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1.
Resulting from the knowledge that cyanobacteria (blue-green algae) are able to produce pharmacologically active substances the aqueous extracts from several cyanobacteria species and strains (Microcystis aeruginosa, Synechocystis aquatilis, Oscillatoria redekei, Anabaena flos-aque, Aphanizomenon flos-aquae, Oscillatoria rubescens, Oscillatoria tenuis) were tested for their immunomodulating activity. Extracts from Oscillatoria redekei 051, Oscillatoria tenuis 01 and Synechocystis aquatilis 428 caused an immunosuppression. They inhibited not only the incorporation of 3H-thymidine into mitogen stimulated lymphocytes but reduced also the number of plaque-forming cells of mice as shown by hemolysis-plaque-assay. Only extracts from Oscillatoria redekei 051 did not show any cytotoxic effects in lymphocyte cytotoxic test. This may be an evidence for a specific action on the proliferation of lymphocytes.  相似文献   
2.
Pathogenesis of nodular goiter and its implications for surgical management   总被引:2,自引:0,他引:2  
Despite sufficient iodine supply, goiter continues to be of considerable surgical significance in formerly endemic countries. It now appears that iodine deficiency and increased thyrotropin stimulation are not the only causes of goiter. Xenotransplantation of human thyroid tissue onto nude mice allowed study of the regulation of growth and function in human goiter tissue. Grafts of human thyroid tissue growing in nude mice could be shown to react to endogenous mouse thyrotropic stimulation and suppression. 131I autoradiographs of xenotransplanted goiter tissue showed as marked a heterogeneity as did the original goitrous tissue prior to transplantation. There was no firm correlation between the morphologic appearance of a follicle and its iodine metabolism. Scintigraphically "cold" and "hot" goiter tissue differed from each other quantitatively but not qualitatively; i.e., both "hot" and "cold" tissue were composed of metabolically active and nonactive follicles. Iodine organification was not completely suppressible by thyroxine treatment; this indicates autonomous functional activity. The distribution of proliferating tissue labeled by 3-H-thymidine did not parallel the distribution of functionally active tissue labelled by 131I. Thyroxine treatment did not completely inhibit 3-H-thymidine incorporation, indicating autonomous growth. Thus, our pathogenetic concept of goiter formation is based on three mainstays: (1) goiter heterogeneity, (2) autonomy of growth and function, and (3) dissociation of growth and function in human goiter tissue. Thus, the surgeon dealing with goiter ought to remove all pathologically altered tissue, i.e., nodular tissue, irrespective of its appearance on scintiscans.  相似文献   
3.
Several quantitative trait loci regulating murine Lyme arthritis severity have been mapped, including a highly significant linkage found on chromosome 5, termed Bb2Bb3. Within this region, the Ncf1 gene of the phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase has recently been identified as a major regulator of arthritis severity in rodent models of rheumatoid arthritis, an effect attributed to protective properties of reactive oxygen species. To assess the role of Ncf1 in Lyme arthritis, we introgressed Bb2Bb3 from severely arthritic C3H/He mice onto mildly arthritic C57BL/6 mice. This increased Lyme arthritis severity, whereas the reciprocal transfer conferred protection from disease. A single nucleotide polymorphism was identified in the Ncf1 gene that did not influence the protein sequence or expression of Ncf1. Although polymorphonuclear leukocytes from C57BL/6 mice generated a greater oxidative burst than polymorphonuclear leukocytes from C3H/He mice, studies with the Bb2Bb3 congenic mice demonstrated this difference was not linked to Ncf1 alleles. Furthermore, Lyme arthritis severity was not altered in mice lacking either the Ncf1 or Gp91phox subunits of the NADPH oxidase complex. Together, these results argue that Ncf1 is not a candidate gene for regulation of Lyme arthritis and reveal Lyme arthritis to be independent of NADPH oxidase activity, distinguishing it from other models of rheumatoid arthritis.  相似文献   
4.
Autoimmunity to Spermatozoa and the Testis   总被引:2,自引:0,他引:2  
  相似文献   
5.
The present study aims to evaluate the effects of an infant formula supplemented with a mixture of prebiotic short and long chain inulin-type oligosaccharides on health outcomes, safety and tolerance, as well as on fecal microbiota composition during the first year of life. In a prospective, multicenter, randomized, double-blind study, n = 160 healthy term infants under 4 months of age were randomized to receive either an infant formula enriched with 0.8 g/dL of Orafti®Synergy1 or an unsupplemented control formula until the age of 12 months. Growth, fever (>38 °C) and infections were regularly followed up by a pediatrician. Digestive symptoms, stool consistency as well as crying and sleeping patterns were recorded during one week each study month. Fecal microbiota and immunological biomarkers were determined from a subgroup of infants after 2, 6 and 12 months of life. The intention to treat (ITT) population consisted of n = 149 infants. Both formulae were well tolerated. Mean duration of infections was significantly lower in the prebiotic fed infants (p < 0.05). The prebiotic group showed higher Bifidobacterium counts at month 6 (p = 0.006), and higher proportions of Bifidobacterium in relation to total bacteria at month 2 and 6 (p = 0.042 and p = 0.013, respectively). Stools of infants receiving the prebiotic formula were softer (p < 0.05). Orafti®Synergy1 tended to beneficially impact total daily amount of crying (p = 0.0594). Supplementation with inulin-type prebiotic oligosaccharides during the first year of life beneficially modulates the infant gut microbiota towards higher Bifidobacterium levels at the first 6 months of life, and is associated with reduced duration of infections.  相似文献   
6.
Intracellularly persistent group A streptococci (GAS, Streptococcus pyogenes) have been associated with recurrent tonsillopharyngitis and antibiotic treatment failure. As a supplementation of the published in vitro data, conventional bacteriology and molecular epidemiology was performed on material from 29 adult patients of a German army hospital with anamnestic signs of recurrent tonsillopharyngitis. Pre-surgery tonsil swabs and the surgically removed tonsils were examined with respect to growth of aerobic bacteria in absence and presence of antibiotics with exclusively extracellular activity. Under such antibiotic selection, Staphylococcus aureus and GAS were cultured from specimens of 13 and 3 patients, respectively. In every material GAS-positive by culture methods, the intracellular location of the penicillin-susceptible GAS isolates was confirmed by immunohistologic examination of tonsillar sections using a GAS-specific IgG antibody. The three intracellular GAS isolates were typed by emm gene sequencing and could be associated to types M6 and M49 (two isolates). The bacteria were serially passaged on sheep blood agar, and semiquantitative mRNA analysis from virulence genes was performed using bacteria of the 4th and 25th passage after isolation. An M-type-specific pattern of virulence gene expression and different gene expression levels in relation to the passage number were observed.  相似文献   
7.
Cicutoxin, the convulsant principle of water hemlock, Cicuta virosa L., and the related polyacetylenes isocicutoxin, cicudiol, cicutol, falcarindiol, and falcarinol (20-100 micromol/l) were investigated concerning their influence on electrophysiological parameters using the giant cell RPD1 of the right parietal ganglion of the pond snail, Lymnaea stagnalis L., as a model neurone. Action potentials occurring spontaneously in this cell were recorded by the intracellular microelectrode technique. The duration of depolarisation, the duration of repolarisation, and the amplitude of the action potentials were determined before and after addition of test substances. Cicutoxin increased the duration of repolarisation dose-dependently up to sixfold at 100 micromol/l. Isocicutoxin caused a prolongation of the repolarisation phase up to twofold at 60 micromol/l, but its effect was reduced at 100 micromol/l. The other polyacetylenes tested did not show any effects on the parameters measured. It is concluded that a molecule with two hydroxy groups separated by a rigid hydrocarbon chain of a certain length is required for the described action. The action potential prolongation provoked by cicutoxin could be responsible for the toxicity of the substance in vertebrates.  相似文献   
8.
9.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - In Deutschland ist seit 2010 die Auseinandersetzung um sexuelle Gewalterfahrungen, auch über die umfangreichen...  相似文献   
10.
BackgroundThe doubling of the number of people with dementia in the coming decades coupled with the rapid decline in the working population in our graying society is expected to result in a large decrease in the number of professionals available to provide care to people with dementia. As a result, care will be supplied increasingly by untrained informal caregivers and volunteers. To promote effective care and avoid overburdening of untrained and trained caregivers, they must become properly skilled. To this end, the European Skills Training and Reskilling (STAR) project, which comprised experts from the domains of education, technology, and dementia care from 6 countries (the Netherlands, Sweden, Italy, Malta, Romania, and the United Kingdom), worked together to create and evaluate a multilingual e-learning tool. The STAR training portal provides dementia care training both for informal and formal caregivers.ObjectiveThe objective of the current study was to evaluate the user friendliness, usefulness, and impact of STAR with informal caregivers, volunteers, and professional caregivers.MethodsFor 2 to 4 months, the experimental group had access to the STAR training portal, a Web-based portal consisting of 8 modules, 2 of which had a basic level and 6 additional modules at intermediate and advanced levels. The experimental group also had access to online peer and expert communities for support and information exchange. The control group received free access to STAR after the research had ended. The STAR training portal was evaluated in a randomized controlled trial among informal caregivers and volunteers in addition to professional caregivers (N=142) in the Netherlands and the United Kingdom. Assessments were performed with self-assessed, online, standardized questionnaires at baseline and after 2 to 4 months. Primary outcome measures were user friendliness, usefulness, and impact of STAR on knowledge, attitudes, and approaches of caregivers regarding dementia. Secondary outcome measures were empathy, quality of life, burden, and caregivers’ sense of competence.ResultsSTAR was rated positively by all user groups on both usefulness and user friendliness. Significant effects were found on a person-centered care approach and on the total score on positive attitudes to dementia; both the experimental and the control group increased in score. Regarding empathy, significant improvements were found in the STAR training group on distress, empathic concern, and taking the perspective of the person with dementia. In the experimental group, however, there was a significant reduction in self-reported sense of competence.ConclusionsThe STAR training portal is a useful and user-friendly e-learning method, which has demonstrated its ability to provide significant positive effects on caregiver attitudes and empathy.  相似文献   
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