307 research outputs found

    Alteration of cystic airway mesenchyme in congenital pulmonary airway malformation.

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    Congenital pulmonary airway malformation (CPAM) is the most common congenital lesion detected in the neonatal lung, which may lead to respiratory distress, infection, and pneumothorax. CPAM is thought to result from abnormal branching morphogenesis during fetal lung development, arising from different locations within the developing respiratory tract. However, the pathogenic mechanisms are unknown, and previous studies have focused on abnormalities in airway epithelial cells. We have analyzed 13 excised lung specimens from infants (age < 1 year) with a confirmed diagnosis of type 2 CPAM, which is supposed to be derived from abnormal growth of intrapulmonary distal airways. By examining the mesenchymal components including smooth muscle cells, laminin, and elastin in airway and cystic walls using immunofluorescence staining, we found that the thickness and area of the smooth muscle layer underlining the airway cysts in these CPAM tissue sections were significantly decreased compared with those in bronchiolar walls of normal controls. Extracellular elastin fibers were also visually reduced or absent in airway cystic walls. In particular, a layer of elastin fibers seen in normal lung between airway epithelia and underlying smooth muscle cells was missing in type 2 CPAM samples. Thus, our data demonstrate for the first time that airway cystic lesions in type 2 CPAM occur not only in airway epithelial cells, but also in adjacent mesenchymal tissues, including airway smooth muscle cells and their extracellular protein products. This provides a new direction to study the molecular and cellular mechanisms of CPAM pathogenesis in human

    Prolonged mixed phase induced by high pressure in MnRuP

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    Hexagonally structured MnRuP was studied under high pressure up to 35 GPa from 5 to 300 K using synchrotron X-ray diffraction. We observed that a partial phase transition from hexagonal to orthorhombic symmetry started at 11 GPa. The new and denser orthorhombic phase coexisted with its parent phase for an unusually long pressure range, {\Delta}P ~ 50 GPa. We attribute this structural transformation to a magnetic origin, where a decisive criterion for the boundary of the mixed phase lays in the different distances between the Mn-Mn atoms. In addition, our theoretical study shows that the orthorhombic phase of MnRuP remains steady even at very high pressures up to ~ 250 GPa, when it should transform to a new tetragonal phase.Comment: 15 pages, 5 figures, supplementary materia

    Assessing contributions of agricultural and nonagricultural emissions to atmospheric ammonia in a Chinese megacity

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    Ammonia (NH3) is the predominant alkaline gas in the atmosphere contributing to formation of fine particles—a leading environmental cause of increased morbidity and mortality worldwide. Prior findings suggest that NH3 in the urban atmosphere derives from a complex mixture of agricultural (mainly livestock production and fertilizer application) and nonagricultural (e.g., urban waste, fossil fuel-related emissions) sources; however, a citywide holistic assessment is hitherto lacking. Here we show that NH3 from nonagricultural sources rivals agricultural NH3 source contributions in the Shanghai urban atmosphere. We base our conclusion on four independent approaches: (i) a full-year operation of a passive NH3 monitoring network at 14 locations covering urban, suburban, and rural landscapes; (ii) model-measurement comparison of hourly NH3 concentrations at a pair of urban and rural supersites; (iii) source-specific NH3 measurements from emission sources; and (iv) localized isotopic signatures of NH3 sources integrated in a Bayesian isotope mixing model to make isotope-based source apportionment estimates of ambient NH3. Results indicate that nonagricultural sources and agricultural sources are both important contributors to NH3 in the urban atmosphere. These findings highlight opportunities to limit NH3 emissions from nonagricultural sources to help curb PM2.5 pollution in urban China

    Comparative study on the thermoelectric effect of parent oxypnictides LaTTAsO (TT = Fe, Ni)

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    The thermopower and Nernst effect were investigated for undoped parent compounds LaFeAsO and LaNiAsO. Both thermopower and Nernst signal in iron-based LaFeAsO are significantly larger than those in nickel-based LaNiAsO. Furthermore, abrupt changes in both thermopower and Nernst effect are observed below the structural phase transition temperature and spin-density wave (SDW) type antiferromagnetic (AFM) order temperature in Fe-based LaFeAsO. On the other hand, Nernst effect is very small in the Ni-based LaNiAsO and it is weakly temperature-dependent, reminiscent of the case in normal metals. We suggest that the effect of SDW order on the spin scattering rate should play an important role in the anomalous temperature dependence of Hall effect and Nernst effect in LaFeAsO. The contrast behavior between the LaFeAsO and LaNiAsO systems implies that the LaFeAsO system is fundamentally different from the LaNiAsO system and this may provide clues to the mechanism of high TcT_c superconductivity in the Fe-based systems.Comment: 6 pages, 6 figure

    Genomic study of the response of chicken to highly pathogenic avian influenza virus

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    <p>Abstract</p> <p>Background</p> <p>The host mounts an immune response to pathogens, but few data are currently available on the role of host genetics in variation in response to avian influenza (AI). The study presented here investigated the role of the host genetic background in response to <it>in vivo</it> infection with AI virus (AIV).</p> <p>Methods</p> <p>Experimental lines of chicken and commercial crosses were experimentally infected intratracheally with 10<sup>3</sup> EID<sub>50</sub>/bird of A/Chicken/Italy/13474/99 H7N1 highly pathogenic avian influenza virus (HPAIV). Chickens were genotyped for the <it>Mx</it> polymorphism causing the S631N mutation, and for the Major Histocompatibility Complex (MHC). Whole-genome genotyping was carried out using 60 k Single Nucleotide Polymorphism (SNP) array developed by the poultry Genome-Wide Marker-Assisted Selection Consortium (GWMASC).</p> <p>Results</p> <p>Variability in response of different chicken lines to the HPAIV infections and some degree of resistance to AI were observed: a statistically significant effect of chicken line on the response to infection was found. There was no association between survival in healthy conditions and polymorphisms at the <it>Mx</it> gene and the MHC-<it>B</it> region. The analysis based on the 60 k SNPs provided a good clustering of the chicken lines, but no specific genetic cluster associated with response to AIV was identified.</p> <p>Conclusions</p> <p>Neither the genotype at the <it>Mx</it> gene or MHC-<it>B</it> locus, nor for SNP spanning the whole-genome identified loci involved in variations to response to AIV infection. These results point towards the possibility that either the genetic factors affecting the response of chickens to the H7N1 HPAIV are weak, or relevant alleles were not segregating in the studied populations.</p

    What is the prevalence of fear of cancer recurrence in cancer survivors and patients? A systematic review and individual participant data meta-analysis

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    This study was supported by the Dutch Cancer Society (KWF) grant number 10936.Objective Care for fear of cancer recurrence (FCR) is considered the most common unmet need among cancer survivors. Yet the prevalence of FCR and predisposing factors remain inconclusive. To support targeted care, we provide a comprehensive overview of the prevalence and severity of FCR among cancer survivors and patients, as measured using the short form of the validated Fear of Cancer Recurrence Inventory (FCRI-SF). We also report on associations between FCR and clinical and demographic characteristics. Methods This is a systematic review and individual participant data (IPD) meta-analysis on the prevalence of FCR. In the review, we included all studies that used the FCRI-SF with adult (≥18 years) cancer survivors and patients. Date of search: 7 February 2020. Risk of bias was assessed using the Joanna Briggs Institute critical appraisal tool. Results IPD were requested from 87 unique studies and provided for 46 studies comprising 11,226 participants from 13 countries. 9311 respondents were included for the main analyses. On the FCRI-SF (range 0–36), 58.8% of respondents scored ≥13, 45.1% scored ≥16 and 19.2% scored ≥22. FCR decreased with age and women reported more FCR than men. FCR was found across cancer types and continents and for all time periods since cancer diagnosis. Conclusions FCR affects a considerable number of cancer survivors and patients. It is therefore important that healthcare providers discuss this issue with their patients and provide treatment when needed. Further research is needed to investigate how best to prevent and treat FCR and to identify other factors associated with FCR. The protocol was prospectively registered (PROSPERO CRD42020142185).Publisher PDFPeer reviewe
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