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1.
E. R. Heise D. J. Cook B. S. Schepart C. H. Manning M. R. McMahan M. Chedid C. A. Keever 《Genetica》1987,73(1-2):53-68
The major histocompatibility complex (MHC) encodes cell surface glycoproteins that function in self-nonself recognition and in allograft rejection. Among primates, the MHC has been well defined only in the human; in the chimpanzee and in two species of macaque monkeys the MHC is less well characterized. Serologic, biochemical and genetic evidence indicates that the basic organization of the MHC linkage group has been phylogenetically conserved. However, the number of genes and their linear relationship on the chromosomes differ between species. Class I MHC loci encode molecules that are the most polymorphic genes known. These molecules are ubiquitous in their tissue distribution and typically are recognized together with nominal antigens by cytotoxic lymphocytes. Class II MHC loci constitute a smaller family of serotypes serving as restricting elements for regulatory T lymphocytes. The distribution of class II antigens is limited mainly to cell types serving immune functions, and their expression is subject to up and down modulation. Class III loci code for components C2, C4 and Factor B (Bf) of the complement system.Interspecies differences in the extent of polymorphism occur, but the significance of this finding in relation to fitness and natural selection is unclear. Detailed information on the structure and regulation of MHC gene expression will be required to understand fully the biologic role of the MHC and the evolutionary relationships between species. Meanwhile, MHC testing has numerous applications to biomedical research, especially in preclinical tissue and organ transplantation studies, the study of disease mechanisms, parentage determination and breeding colony management. In this review, the current status of MHC definition in nonhuman primates will be summarized. Special emphasis is placed on the CyLA system of M. fascicularis which is a major focus in our laboratory. A highly polymorphic cynomolgus MHC has been partially characterized and consists of at least 14 A locus, 11 B locus, 7 C locus class I allelic specificities, 9 Ia-like class II antigens and 6 Bf (class III) variants. 相似文献
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B. Culik D. Adelung M. Heise R. P. Wilson N. R. Coria H. J. Spairani 《Polar Biology》1989,9(6):365-370
Summary Heart rates and activity were monitored over 24 h in unrestrained, incubating Adélie penguins (Pygoscelis adeliae) exposed to natural conditions in the colony. Heart rate (HR in bpm) increased linearly with wind speed (w; range 0–19 m/s): HR = 85.8+1.35 w, but was unrelated (P>0.05) to temperature (-2.5°–6°C), humidity (37%–100%) cloud cover (0–8/8) and estimated solar radiation (0–12). Wind-induced heat loss was apparently compensated to a large degree by increased metabolic activity. Activity (A) measured as frequency of standing per hour, decreased linearly with temperature (t) and wind speed (w): A = 1.651–0.033w–0.090t. After correcting for meteorological influences, heart rate and bird activity showed no diurnal periodicity. When incubating, metabolism and activity of Adélie penguins appear to be mainly governed by climatic variations. 相似文献
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Experiments with resting cells of Acetobacterium woodii were performed to elucidate the coupling ion used by the ATP synthase. A. woodii synthesized ATP in response to an artificial delta pH, indicating the presence of a proton-translocating ATPase. On the other hand, a delta pNa, as well as a proton diffusion potential, could serve as a driving force for ATP synthesis with the latter strictly dependent on Na+. These results are indicative for the presence of a Na(+)-translocating ATP synthase in A. woodii. 相似文献
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Hubert Kolb Kathrin Lückemeyer Tim Heise Christian Herder Nanette C. Schloot Wolfgang Koenig Lutz Heinemann Stephan Martin 《PloS one》2013,8(8)
Background
The hypothesis was tested that the systemic immune milieu in recent-onset type 1 diabetes is associated with residual beta cell function and other metabolic patient characteristics.Methods and Findings
All patients (n = 89, 40% female) of the Diabetes and Atorvastatin (DIATOR) Trial were analyzed at recruitment, i.e. prior to receiving the study medication. Inclusion criteria were insulin dependent diabetes for 2 weeks to 3 months, age range 18–39 years, and islet cell autoantibodies. Blood samples were analyzed for 14 immune mediators by standard methods. Concentrations of all mediators correlated with at least one other mediator (p<0.05, Spearman correlation) giving rise to a network. Interleukin 1 receptor antagonist (IL1-RA) held a central position and was associated with both pro- and anti-inflammatory mediators. Further central elements were the pro-inflammatory mediators CRP and IL-6, the soluble adhesion molecules sICAM-1 and E-selectin, and MCP-4 which held a central position in the chemokine network. The two Th1-associated mediators IFNγ and IP-10 remained outside the network but correlated with each other. All correlations were positive (r = 0.25–0.72), i.e., high levels of pro-inflammatory mediators were accompanied by increased levels of anti-inflammatory mediators. IL-1RA was the only mediator associated with fasting and liquid mixed meal stimulated C-peptide concentrations (r = 0.31 and 0.24, p = 0.003 and 0.025, after adjustment for age, sex, BMI). There were associations between the immune mediator network and BMI (IL-1RA, CRP, IL-6, MCP-4, MIP-1ß) but few or no associations with HbA1c, insulin dose, lipid parameters, age or sex.Conclusions
In patients with recent onset type 1 diabetes, systemic acute phase proteins, cytokines, chemokines and soluble adhesion molecules form a network. Among the few central elements IL-1RA has a dominant role. IL-1RA is associated with all other groups of mediators and is the only mediator which correlates (positively) with residual beta cell function.Trial registration
ClinicalTrials.gov registration number: NCT00974740相似文献7.
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Roberts A Deming D Paddock CD Cheng A Yount B Vogel L Herman BD Sheahan T Heise M Genrich GL Zaki SR Baric R Subbarao K 《PLoS pathogens》2007,3(1):e5
No single animal model for severe acute respiratory syndrome (SARS) reproduces all aspects of the human disease. Young inbred mice support SARS-coronavirus (SARS-CoV) replication in the respiratory tract and are available in sufficient numbers for statistical evaluation. They are relatively inexpensive and easily accessible, but their use in SARS research is limited because they do not develop illness following infection. Older (12- to 14-mo-old) BALB/c mice develop clinical illness and pneumonitis, but they can be hard to procure, and immune senescence complicates pathogenesis studies. We adapted the SARS-CoV (Urbani strain) by serial passage in the respiratory tract of young BALB/c mice. Fifteen passages resulted in a virus (MA15) that is lethal for mice following intranasal inoculation. Lethality is preceded by rapid and high titer viral replication in lungs, viremia, and dissemination of virus to extrapulmonary sites accompanied by lymphopenia, neutrophilia, and pathological changes in the lungs. Abundant viral antigen is extensively distributed in bronchial epithelial cells and alveolar pneumocytes, and necrotic cellular debris is present in airways and alveoli, with only mild and focal pneumonitis. These observations suggest that mice infected with MA15 die from an overwhelming viral infection with extensive, virally mediated destruction of pneumocytes and ciliated epithelial cells. The MA15 virus has six coding mutations associated with adaptation and increased virulence; when introduced into a recombinant SARS-CoV, these mutations result in a highly virulent and lethal virus (rMA15), duplicating the phenotype of the biologically derived MA15 virus. Intranasal inoculation with MA15 reproduces many aspects of disease seen in severe human cases of SARS. The availability of the MA15 virus will enhance the use of the mouse model for SARS because infection with MA15 causes morbidity, mortality, and pulmonary pathology. This virus will be of value as a stringent challenge in evaluation of the efficacy of vaccines and antivirals. 相似文献
10.
Giulia Ferrari Sergio Torres-Rueda Esnat Chirwa Andrew Gibbs Stacey Orangi Edwine Barasa Theresa Tawiah Rebecca Kyerewaa Dwommoh Prah Regis Hitimana Emmanuelle Daviaud Eleonah Kapapa Kristin Dunkle Lori Heise Erin Stern Sangeeta Chatterji Benjamin Omondi Deda Ogum Alangea Rozina Karmaliani Hussain Maqbool Ahmed Khuwaja Rachel Jewkes Charlotte Watts Anna Vassall 《PLoS medicine》2022,19(3)
BackgroundViolence against women and girls (VAWG) is a human rights violation with social, economic, and health consequences for survivors, perpetrators, and society. Robust evidence on economic, social, and health impact, plus the cost of delivery of VAWG prevention, is critical to making the case for investment, particularly in low- and middle-income countries (LMICs) where health sector resources are highly constrained. We report on the costs and health impact of VAWG prevention in 6 countries.Methods and findingsWe conducted a trial-based cost-effectiveness analysis of VAWG prevention interventions using primary data from 5 randomised controlled trials (RCTs) in sub-Saharan Africa and 1 in South Asia. We evaluated 2 school-based interventions aimed at adolescents (11 to 14 years old) and 2 workshop-based (small group or one to one) interventions, 1 community-based intervention, and 1 combined small group and community-based programme all aimed at adult men and women (18+ years old). All interventions were delivered between 2015 and 2018 and were compared to a do-nothing scenario, except for one of the school-based interventions (government-mandated programme) and for the combined intervention (access to financial services in small groups). We computed the health burden from VAWG with disability-adjusted life year (DALY). We estimated per capita DALYs averted using statistical models that reflect each trial’s design and any baseline imbalances. We report cost-effectiveness as cost per DALY averted and characterise uncertainty in the estimates with probabilistic sensitivity analysis (PSA) and cost-effectiveness acceptability curves (CEACs), which show the probability of cost-effectiveness at different thresholds. We report a subgroup analysis of the small group component of the combined intervention and no other subgroup analysis. We also report an impact inventory to illustrate interventions’ socioeconomic impact beyond health. We use a 3% discount rate for investment costs and a 1-year time horizon, assuming no effects post the intervention period. From a health sector perspective, the cost per DALY averted varies between US$222 (2018), for an established gender attitudes and harmful social norms change community-based intervention in Ghana, to US$17,548 (2018) for a livelihoods intervention in South Africa. Taking a societal perspective and including wider economic impact improves the cost-effectiveness of some interventions but reduces others. For example, interventions with positive economic impacts, often those with explicit economic goals, offset implementation costs and achieve more favourable cost-effectiveness ratios. Results are robust to sensitivity analyses. Our DALYs include a subset of the health consequences of VAWG exposure; we assume no mortality impact from any of the health consequences included in the DALYs calculations. In both cases, we may be underestimating overall health impact. We also do not report on participants’ health costs.ConclusionsWe demonstrate that investment in established community-based VAWG prevention interventions can improve population health in LMICs, even within highly constrained health budgets. However, several VAWG prevention interventions require further modification to achieve affordability and cost-effectiveness at scale. Broadening the range of social, health, and economic outcomes captured in future cost-effectiveness assessments remains critical to justifying the investment urgently required to prevent VAWG globally.In a cost-effectiveness study, Dr. Giulia Ferrari and colleagues examine the costs and health impact of prevention of violence against women and girls in six low- and middle-income countries. 相似文献