599 research outputs found

    Antibody responses to nasopharyngeal carriage of Streptococcus pneumoniae in adults: A longitudinal household study

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    Background. Natural immunity to Streptococcus pneumoniae is thought to be induced by exposure to S. pneumoniae or cross-reactive antigens. No longitudinal studies of carriage of and immune responses to S. pneumoniae have been conducted using sophisticated immunological laboratory techniques.Methods. We enrolled 121 families with young children into this study. Nasopharyngeal (NP) swabs were collected monthly for 10 months from all family members and were cultured in a standard fashion. Cultured S. pneumoniae isolates were serotyped. At the beginning (month 0) and end (month 10) of the study, venous blood was collected from family members 118 years old. Serotype-specific antipolysaccharide immunoglobulin G (IgG) and functional antibody and antibodies to pneumolysin, pneumococcal surface protein A (PspA), and pneumococcal surface antigen A (PsaA) were measured in paired serum samples.Results. Levels of anticapsular IgG increased significantly after carriage of serotypes 9V, 14, 18C, 19F, and 23F by an individual or family member. For serotype 14, a higher level of anticapsular IgG at the beginning of the study was associated with reduced odds of carriage (P = .0006). There was a small (similar to 20%) but significant increase in titers of antibodies to PsaA and pneumolysin but no change in titers of antibody to PspA.Conclusions. Adults respond to NP carriage by mounting anticapsular and weak antiprotein antibody responses, and naturally induced anticapsular IgG can prevent carriage

    The Impact of Mercury Selection and Conjugative Genetic Elements on Community Structure and Resistance Gene Transfer

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    Carriage of resistance genes can underpin bacterial survival, and by spreading these genes between species, mobile genetic elements (MGEs) can potentially protect diversity within microbial communities. The spread of MGEs could be affected by environmental factors such as selection for resistance, and biological factors such as plasmid host range, with consequences for individual species and for community structure. Here we cultured a focal bacterial strain,Pseudomonas fluorescensSBW25, embedded within a soil microbial community, with and without mercury selection, and with and without mercury resistance plasmids (pQBR57 or pQBR103), to investigate the effects of selection and resistance gene introduction on (1) the focal species; (2) the community as a whole; (3) the spread of the introducedmerresistance operon. We found thatP. fluorescensSBW25 only escaped competitive exclusion by other members of community under mercury selection, even when it did not begin with a mercury resistance plasmid, due to its propensity to acquire resistance from the community by horizontal gene transfer. Mercury pollution had a significant effect on community structure, decreasing alpha diversity within communities while increasing beta diversity between communities, a pattern that was not affected by the introduction of mercury resistance plasmids byP. fluorescensSBW25. Nevertheless, the introducedmerAgene spread to a phylogenetically diverse set of recipients over the 5 weeks of the experiment, as assessed by epicPCR. Our data demonstrates how the effects of MGEs can be experimentally assessed for individual lineages, the wider community, and for the spread of adaptive traits.Peer reviewe

    Hospital admissions and surgical treatment of children with lower-limb deficiency in Finland

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    Background and Aims: There are no population-based studies about hospital admissions and need for surgical treatment of congenital lower-limb deficiencies. The aim is to assess the impact children with lower-limb deficiencies pose to national hospital level health-care system. Materials and Methods: A population-based study was conducted using the national Register of Congenital Malformations and Care Register for Health Care. All 185 live births with lower-limb deficiency (1993-2008) were included. Data on hospital care were collected until 31 December 2009 and compared to data on the whole pediatric population (0.9 million) live born in 1993-2008. Results: The whole pediatric population had annually on average 0.10 hospital admissions and the mean length of in-patient care of 0.3 days per child. The respective figures were 1.5 and 5.6 in terminal lower-limb amputations (n = 7), 1.1 and 3.9 in long-bone deficiencies (n = 53), 0.6 and 1.9 in foot deficiencies (n = 26) and 0.4 and 2.6 in toe deficiencies (n = 101). Orthopedic surgery was performed in 72% (5/7) of patients with terminal amputations, in 62% (33/53) of patients with long bone, in 58% (14/24) of patients with foot and in 25% (25/101) of patients in toe deficiencies. Half (54%) of all procedures were orthopedic operations. Conclusion: In congenital lower-limb deficiencies the need of hospital care and the number of orthopedic procedures is multiple-fold compared to whole pediatric population. The burden to the patient and to the families is markedly increased, especially in children with terminal amputations and long-bone deficiencies of lower limbs.Peer reviewe

    Improved Passive Gamma Emission Tomography image quality in the central region of spent nuclear fuel

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    Reliable non-destructive methods for verifying spent nuclear fuel are essential to draw credible nuclear safeguards conclusions from spent fuel. In Finland, spent fuel items are verified prior to the soon starting disposal in a geological repository with Passive Gamma Emission Tomography (PGET), a uniquely accurate method capable of rod-level detection of missing active material. The PGET device consists of two highly collimated detector banks, collecting gamma emission data from a 360 degrees rotation around a fuel assembly. 2D cross-sectional activity and attenuation images are simultaneously computed. We present methods for improving reconstructed image quality in the central parts of the fuel. The results are based on data collected from 2017 to 2021 at the Finnish nuclear power plants with 10 fuel assembly types of varying characteristics, for example burnups from 5.7 to 55 GWd/tU and cooling times from 1.9 to 37 years. Data is acquired in different gamma energy windows, capturing the peaks of Cs-137 (at 662 keV) and Eu-154 (at 1274 keV), abundant isotopes in long-cooled spent nuclear fuel. Data from these gamma energy windows at well-chosen angles are used for higher-quality images, resulting in more accurate detection of empty rod positions. The method is shown to detect partial diversion of nuclear material also in the axial direction, demonstrated with a novel measurement series scanning over the edge of partial-length rods.Peer reviewe

    Rab8, a small GTPase involved in vesicular traffic between the TGN and the basolateral plasma membrane

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    Small GTP-binding proteins of the rab family have been implicated as regulators of membrane traffic along the biosynthetic and endocytic pathways in eukaryotic cells. We have investigated the localization and function of rab8, closely related to the yeast YPT1/SEC4 gene products. Confocal immunofluorescence microscopy and immunoelectron microscopy on filter-grown MDCK cells demonstrated that, rab8 was localized to the Golgi region, vesicular structures, and to the basolateral plasma membrane. Two-dimensional gel electrophoresis showed that rab8p was highly enriched in immuno-isolated basolateral vesicles carrying vesicular stomatitis virus-glycoprotein (VSV-G) but was absent from vesicles transporting the hemagglutinin protein (HA) of influenza virus to the apical cell surface

    New constraints for QCD matter from improved Bayesian parameter estimation in heavy-ion collisions at LHC

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    The transport properties of quark-gluon plasma created in relativistic heavy-ion collisions are quantified by an improved global Bayesian analysis using the CERN Large Hadron Collider Pb-Pb data at root s(NN) = 2.76 and 5.02 TeV. The results show that the uncertainty of the extracted transport coefficients is significantly reduced by including new sophisticated collective flow observables from two collision energies for the first time. This work reveals the stronger temperature dependence of specific shear viscosity, a lower value of specific bulk viscosity, and a higher hadronization switching temperature than in the previous studies. The sensitivity analysis confirms that the precision measurements of higher-order harmonic flow and their correlations are crucial in extracting accurate values of the transport properties. (C) 2022 The Author(s). Published by Elsevier B.V.Peer reviewe

    Inhaled corticosteroids in infants and toddlers attenuate linear growth

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    Päivikki and Sakari Sohlberg Foundation (A.S., U.S.), the Foundation for Pediatric Research (A.S., U.S.), Kuopio University Hospital State Research Funding (A.S., U.S.), and the Finnish Medical Foundation (U.S.)
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