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291.
Suvi M. Virtanen Merja Roivainen Maria A. Andersson Petri Ylipaasto Douwe Hoornstra Raimo Mikkola Mirja S. Salkinoja-Salonen 《Toxicon》2008,51(6):1029-1037
Cereulide is a K+ ionophore cytotoxic and mitochondriotoxic to primary cells and cell lines of human and other mammalian origins. It is a heat-stable, highly lipophilic (log Kow 5.96) peptide (1152 g mol−1) produced by certain strains of Bacillus cereus, a bacterium connected to emetic food poisonings. In this study the pancreatic toxicity of purified cereulide, and cereulide-containing bacterial extracts, was studied using fetal porcine Langerhans islets in culture. Exposure to 1 ng ml−1 of purified cereulide caused necrotic cell death of the islet cells impairing their insulin content within 2 days. Cell extracts of cereulide-positive B. cereus strains connected to food poisoning or isolated from foodstuffs were toxic, corresponding to their measured cereulide content. Extracts of B. cereus strains producing or not producing the B. cereus diarrheal toxin, but no cereulide, were tolerated by the porcine islet cultures up to concentrations 1000-fold higher compared to extracts from strains containing cereulide, and up to exposure times of 7 d. Cereulide thus was identified as the B. cereus-produced substance toxic towards porcine fetal Langerhans islets and beta cells. 相似文献
292.
Comparison of Performances of Two Commercially Available Tests, a PCR Assay and a Ligase Chain Reaction Test, in Detection of Urogenital Chlamydia trachomatis Infection 总被引:12,自引:0,他引:12
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Mirja Puolakkainen Eija Hiltunen-Back Timo Reunala Satu Suhonen Pekka Lhteenmki Matti Lehtinen Jorma Paavonen 《Journal of clinical microbiology》1998,36(6):1489-1493
The diagnostic performance of a PCR test (Roche Cobas Amplicor CT/NG Test) and that of a ligase chain reaction (LCR) test (Abbott LCx Chlamydia trachomatis assay) were compared by using endocervical and urethral swab specimen culture as a reference test. First-void urine (FVU) and endocervical and urethral swab specimens were collected from 1,015 unselected patients attending a sexually transmitted disease clinic and a clinic for adolescents in Helsinki, Finland. Chlamydia trachomatis was cultured from samples from the endocervix or urethra. PCR was performed with fresh and frozen urine and the culture transport medium. LCR was performed with fresh and frozen urine and LCx swab transport medium. Diagnostic consistency and diagnostic accuracy were statistically tested. The test results were identical for 984 patients (97%). Discrepant results were observed for 31 patients. Overall, LCR and PCR showed excellent kappa coefficients of consistency for both swab and FVU specimens (0.93 and 0.95, respectively). Sixty-one patients (6%) were culture positive. Testing of FVU by LCR or PCR increased the overall positivity rates to 7.0 and 7.7%, respectively. While PCR of FVU detected the greatest number of C. trachomatis infections (sensitivity, 96.1%), for some PCR-positive FVU specimens the results could not be confirmed (specificity, 99.6%). PCR and LCR were more sensitive than culture (sensitivities, 92 and 93% versus 79% for culture) in the diagnosis of genital C. trachomatis infection. In conclusion, both tests can be recommended for use in the clinical laboratory and for the screening of asymptomatic C. trachomatis infections. 相似文献
293.
Ilkka Julkunen Pentti Ukkonen Mirja Stenvik Tapani Hovi Laura Renkonen Olli Mäkelä 《Journal of clinical immunology》1987,7(4):319-326
Immunoglobulin isotype composition of poliovirus antibodies was studied by isotype-specific solid-phase radio-immunoassay (RIA) in four patients with paralytic poliomyelitis, five adults receiving live poliovirus vaccine as a booster immunization, and seven children receiving first doses of inactivated poliovirus vaccine. In paralytic poliomyelitis serum and cerebrospinal flind (CSF) poliovirus antibodies were mainly of IgG1, IgG3, and IgA isotypes. IgM antibodies were found in sera but not in CSF. Either IgG2 and IgG4 antibodies were undetectable or the titers were low. In adults who had received live trivalent poliovirus vaccine, antibodies against poliovirus type 3 were detected in IgG1 (53% of total antibodies), IgG3 (25%), IgM (9%), IgA (8%), IgG2 (3%), and IgG4 (2%) isotypes. In prevaccination and late postvaccination sera the share of IgG3 antibodies was exceptionally high (35%). In children who received inactivated poliovirus vaccine, antibodies developed in IgG1 (53–61% of total antibodies for poliovirus types 1, 2, and 3), IgG3 (12–21%), and IgM (23–33%) isotypes. Antibody levels in IgG2, IgG4, and IgA isotypes were low and observed only in a few cases. Like other viral antibodies IgG1 and IgG3 isotypes were the major IgG subclasses in poliovirus antibodies. 相似文献
294.
Sarén A Pascolo S Stevanovic S Dumrese T Puolakkainen M Sarvas M Rammensee HG Vuola JM 《Infection and immunity》2002,70(7):3336-3343
Chlamydia pneumoniae is a common intracellular human pathogen that has been associated with several severe pathological conditions, including coronary heart disease and atherosclerosis. There is no vaccine against C. pneumoniae infection, but CD8(+) T cells have been shown to be crucial for protection during experimental infection. However, the effector functions and epitope specificity of the protective CD8(+) T cell remain unknown. The aim of this study was to identify C. pneumoniae-derived mouse CD8 epitopes by using a recent epitope prediction method. Of four C. pneumoniae proteins (the major outer membrane protein, outer membrane protein 2, polymorphic outer membrane protein 5, and heat shock protein 60), 53 potential CD8(+) T-cell epitopes were predicted by H-2 class I binding algorithms. Nineteen of the 53 peptides were identified as CD8 epitopes by testing for induction of a cytotoxic response after immunization. To test whether the predicted epitopes are naturally processed and presented by C. pneumoniae-infected cells, we generated a panel of seven peptide-specific cytotoxic T lymphocyte lines that were subsequently tested for recognition of C. pneumoniae-infected target cells. By using this strategy, we were able to identify three C. pneumoniae CD8 epitopes that were, indeed, processed and presented on infected cells. Identification of these natural CD8 epitopes provides tools for characterization of CD8(+) T-cell function in vivo and generation of epitope-specific prevention strategies. 相似文献
295.
Jaana T. Kari Jutta Viinikainen Petri Böckerman Tuija H. Tammelin Niina Pitkänen Terho Lehtimäki Katja Pahkala Mirja Hirvensalo Olli T. Raitakari Jaakko Pehkonen 《Scandinavian journal of medicine & science in sports》2020,30(7):1194-1204
Physical inactivity is a major health risk worldwide. Observational studies suggest that higher education is positively related to physical activity, but it is not clear whether this relationship constitutes a causal effect. Using participants (N = 1651) drawn from the Cardiovascular Risk in Young Finns Study linked to nationwide administrative data from Statistics Finland, this study examined whether educational attainment, measured by years of education, is related to adulthood physical activity in terms of overall physical activity, weekly hours of intensive activity, total steps per day, and aerobic steps per day. We employed ordinary least squares (OLS) models and extended the analysis using an instrumental variables approach (Mendelian randomization, MR) with a genetic risk score as an instrument for years of education. Based on the MR results, it was found that years of education is positively related to physical activity. On average, one additional year of education leads to a 0.62-unit higher overall physical activity (P < .01), 0.26 more hours of weekly intensive activity (P < .05), 560 more steps per day (P < .10), and 390 more aerobic steps per day (P < .09). The findings indicate that education may be a factor leading to higher leisure-time physical activity and thus promoting global health. 相似文献
296.
297.
Chesebro BB Blessing E Kuo CC Rosenfeld ME Puolakkainen M Campbell LA 《Cardiovascular research》2003,60(1):170-174
OBJECTIVE: Chlamydia pneumoniae infection has been associated with atherosclerosis, although the mechanisms by which C. pneumoniae contribute to atherogenesis remain unclear. Altered production of nitric oxide, a known bactericidal and anti-inflammatory agent, represents one possible mechanistic link. To examine this issue, a diet-induced, hyperlipidemic mouse model of early atherosclerosis was used. METHODS: A series of intranasal inoculations of C. pneumoniae strain AR-39 were administered to mice lacking endothelial or inducible nitric oxide synthase and to normal controls. After 18 weeks on an atherogenic diet, atherosclerotic lesion area in the aortic sinus was measured using computer-assisted morphometry. RESULTS: In the absence of C. pneumoniae infection, diet-fed eNOS(-/-) mice developed enlarged fatty streak lesions of borderline significance in comparison to uninfected, wild-type mice, while the lesion area in uninfected, diet-fed iNOS(-/-) mice did not differ significantly from lesion area in wild-type animals. In contrast, lesion area in infected eNOS(-/-) mice increased slightly, but not significantly in comparison to uninfected eNOS(-/-) mice. Lesion area in the infected iNOS(-/-) mice was significantly enlarged when compared to both uninfected iNOS(-/-) mice as well as to infected wild-type mice. CONCLUSIONS: These data suggest that production of nitric oxide by eNOS protects against development of fatty streak lesions in uninfected hyperlipidemic mice, but does not offer additional protection in infected hyperlipidemic mice, while iNOS may play a protective role, thus limiting chlamydial exacerbation of fatty streak lesions. 相似文献
298.
299.
Wu GH Auvinen A Yen AM Hakama M Tammela TL Stenman UH Kujala P Ruutu M Chen HH 《European urology》2012,61(5):1011-1018