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91.
Infectious agents have been proposed to influence susceptibility to autoimmune diseases such as multiple sclerosis. We induced a Th1-mediated central nervous system (CNS) autoimmune disease, experimental autoimmune encephalomyelitis (EAE) in mice with an ongoing infection with Mycobacterium bovis strain bacillus Calmette-Guérin (BCG) to study this possibility. C57BL/6 mice infected with live BCG for 6 weeks were immunized with myelin oligodendroglial glycoprotein peptide (MOG(35-55)) to induce EAE. The clinical severity of EAE was reduced in BCG-infected mice in a BCG dose-dependent manner. Inflammatory-cell infiltration and demyelination of the spinal cord were significantly lessened in BCG-infected animals compared with uninfected EAE controls. ELISPOT and gamma interferon intracellular cytokine analysis of the frequency of antigen-specific CD4(+) T cells in the CNS and in BCG-induced granulomas and adoptive transfer of MOG(35-55)-specific green fluorescent protein-expressing cells into BCG-infected animals indicated that nervous tissue-specific (MOG(35-55)) CD4(+) T cells accumulate in the BCG-induced granuloma sites. These data suggest a novel mechanism for infection-mediated modulation of autoimmunity. We demonstrate that redirected trafficking of activated CNS antigen-specific CD4(+) T cells to local inflammatory sites induced by BCG infection modulates the initiation and progression of a Th1-mediated CNS autoimmune disease.  相似文献   
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Gliding saves much energy, and to make large distances using only this form of flight represents a great challenge for both birds and people. The solution is to make use of the so-called thermals, which are localized, warmer regions in the atmosphere moving upwards with a speed exceeding the descent rate of bird and plane. Whereas birds use this technique mainly for foraging, humans do it as a sporting activity. Thermalling involves efficient optimization including the skilful localization of thermals, trying to guess the most favorable route, estimating the best descending rate, etc. In this study, we address the question whether there are any analogies between the solutions birds and humans find to handle the above task. High-resolution track logs were taken from thermalling falcons and paraglider pilots to determine the essential parameters of the flight patterns. We find that there are relevant common features in the ways birds and humans use thermals. In particular, falcons seem to reproduce the MacCready formula widely used by gliders to calculate the best slope to take before an upcoming thermal.  相似文献   
94.

Aims

The drug-metabolizing capacity of transplanted liver highly influences drug efficacy or toxicity, particularly in the early postoperative period. The aim of our study was to predict therapeutic failures or severe adverse drug reactions by phenotyping for cytochrome P450 (P450) polymorphism resulting in reduced or no activity of the key drug-metabolizing enzymes.

Methods

A validated analytical system with metabolomic tools has been developed for estimation of the drug-metabolizing capacity of transplanted liver, which allows the prediction of potential poor metabolizer phenotypes of donors and facilitates improvement of the individual recipient therapy.

Results

Of the 109 liver donors in Hungary, the frequency of poor metabolizers was found to be 0.92%, 5.5% and 8.3% for CYP2C9, CYP2C19 and CYP2D6, respectively. In the present study, two liver grafts transplanted in paediatric recipients were reported to be poor metabolizer phenotypes. The liver grafts presented normal function in the early postoperative days; 2 weeks after transplantation, however, increasing liver enzymes were detected. Histological investigation of a liver biopsy suggested drug toxicity. The test of drug metabolizing status showed one of the liver grafts to be a CYP2C9 poor metabolizer, and the other was found to be a CYP2C19 poor metabolizer. Rationalization of the medication resulted in the recovery of both the grafts and the recipients within 1 week.

Conclusions

Prospective investigation of the P450 status may lead to the optimization of drug choice and/or dose for a more effective therapy, avoid serious adverse effects, and decrease medical costs. Phenotyping donor livers and tailored medication can contribute to the improvement of graft and recipient survival.

What is already known about this subject

  • The activity of drug-metabolizing enzymes, primarily cytochrome P450 enzymes, can determine a patient''s response to a drug.
  • Therapeutic failure or drug toxicity in the postoperative period after liver transplantation is influenced by the drug metabolizing capacity of the graft.
  • Dose adjustment or selection of an alternative drug, which is not a substrate for the polymorphic enzyme may prevent the development of side-effects in recipients of poor metabolizer liver grafts.

What this study adds

  • A validated analytical system with metabolomic tools has been developed to estimate the drug-metabolizing capacity of transplanted liver, which allows the prediction of potential poor metabolizer phenotypes of donors and facilitates the improvement of individual recipient therapy.
  • In the test of drug-metabolizing status, one of the liver grafts was found to be a CYP2C9 poor metabolizer, while the other was a CYP2C19 poor metabolizer.
  • Rationalization of the medication resulted in the recovery of both the grafts and the recipients within 1 week.
  相似文献   
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97.
Continued diversification and use of new psychoactive substances (NPS) across Europe remains a public health challenge. The study describes health and social consequences of recent NPS use as reported in a survey of marginalised, nightlife and online NPS users in the Netherlands, Hungary, Portugal, Ireland, Germany and Poland (n = 3023). Some respondents were unable to categorise NPS they had used. Use of ‘herbal blends’ and ‘synthetic cannabinoids obtained pure’ was most reported in Germany, Poland and Hungary, and use of ‘branded stimulants’ and ‘stimulants/empathogens/nootropics obtained pure’ was most reported in the Netherlands. Increased heart rate and palpitation, dizziness, anxiety, horror trips and headaches were most commonly reported acute side effects. Marginalised users reported substantially more acute side effects, more mid- and long-term mental and physical problems, and more social problems. Development of country-specific NPS awareness raising initiatives, health and social service needs assessments, and targeted responses are warranted.  相似文献   
98.
IntroductionAccelerated antibody-mediated rejection is a major challenge after kidney transplantation. While the clinical course, diagnosis, and treatment of cell-mediated acute rejection is agreed upon and has been successfully performed, the antibody-mediated rejection remains a problem. Biopsies cannot be repeated several times, are not always representative, and are refused by many patients. Analysis of T-cell subsets and donor-specific antibodies (DSAs) might be an additive diagnostic tool in the case of kidney transplantation.MethodBetween 2015 and 2017, 50 kidney transplant patients were enrolled in the study. Patients were divided into 2 clinical groups: primary transplants and regrafted patients. Serum samples were collected right before the operation, then in 1 week; 30, 60, and 180 days; and yearly. Besides routine laboratory, multicolor flow cytometry was performed for T cell subsets, and Luminex Single Antigen Bead assay for the detection on donor-specific anti-HLA antibodies. Medical data were also fixed.ResultsThe percentage of CD4+ and CD8+ cells (the CD4+/CD8+ rate) did not change much over time in either group. The percentage of CD19+ cells increased until week 1, then decreased back to its original level by day 180. CD56+/3-% was high in both groups and had no characteristic kinetics by the time. The CD4+ naïve absolute cell count increased in first-time transplants and did not decreased back to its original value until the end of year 1. This is in contrast to retransplants, where CD4+ naïve cell count rapidly dropped below its original value and remained low throughout the first year after transplantation. The CD8+ effector memory absolute cell-count was higher in first-time transplants compared to retransplanted patients in all time points. By the end of month 1, the CD19+ naïve absolute cell-count increased in first-time transplants to 170% of its original value; however, it remained or decreased in second transplants. By the end of the first year, the CD19+ naïve absolute cell count diminished to 70% in first-time transplants and 38% in second transplants. DSA was detected in 9 out of the 38 first-time transplants (23.7%) compared to 7 out of 12 (58.3%) in regrafted patients during the observational period (P = .001). It was typical for regrafted patients for DSAs to appear earlier after transplantation, and that more simultaneously different antibodies were detected against more antigens at the first time point compared to first-time transplants.DiscussionThe 2 groups were similar in demographics and there were no differences regarding the clinical course, complications, or output data. However, we found statistical differences regarding the dynamics of T cell subsets and DSAs. The parallel measurement of CD subsets and DSAs might be a sensitive and useful additive tool in diagnosing subclinical immunologic changes after transplantation.  相似文献   
99.
Forced swim test (FST) is a widely used test for antidepressant development. Depression is a stress related disease, as hormones of the stress-axis can modify mood. However it is not clear, how the appearance of depressive-like behavior (floating) in FST is connected with changes in the stress-hormone levels. We hypothesized, that different manipulations would alter the behavior through changes in stress-hormone levels. First the effect of environmental alterations was studied. Increasing water-temperature enhanced floating time together with a decrease in adrenocorticotropin levels. During the dark phase of the day rats spent more time with floating independently from the actual lighting. Neither the phase nor the actual lighting had significant effect on adrenocorticotropin concentrations with higher corticosterone levels during the dark phase. At greater water depth rats float less but the size of animals had no effect. Water depth did not influence adrenocorticotropin and corticosterone responses, but the size of the rats significantly affected both factors. Secondly, administration of imipramine reduced floating and adrenocorticotropin level without affecting corticosterone. Despite the known connection between depression and stress we did not find a correlation between floating behavior and hormone levels. As an alternative mechanism imipramine-induced heart rate and core body temperature decrease was found by telemetric approach. This study is the first summary in rats examining the effect of wide range of environmental alterations during FST. It seems likely that both brain monoamines and stress-axis take part in the development of depression, but these pathways are regulated independently.  相似文献   
100.
Vascular adhesion protein-1 (VAP-1) controls the adhesion of lymphocytes to endothelial cells and is upregulated at sites of inflammation. Moreover, it expresses amine oxidase activity, due to the sequence identity with semicarbazide-sensitive amine oxidase. Recent studies indicate a significant role for VAP-1 in neovascularization, besides its contribution to inflammation. Pathological blood vessel development in severe ocular diseases (such as diabetes, age-related macula degeneration, trauma and infections) might lead to decreased visual acuity and finally to blindness, yet there is no clear consensus as to its appropriate treatment. In the present case study, the effects of two VAP-1 inhibitors on experimentally induced corneal neovascularization in rabbits were compared with the effects of a known inhibitor of angiogenesis, bevacizumab, an anti-vascular endothelial growth factor antibody. In accordance with recent literature data, the results of the preliminary study reported here indicate that the administration of VAP-1 inhibitors is a potentially valuable therapeutic option in the treatment of corneal neovascularization.  相似文献   
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