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111.
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   
112.
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   
113.
H. Ipsen    B. Schwartz    J.-Å. Wihl    B. Nüchel  Petersen  E. P. Munch    H. Janniche  H. Løwenstein 《Allergy》1988,43(5):370-377
Patients allergic to pollen from alder, birch and hazel were hyposensitized during a 3-year period with either birch pollen extract alone (n = 24) or a mixture of one or more of alder, birch and hazel pollen extracts (n = 27). The effect of the treatment was evaluated by RAST and tandem crossed-radioimmunoelectrophoresis (tandem-CRIE). The patient' specific IgE response to the major allergens of alder (Aln g I), birch (Bet v I) and hazel (Cor a I and Cor a II), as measured by tandem-CRIE, and the total specific IgE response, measured by RAST, decreased significantly (Pc less than 0.05) during immunotherapy, irrespective of the extract used during the treatment. There was no significant difference (Pc less than 0.05) between the two treatment groups. The results obtained indicate either that birch pollen extract alone is adequate in the treatment of the studied patient group or the patients had been sensitized towards birch pollen alone.  相似文献   
114.
The in vivo administration of monoclonal antibody (mAb) to the CD4 antigen associated with helper T cells has been successful in prolonging the survival of nonhuman primates with experimental allergic encephalomyelitis (EAE). EAE was induced in 17 outbred longtailed macaques (Macaca fascicularis) by inoculation of homologous myelin basic protein (BP) in complete Freund's adjuvant (CFA). Treatment was begun at the onset of clinical signs. Eleven animals were treated with anti-CD4 mAb Leu3a (eight) or OKT4a (three). Of the six control animals, two received anti-CD8 mAb (Leu2a), and four were treated with saline. Specific T- and B-cell subsets which have been implicated in the development of EAE were monitored throughout the course of the disease by one- and two-color immunofluorescence (IF). The monkey anti-BP antibody and anti-mouse immunoglobulin (IgG) responses were measured by enzyme-linked immunoassay (ELISA) techniques, as were the levels of free-circulating murine IgG. The nature of the infiltrating lymphocytes in the brain was evaluated histologically post mortem. Our results indicate that anti-CD4 mAb can prolong survival and in some cases completely reverse the clinical appearance of the disease; however, relapses did occur. Treatments with Leu3a or OKT4a anti-CD4 mAbs reversed the ongoing depletion of CD4+ and CD8+ cells caused by the development of EAE and appeared to reduce the size and degree of inflammation in brain lesions. These treatments did not induce immunologic tolerance to mouse IgG since all of the anti-CD4-treated animals produced high titers of anti-mouse IgG antibodies. Treatment with Leu2a (anti-CD8) had no effect on the development of EAE. These results suggest that CD4+ cells are important to the pathogenesis of EAE in macaques and that manipulation of this subset with monoclonal antibodies may provide effective treatment of human demyelinating disease.  相似文献   
115.
An enzyme-linked immunosorbent assay (ELISA) for detection of immunoglobulin M (IgM) antibodies against the periplasmatic flagellum of the Reiter treponeme is described. IgM in the test samples was bound to anti-IgM-coated microtest plates, and flagellum-specific IgM antibody was subsequently detected by incubation with a purified flagellum preparation and monospecific anti-flagellum conjugate. Rheumatoid factor, antinuclear antibodies, or flagellum-specific IgG did not interfere. The specificity of the ELISA for IgM antibodies was 99.5% for sera from 200 blood donors and 98.6% for 147 patient sera that gave false-positive reactions in other syphilis serological tests. The sensitivity was 88.5% for sera from 87 patients with first-time primary syphilis, 93.5% for sera from 62 patients with first-time secondary syphilis, 21.4% for sera from 42 patients who were reinfected, and 0% for sera from 13 patients with late syphilis. Of the sera from 153 patients with treated syphilis, 7.2% had IgM antibodies, and sera from patients with primary or secondary syphilis generally had no IgM antibodies 6 months after treatment. The finding of IgM antibodies indicates that patients should receive antisyphilis treatment if they have not been treated recently, but a negative result does not exclude the possibility of active syphilis. The method may prove useful for the diagnosis of congenital syphilis in newborns.  相似文献   
116.
BACKGROUND: It has been suggested that finger length may correlate with function or disorders of the male reproductive system. This is based on the HOXA and HOXD genes' common embryological control of finger development and differentiation of the genital bud. The objective of this study was to explore the association between the ratio of 2nd to 4th finger length (2D:4D ratio) and testis function in a sample of young Danish men from the general population. METHODS: Semen samples and finger measurements were obtained from a total of 360 young Danish men in addition to blood samples for sex hormone analysis to describe the possible association between 2D:4D and semen and sex-hormone parameters. RESULTS: A statistically significant inverse association with the 2D:4D was found only in relation to hormone levels of FSH in the group of young men with a 2D:4D >1 (P = 0.036) and a direct association with the total sperm count in the group of young men with a 2D:4D < or = 1 (P = 0.045). CONCLUSION: The statistically significant results may be 'false positives' (type I error) rather than representing true associations. This relatively large study of young, normal Danish men shows no reliable association between 2D:4D finger ratio and testicular function. Measurements of finger lengths do not have the power to predict the testicular function of adult men.  相似文献   
117.
N. Ødum    P. Platz    B. K. Jakobsen    C. Munck  Petersen  N. Jacobsen    J. Møller    L. P. Ryder    L. Lamm  A. Svejgaard 《Tissue antigens》1987,30(5):213-216
Thirteen recipients of HLA-haploidentical, DR compatible bone marrow (BM) and the corresponding BM donors were HLA-DP typed using primed lymphocyte typing (PLT). Severe acute GVHD (greater than or equal to grade 2) developed within 3 months after BM-transplantation in all of eight recipients of DP incompatible BM, but in none of five recipients of DP-compatible BM. This difference was highly significant (p less than 0.001, Fisher's exact test). Moreover, severe acute GVHD was significantly increased in recipients of haploidentical, DR compatible, but DP incompatible BM as compared to severe acute GVHD in 88 recipients of HLA-identical BM (p less than 0.0001). In contrast, there was no difference in acute GVHD between recipients of haploidentical, DR and DP compatible BM and recipients of HLA-identical BM. The data presented here provide strong evidence for the first time that HLA-DP antigens play a role as transplantation antigens.  相似文献   
118.
The purpose of this study was to evaluate the effect of varying the type of pelvic and lower extremity stabilization on isometric trunk extension and flexion muscle strength measurements. Two pelvic stabilization systems, one consisting of fixation of the anterior superior iliac spines and sacrum (pelvic fixation) and the second, a strap across the anterior superior iliac spines and a posterior pad at the sacrum (pelvic strap) were compared. The lower extremities were or were not strapped at the thigh, calf, and feet. Torque values for the pelvic fixation system were not different from the pelvic strap system with lower extremity stabilization. Torque values were less with no lower extremity stabilization with both pelvic stabilization systems for flexion but not for extension muscle contractions. The use of an extensive pelvic stabilization system did not produce greater isometric force output than the use of a simple pelvic strap. The use of lower extremity stabilization did produce greater isometric flexion force output than the use of no lower extremity stabilization. J Ortho Sports Phys Ther 1987;9(3):111-117.  相似文献   
119.
We have reported 7 new cases of Bipolaris infection and 2 of Exserohilum infection, which demonstrate the capability of these 2 genera to cause invasive as well as "allergic" disease. As noted previously, it is likely that all of the cases of "Helminthosporium" and Drechslera infections reported in the literature were caused by Bipolaris or Exserohilum. Infections due to these 2 genera are probably more common than previously recognized. They should be included in the differential diagnosis of central nervous system and disseminated fungal disease, sinusitis, keratitis, peritonitis associated with continuous ambulatory peritoneal dialysis, and allergic bronchopulmonary disease. These various entities have distinct histopathologic characteristics. With disseminated disease in the immunocompromised patient, the most frequent findings are acute inflammation with prominent vascular invasion, thrombosis, and infarction. In contrast, granulomatous inflammation and leukocytoclastic vasculitis are seen in meningoencephalitis caused by these fungi. The histologic features of allergic bronchopulmonary disease and sinusitis are similar. A chronic inflammatory infiltrate of lymphocytes, plasma cells and eosinophils within edematous granulation tissue is found in addition to squamous metaplasia and thickening of the basement membrane. Infections caused by Bipolaris/Exserohilum and Aspergillus show many clinical and pathologic similarities despite the lack of taxonomic relationship between these fungi. Both cause disseminated disease in immunocompromised patients that is characterized by tissue necrosis and vascular invasion. Both cause central nervous system disease, osteomyelitis, and sinusitis and are associated with allergic bronchopulmonary disease. Sinusitis, the most common form of disease caused by Bipolaris and Exserohilum, occurs in otherwise healthy patients with nasal polyposis and allergic rhinitis. Although pathologic evidence of bone invasion may not be found, there frequently is radiographic evidence of invasive disease. Most patients who are treated initially with surgical debridement and amphotericin B have apparently been cured. However, longer follow-up will be necessary in these patients. Amphotericin B appears to be the treatment of choice for invasive infections caused by Bipolaris/Exserohilum species. Ketoconazole and other imidazole derivatives may also be effective in certain of the disease entities caused by these black moulds; however, their role has yet to be defined.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
120.
ZK 91296, a partial agonist at benzodiazepine receptors   总被引:2,自引:0,他引:2  
ZK 91296 (ethyl 5-benzyloxy-4-methoxymethyl--carboline-3-carboxylate) is a potent and selective ligand for benzodiazepine (BZ) receptors. Biochemical investigations indicate that ZK 91296 may be a partial agonist at BZ receptors. Such partial agonism may explain to some extent why ZK 91296 needs higher BZ receptor occupancy than diazepam for the same effect against chemical convulsants and for behavioural effects. The lack of sedatiye effects, and the very potent inhibition of reflex epilepsy, spontaneous epilepsy and DMCM-induced seizures suggest, furthermore, that ZK 91296 may possess pharmacological selectivity for a particular type of BZ receptor interaction, perhaps including topographic as well as receptor subtype differentiation.  相似文献   
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