course of infection. The most prominent differences found were (i) the association of serovar Ga with symptoms in men (P = 0.0027), specifically, dysuria (P < 0.0001), and (ii) detection of serovar Ia more often in asymptomatically infected people (men and women) (P = 0.035). Furthermore, in women, serovar K was associated with vaginal discharge (P = 0.002) and serovar variants were found only in women (P = 0.045). 相似文献
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Mahadevaiah SK; Odorisio T; Elliott DJ; Rattigan A; Szot M; Laval SH; Washburn LL; McCarrey JR; Cattanach BM; Lovell-Badge R; Burgoyne PS 《Human molecular genetics》1998,7(4):715-727
An RNA-binding motif (RBM) gene family has been identified on the human Y
chromosome that maps to the same deletion interval as the 'azoospermia
factor' (AZF). We have identified the homologous gene family (Rbm) on the
mouse Y with a view to investigating the proposal that this gene family
plays a role in spermatogenesis. At least 25 and probably >50 copies of
Rbm are present on the mouse Y chromosome short arm located between Sry and
the centromere. As in the human, a role in spermatogenesis is indicated by
a germ cell-specific pattern of expression in the testis, but there are
distinct differences in the pattern of expression between the two species.
Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are
female due to a position effect resulting in non-expression of Sry ;
sex-reversing such mice with an Sry transgene produces males with a high
incidence of abnormal sperm, making this the third deletion interval on the
mouse Y that affects some aspect of spermatogenesis. Most of the copies of
Rbm map to this deletion interval, and the Yd1males have markedly reduced
Rbm expression, suggesting that RBM deficiency may be responsible for, or
contribute to, the abnormal sperm development. In man, deletion of the
functional copies of RBM is associated with meiotic arrest rather than
sperm anomalies; however, the different effects of deletion are consistent
with the differences in expression between the two species.
相似文献