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91.
OBJECTIVES: The noradrenergic innervation of lymphoid organs controls several immune cell functions and local blood perfusion. Considering that cell and antigen uptake depend on the blood supply to lymphoid organs, the hypothesis was tested that feedback signals from activated immune cells control sympathetic vasomotor activity. METHODS: We determined the blood flow in spleen and mesenteric lymph nodes (mLN) of Wistar Kyoto rats during immune stimulation with endotoxin (LPS; 10 microg/kg) and following disruption of the noradrenergic transmission. RESULTS: Our data indicate that (a) the splenic noradrenaline content, which reflects the density of the sympathetic innervation, is 5 times higher in the spleen than in other peripheral organs and the spleen receives stronger tonic sympathetic input than mLN; (b) immune stimulation with LPS causes a 4-fold increase in the IL-1beta production in the spleen, but only 2-fold in mLN; (c) IL-1beta causes an inhibition of the sympathetic vasoconstrictor tonus in the spleen, but has no significant effect on the noradrenergic vascular tonus in mLN, and (d) in mLN, the local hyperemia induced by LPS is attenuated by the degranulation of vesicular stores of histamine and serotonin, indicating that these monoamines participate in the vasodilator effect of LPS in mLN. CONCLUSIONS: The present experiments, taken together with our previous studies, indicate that the control of blood supply to the spleen and mLN involves different mechanisms. While blood perfusion in the spleen depends on the inhibition of the noradrenergic vasoconstriction by endogenously produced IL-1beta, other vasoactive mediators such as serotonin and histamine play a role in the control of mLN perfusion. 相似文献
92.
93.
Richter B Aschendorff A Lohnstein P Husstedt H Nagursky H Laszig R 《The Journal of laryngology and otology》2002,116(7):507-513
The purpose of this study was to evaluate whether use of a positioner for situating the Clarion 1.29 standard electrode array in close proximity to the modiolus, causes damage to fine intra-cochlear structures, and to provide a comparison with results obtained for insertions of the array performed without a positioner. The study was performed in seven freshly frozen human temporal bones. Electrode location and intra-cochlear trauma was analysed using cross-sectional imaging and histological analysis. Insertion of the Clarion array did not reveal major trauma. The devices inserted with the positioner showed a consistently closer location of the electron array towards the modiolus, however, insertion resulted in significant displacement of both the electrode array and the positioner resulting in severe destruction of the basilar membrane and osseous spiral lamina along the length of the basal and middle turns. The devices inserted with the positioner resulted in major trauma to the basilar membrane and osseous spiral lamina. Therefore, systematic safety studies in larger samples of human temporal bones should be performed and the results carefully evaluated before implantation can be recommended unreservedly. 相似文献
94.
Incidence of HIV infection in stable sexual partnerships: a retrospective cohort study of 1802 couples in Mwanza Region,Tanzania 总被引:3,自引:0,他引:3
Hugonnet S Mosha F Todd J Mugeye K Klokke A Ndeki L Ross D Grosskurth H Hayes R 《Journal of acquired immune deficiency syndromes (1999)》2002,30(1):73-80
OBJECTIVE: To describe the dynamics of HIV transmission in stable sexual partnerships in rural Tanzania. DESIGN: Retrospective cohort study nested within community-randomized trial to investigate the impact of a sexually transmitted disease treatment program. METHODS: A cohort of 1802 couples was followed up for 2 years, with the HIV status of each couple assessed at baseline and follow-up. RESULTS: At baseline, 96.7% of couples were concordant-negative, 0.9% were concordant-positive, 1.2% were discordant with the male partner being HIV-positive, and 1.2% were discordant with the female partner being HIV-positive. Individuals living with an HIV-positive partner were more likely to be HIV-positive at baseline (women: odds ratio [OR] = 75.7, 95% confidence interval [CI]: 33.4-172; men: OR = 62.4, CI: 28.5-137). Seroincidence rates in discordant couples were 10 per 100 person-years (py) and 5 per 100 py for women and men, respectively (rate ratio [RR] = 2.0, CI: 0.28-22.1). In concordant-negative couples, seroincidence rates were 0.17 per 100 py in women and 0.45 per 100 py in men (RR = 0.38, CI: 0.12-1.04). Individuals living in discordant couples were at a greatly increased risk of infection compared with individuals in concordant-negative couples (RR = 57.9, CI: 12.0-244 for women; RR = 11.0, CI: 1.2-47.5 for men). CONCLUSION: Men were more likely than women to introduce HIV infection in concordant-negative partnerships. In discordant couples, incidence in HIV-negative women was twice as high as in men. HIV-negative individuals in discordant partnerships are at high risk of infection, and preventive interventions targeted at such individuals are urgently needed. 相似文献
95.
Kilian R Lindenbach I Löbig U Uhle M Petscheleit A Angermeyer MC 《Social science & medicine (1982)》2003,57(6):1127-1142
Empowerment and disempowerment is studied in terms of the way persons with long and persistent schizophrenia evaluate their psychiatric outpatient treatment. One hundred persons with the diagnosis of schizophrenia (ICD-10 F 20.0) were interviewed about their perceptions and evaluation of the treatment process by means of problem-focused interviews. Transcribed interviews were subjected to qualitative content analysis. Relationships among the categories of the qualitative content analysis were analyzed by means of a homogeneity analysis. The latent dimension extracted by the homogeneity analysis could be interpreted as a quantitative measure of an empowered or a disempowered perception of the treatment process. As a result of the qualitative content analysis it was found that a majority of participants tend to describe their treatment as reduced to drug treatment and that they tend to notice only positive medication effects rather than mixed medication effects or positive effects of conversation and that they feel helpless or indifferent rather than actively involved in the treatment process. The impact of socio-demographic, clinical, and treatment characteristics on the participants' location on a latent dimension called "empowerment" was examined by means of multiple regression analysis. General life satisfaction, negative symptoms and getting depot medication were positively associated with a more disempowered perception of the treatment process whereas positive symptoms, getting antidepressant medication and being treated in an outpatient clinic instead of a private practice were associated with a more empowered perception. 相似文献
96.
Scheinichen D Jankowski M Ruschulte H Jüttner B Kleine HD Meyer zu Vilsendorf A Piepenbrock S Heine J 《Nutrition (Burbank, Los Angeles County, Calif.)》2003,19(5):441-445
OBJECTIVE: The anti-inflammatory properties of parenteral nutrition might be improved by enrichment with omega-3 polyunsaturated fatty acids (PUFAs), which are responsible for the enhanced release of metabolites derived from eicosapentaenoic acid. Under physiologic conditions, lymphocyte populations are regulated by cellular mechanisms such as apoptosis. In contrast to cell death by necrosis, apoptosis does not induce an inflammatory response that might injure the host. METHODS: Apoptosis and necrosis of cultured human blood lymphocytes were investigated in vitro after incubation for 48 and 72 h with three lipid emulsions containing 50% medium-chain triacylglycerols. The lipid emulsions differed in the percentage of long-chain triacylglycerols, which were replaced in part by different amounts of omega-3 PUFA (8%, 20%, or 40%). Rates of apoptosis and necrosis of lymphocyte subpopulations were analyzed with a sensitive annexin V flow cytometric assay. RESULTS: After 48 and 72 h of incubation, time- and dose-dependent increases of apoptosis and necrosis, respectively, were found in all lymphocyte subsets regardless of the percentage of omega-3 PUFAs. CONCLUSIONS: Our results suggested that enrichment with omega-3 PUFAs in the tested lipid emulsions does not alter apoptosis and secondary necrosis of lymphocyte populations. Thus PUFAs may exert their functional effects through other mechanisms. 相似文献
97.
Diffusion-weighted MR imaging findings in a patient with herpes simplex encephalitis 总被引:5,自引:0,他引:5
INTRODUCTION: Herpes simplex meningoencephalitis is one of the most common viral central nervous system infection in adults. Early diagnosis is essential for treatment. CASE REPORT: We present a case of a 68-year-old female patient with herpes simplex infection. On admission, she was in severe clinical condition. Diffusion-weighted (DW) magnetic resonance imaging detected brain involvement better than conventional sequences. After acyclovir therapy, the patient fully recovered. CONCLUSION: DW magnetic resonance imaging is expected to provide a more sensitive imaging in herpes simplex patients than conventional sequences. 相似文献
98.
Spranger J Kroke A Möhlig M Hoffmann K Bergmann MM Ristow M Boeing H Pfeiffer AF 《Diabetes》2003,52(3):812-817
A subclinical inflammatory reaction has been shown to precede the onset of type 2 (non-insulin-dependent) diabetes. We therefore examined prospectively the effects of the central inflammatory cytokines interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha (TNF-alpha) on the development of type 2 diabetes. We designed a nested case-control study within the prospective population-based European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study including 27,548 individuals. Case subjects were defined to be those who were free of type 2 diabetes at baseline and subsequently developed type 2 diabetes during a 2.3-year follow-up period. A total of 192 cases of incident type 2 diabetes were identified and matched with 384 non-disease-developing control subjects. IL-6 and TNF-alpha levels were found to be elevated in participants with incident type 2 diabetes, whereas IL-1beta plasma levels did not differ between the groups. Analysis of single cytokines revealed IL-6 as an independent predictor of type 2 diabetes after adjustment for age, sex, BMI, waist-to-hip ratio (WHR), sports, smoking status, educational attainment, alcohol consumption, and HbA(1c) (4th vs. the 1st quartile: odds ratio [OR] 2.6, 95% CI 1.2-5.5). The association between TNF-alpha and future type 2 diabetes was no longer significant after adjustment for BMI or WHR. Interestingly, combined analysis of the cytokines revealed a significant interaction between IL-1beta and IL-6. In the fully adjusted model, participants with detectable levels of IL-1beta and elevated levels of IL-6 had an independently increased risk to develop type 2 diabetes (3.3, 1.7-6.8), whereas individuals with increased concentrations of IL-6 but undetectable levels of IL-1beta had no significantly increased risk, both compared with the low-level reference group. These results were confirmed in an analysis including only individuals with HbA(1c) <5.8% at baseline. Our data suggest that the pattern of circulating inflammatory cytokines modifies the risk for type 2 diabetes. In particular, a combined elevation of IL-1beta and IL-6, rather than the isolated elevation of IL-6 alone, independently increases the risk of type 2 diabetes. These data strongly support the hypothesis that a subclinical inflammatory reaction has a role in the pathogenesis of type 2 diabetes. 相似文献
99.
Gerber B Müller H Reimer T Krause A Friese K 《Breast cancer research and treatment》2003,79(2):265-276
Aspects of nutrition and lifestyle may be largely responsible for the development of common cancers in Western countries, as indicated by the large differences in breast cancer rates between countries, the striking changes in these rates among migrating populations, and the rapid changes over time within countries. The better informed and increasingly health-conscious population of the present day are intensively seeking to identify and eliminate these putative carcinogenic risk factors and to exploit the preventive effects that have been attributed to certain dietary components. Nutrition and 'lifestyle' may exert its carcinogenic effects indirectly by cell stimulations (alcohol, hormone therapy in postmenopause), inhibition of DNA-repair mechanisms (lack of vitamins), effecting estrogen metabolism (phytoestrogenes), or as promotors to enhance growth of tumours (body mass index). Some 'substances' may act as a carcinogenic itself, for example, aromatic hydrocarbons in tobacco or increased polycyclic aromatic hydrocarbons in well done meat. Individual differences in the effects of nutritional factors on mammary epithelia could be caused by genetic polymorphisms. In this critical review, we focus on current data regarding the effect of nutrition and lifestyle, on the risk of developing breast cancer. A health lifestyle, consisting of 'healthy diet', physical activity, renunciation of stimulants, is recommended from childhood throughout life. 相似文献
100.
Relationship and differential validity of alexithymia and depression: a comparison of the Toronto Alexithymia and Self-Rating Depression Scales 总被引:2,自引:0,他引:2
Theoretically, the constructs of alexithymia and depression share many common characteristics. Empirically moderate correlations between measures of alexithymia and depression have been found, hence it has been argued that the Toronto Alexithymia Scale (TAS) may be, at least in some part, just another measure for depression. The purpose of this study was to evaluate the construct validity of alexithymia and to analyze the relationship between alexithymia and depression. Exploratory and confirmatory factor analyses were conducted on the combined items of the TAS-20 and the Self-Rating Depression Scale (SDS) in a psychosomatic and alcoholic inpatient sample (n = 199) and a sample of normal adults (controls, n = 174). The exploratory factor analysis in the patient sample yielded a 4-factor structure. Within each factor there was no overlap between the items of the TAS-20 and the SDS. Two factors were comprised of items of the TAS-20 and two factors consisted of items of the SDS. This 4-factor model also showed an acceptable fit for the data of the normal sample in a confirmatory factor analysis. Moderate correlations between the TAS- 20 and SDS total scores and some factors were found. Both instruments, the TAS-20 and the SDS, seem to measure distinct constructs and are not just different measures for the same underlying construct. This provides support for the differential validity of the alexithymia and depression constructs and is in accordance with previous findings. 相似文献