168 research outputs found
Predicting Spatial Patterns of Sindbis Virus (SINV) Infection Risk in Finland Using Vector, Host and Environmental Data
Pogosta disease is a mosquito-borne infection, caused by Sindbis virus (SINV), which causes epidemics of febrile rash and arthritis in Northern Europe and South Africa. Resident grouse and migratory birds play a significant role as amplifying hosts and various mosquito species, including Aedes cinereus, Culex pipiens, Cx. torrentium and Culiseta morsitans are documented vectors. As specific treatments are not available for SINV infections, and joint symptoms may persist, the public health burden is considerable in endemic areas. To predict the environmental suitability for SINV infections in Finland, we applied a suite of geospatial and statistical modeling techniques to disease occurrence data. Using an ensemble approach, we first produced environmental suitability maps for potential SINV vectors in Finland. These suitability maps were then combined with grouse densities and environmental data to identify the influential determinants for SINV infections and to predict the risk of Pogosta disease in Finnish municipalities. Our predictions suggest that both the environmental suitability for vectors and the high risk of Pogosta disease are focused in geographically restricted areas. This provides evidence that the presence of both SINV vector species and grouse densities can predict the occurrence of the disease. The results support material for public-health officials when determining area-specific recommendations and deliver information to health care personnel to raise awareness of the disease among physicians
Predicting Spatial Patterns of Sindbis Virus (SINV) Infection Risk in Finland Using Vector, Host and Environmental Data
Pogosta disease is a mosquito-borne infection, caused by Sindbis virus (SINV), which causes epidemics of febrile rash and arthritis in Northern Europe and South Africa. Resident grouse and migratory birds play a significant role as amplifying hosts and various mosquito species, including Aedes cinereus, Culex pipiens, Cx. torrentium and Culiseta morsitans are documented vectors. As specific treatments are not available for SINV infections, and joint symptoms may persist, the public health burden is considerable in endemic areas. To predict the environmental suitability for SINV infections in Finland, we applied a suite of geospatial and statistical modeling techniques to disease occurrence data. Using an ensemble approach, we first produced environmental suitability maps for potential SINV vectors in Finland. These suitability maps were then combined with grouse densities and environmental data to identify the influential determinants for SINV infections and to predict the risk of Pogosta disease in Finnish municipalities. Our predictions suggest that both the environmental suitability for vectors and the high risk of Pogosta disease are focused in geographically restricted areas. This provides evidence that the presence of both SINV vector species and grouse densities can predict the occurrence of the disease. The results support material for public-health officials when determining area-specific recommendations and deliver information to health care personnel to raise awareness of the disease among physicians
Circulating metabolites in progression to islet autoimmunity and type 1 diabetes
Aims/hypothesis: Metabolic dysregulation may precede the onset of type 1 diabetes. However, these metabolic disturbances and their specific role in disease initiation remain poorly understood. In this study, we examined whether children who progress to type 1 diabetes have a circulatory polar metabolite profile distinct from that of children who later progress to islet autoimmunity but not type 1 diabetes and a matched control group.Methods: We analysed polar metabolites from 415 longitudinal plasma samples in a prospective cohort of children in three study groups: those who progressed to type 1 diabetes; those who seroconverted to one islet autoantibody but not to type 1 diabetes; and an antibody-negative control group. Metabolites were measured using two-dimensional GC high-speed time of flight MS.Results: In early infancy, progression to type 1 diabetes was associated with downregulated amino acids, sugar derivatives and fatty acids, including catabolites of microbial origin, compared with the control group. Methionine remained persistently upregulated in those progressing to type 1 diabetes compared with the control group and those who seroconverted to one islet autoantibody. The appearance of islet autoantibodies was associated with decreased glutamic and aspartic acids.Conclusions/interpretation: Our findings suggest that children who progress to type 1 diabetes have a unique metabolic profile, which is, however, altered with the appearance of islet autoantibodies. Our findings may assist with early prediction of the disease.</p
A longitudinal plasma lipidomics dataset from children who developed islet autoimmunity and type 1 diabetes
Early prediction and prevention of type 1 diabetes (T1D) are currently unmet medical needs. Previous metabolomics studies suggest that children who develop T1D are characterised by a distinct metabolic profile already detectable during infancy, prior to the onset of islet autoimmunity. However, the specificity of persistent metabolic disturbances in relation T1D development has not yet been established. Here, we report a longitudinal plasma lipidomics dataset from (1) 40 children who progressed to T1D during follow-up, (2) 40 children who developed single islet autoantibody but did not develop T1D and (3) 40 matched controls (6 time points: 3, 6, 12, 18, 24 and 36 months of age). This dataset may help other researchers in studying age-dependent progression of islet autoimmunity and T1D as well as of the age-dependence of lipidomic profiles in general. Alternatively, this dataset could more broadly used for the development of methods for the analysis of longitudinal multivariate data
Effect of Early Feeding on Intestinal Permeability and Inflammation Markers in Infants with Genetic Susceptibility to Type 1 Diabetes: A Randomized Clinical Trial
ObjectivesTo assess whether weaning to an extensively hydrolyzed formula (EHF) decreases gut permeability and/or markers of intestinal inflammation in infants with HLA-conferred diabetes susceptibility, when compared with conventional formula.Study designBy analyzing 1468 expecting biological parent pairs for HLA-conferred susceptibility for type 1 diabetes, 465 couples (32 %) potentially eligible for the study were identified. After further parental consent, 332 babies to be born were randomized at 35th gestational week. HLA genotyping was performed at birth in 309 infants. Out of 87 eligible children, 73 infants participated in the intervention study: 33 in the EHF group and 40 in the control group. Clinical visits took place at 3, 6, 9, and 12 months of age. The infants were provided either EHF or conventional formula whenever breastfeeding was not available or additional feeding was required over the first 9 months of life. The main outcome was the lactulose to mannitol ratio (L/M ratio) at 9 months. The secondary outcomes were L/M ratio at 3, 6, and 12 months of age, and fecal calprotectin and human beta-defensin 2 (HBD-2) levels at each visit.ResultsCompared with controls, the median L/M ratio was lower in the EHF group at 9 months (.006 vs .028; P = .005). Otherwise, the levels of intestinal permeability, fecal calprotectin, and HBD-2 were comparable between the two groups, although slight differences in the age-related dynamics of these markers were observed.ConclusionsIt is possible to decrease intestinal permeability in infancy through weaning to an extensively hydrolyzed formula. This may reduce the early exposure to dietary antigens.Trial registrationClinicaltrials.gov: NCT01735123.AbbreviationsEHFExtensively hydrolyzed formula; IDDMInsulin dependent diabetes mellitus; HBD-2Human beta-defensin 2; L/MLactulose/mannitol; T1DType 1 diabetes</p
Requirements for Membrane Attack Complex Formation and Anaphylatoxins Binding to Collagen-Activated Platelets
The activation of complement during platelet activation is incompletely understood.We sought to explore the formation of C5b-9 and anaphylatoxins binding to collagen-activated platelets.C5b-9, anaphylatoxins C3a, C4a and C5a, and anaphylatoxin receptors C3aR1 and C5aR were measured by flow cytometry and/or confocal microscopy. Platelet microparticles were quantified by flow cytometry, and their C5b-9 content was determined by western blot analyses. In all experiments, sodium citrate was used for blood anticoagulation.C5b-9 rapidly formed on the platelet surface following activation with collagen, TRAP, ADP or A23187, but was surprisingly restricted to a subset of platelets (1 to 15%) independently of P-selectin or phosphatidylserine exposure. Following collagen activation, C5b-9-positive platelets in thrombi were found associated with collagen fibres. C5b-9 formation was obliterated by Mg(2+)-EGTA and significantly reduced by the thrombin inhibitor hirudin (-37%, p<0.05), but was unaffected by chondroitinase, compstatin, SCH79797 (PAR-1 inhibitor), or in the PRP of a MBL-deficient donor. Compstatin and Mg(2+)-EGTA, but not hirudin, SCH79797 or chondroitinase, inhibited the formation of collagen-induced microparticles (-71% and -44%, respectively, p<0.04). These microparticles contained greater amounts of C5b-9 compared with the other agonists. Platelet activation by collagen or convulxin resulted in the strong binding of anaphylatoxins and the exposure of receptors C3aR1 and C5aR (CD88) on their surface.C5b-9 formation on collagen-activated platelets is i) partially controlled by thrombin, ii) restricted to a subset of platelets, and iii) can occur without P-selectin expression or phosphatidylserine exposure. Activated platelets bind anaphylatoxins on their surface and express C3a and C5a receptors, which may contribute to the localization of inflammatory processes during thrombosis
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