1,064 research outputs found

    Carbon and nitrogen fixation and metabolite exchange in and between individual cells of Anabaena oscillarioides

    Get PDF
    Filamentous nitrogen fixing cyanobacteria are key players in global nutrient cycling, but the relationship between CO"2- and N"2-fixation and intercellular exchange of these elements remains poorly understood in many genera. Using high-resolution nanometer-scale secondary ion mass spectrometry (NanoSIMS) in conjunction with enriched H13CO"3- and 15N"2 incubations of Anabaena oscillarioides, we imaged the cellular distributions of C, N and P and 13C and 15N enrichments at multiple time points during a diurnal cycle as proxies for C and N assimilation. The temporal and spatial distributions of the newly fixed C and N were highly heterogeneous at both the intra- and inter-cellular scale, and indicative of regions performing active assimilation and biosynthesis. Subcellular components such as the neck region of heterocycts, cell division septae and putative cyanophycin granules were clearly identifiable by their elemental composition. Newly fixed nitrogen was rapidly exported from heterocysts and was evenly allocated among vegetative cells, with the exception of the most remote vegetative cells between heterocysts, which were N limited based on lower 15N enrichment. Preexisting functional heterocysts had the lowest levels of 13C and 15N enrichment, while heterocysts that were inferred to have differentiated during the experiment had higher levels of enrichment. This innovative approach, combining stable isotope labeling and NanoSIMS elemental and isotopic imaging, allows characterization of cellular development (division, heterocyst differentiation), changes in individual cell composition and cellular roles in metabolite exchange

    SIGN-R1 Contributes to Protection against Lethal Pneumococcal Infection in Mice

    Get PDF
    Rapid clearance of pathogens is essential for successful control of pyogenic bacterial infection. Previous experiments have shown that antibody to specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1 inhibits uptake of capsular polysaccharide by marginal zone macrophages, suggesting a role for SIGN-R1 in this process. We now demonstrate that mice lacking SIGN-R1 (a mouse homologue of human dendritic cell–SIGN receptor) are significantly more susceptible to Streptococcus pneumoniae infection and fail to clear S. pneumoniae from the circulation. Marginal zone and peritoneal macrophages show impaired bacterial recognition associated with an inability to bind T-independent type 2 antigens such as dextran. Our work represents the first evidence for a protective in vivo role for a SIGN family molecule

    “How Long Have I Got?”—A Prospective Cohort Study Comparing Validated Prognostic Factors for Use in Patients with Advanced Cancer

    Get PDF
    © AlphaMed Press 2019 Background: The optimal prognostic factors in patients with advanced cancer are not known, as a comparison of these is lacking. The aim of the present study was to determine the optimal prognostic factors by comparing validated factors. Materials and Methods: A multicenter, prospective observational cohort study recruited patients over 18 years with advanced cancer. The following were assessed: clinician-predicted survival (CPS), Eastern Cooperative Oncology Group performance status (ECOG-PS), patient reported outcome measures (anorexia, cognitive impairment, dyspnea, global health), metastatic disease, weight loss, modified Glasgow Prognostic Score (mGPS) based on C-reactive protein and albumin, lactate dehydrogenase (LDH), and white (WCC), neutrophil (NC), and lymphocyte cell counts. Survival at 1 and 3 months was assessed using area under the receiver operating curve and logistic regression analysis. Results: Data were available on 478 patients, and the median survival was 4.27 (1.86–7.03) months. On univariate analysis, the following factors predicted death at 1 and 3 months: CPS, ECOG-PS, mGPS, WCC, NC (all

    Particle-hole excited states in 133 Te

    Get PDF
    Excited states in neutron-rich 133Te{}^{133}\mathrm{Te} have been identified with the Gamma sphere array by measuring three- and higher-fold prompt coincidence events following spontaneous fission of 252Cf.{}^{252}\mathrm{Cf}. Four types of particle-hole bands built on the known 334.3 keV isomer in 133Te{}^{133}\mathrm{Te} are identified. The yrast and near yrast particle-hole states observed up to 6.2 MeV in 133Te{}^{133}\mathrm{Te} have characteristics quite similar to those in 134Te.{}^{134}\mathrm{Te}. These states are interpreted as a result of coupling a neutron \ensuremath{\nu}{h}_{11/2} hole to the 134Te{}^{134}\mathrm{Te} core. The group of states observed above 5.214 MeV is the result of a neutron particle-hole excitation of the double magic core nucleus 132Sn,{}^{132}\mathrm{Sn}, and is a candidate for a tilted rotor band. Shell-model calculations considering 132Sn{}^{132}\mathrm{Sn} as a closed core have been performed and have provided guidance to the interpretation of the levels below 4.3 MeV. Very good agreement between theory and experiment is obtained for these states

    Prognostic Tools in Patients with Advanced Cancer: A Systematic Review

    Get PDF
    Purpose: In 2005, the European Association for Palliative Care (EAPC) made recommendations for prognostic markers in advanced cancer. Since then, prognostic tools have been developed, evolved and validated. The aim of this systematic review was to examine the progress in the development and validation of prognostic tools. Methods: Medline, Embase Classic + and Embase were searched. Eligible studies met the following criteria: patients with incurable cancer; >18 years; original studies; population n>100; published after 2003. Descriptive and quantitative statistical analyses were performed. Results: Forty-nine studies were eligible, assessing seven prognostic tools across different care settings, primary cancer types and statistically assessed survival prediction. The (PPS) Palliative Performance Scale was the most studied (n=21,082), composed of 6 parameters (6 subjective), was externally validated and predicted survival. The Palliative Prognostic Score (PaP) composed of 6 parameters (4 subjective, 2 objective), the Palliative Prognostic Index (PPI) composed of 9 parameters (9 subjective), and the Glasgow Prognostic Score (GPS) composed of 2 parameters (2 objective), and were all externally validated in more than 2000 patients with advanced cancer and predicted survival. Conclusion: Various prognostic tools have been validated, but vary in their complexity, subjectivity and therefore clinical utility. The GPS would seem the most favourable as it uses only two parameters (both objective) and has prognostic value complementary to the gold standard measure, which is performance status. Further studies comparing all proven prognostic markers in a single cohort of patients with advanced cancer, are needed to determine the optimal prognostic tool

    Decay and Fission Hindrance of Two- and Four-Quasiparticle K Isomers in (254)Rf

    Get PDF
    Two isomers decaying by electromagnetic transitions with half-lives of 4.7(1.1) and 247(73)μs have been discovered in the heavy Rf254 nucleus. The observation of the shorter-lived isomer was made possible by a novel application of a digital data acquisition system. The isomers were interpreted as the Kπ=8-, ν2(7/2+[624],9/2-[734]) two-quasineutron and the Kπ=16+, 8-ν2(7/2+[624],9/2-[734])⊗ - 8-π2(7/2-[514],9/2+[624]) four-quasiparticle configurations, respectively. Surprisingly, the lifetime of the two-quasiparticle isomer is more than 4 orders of magnitude shorter than what has been observed for analogous isomers in the lighter N=150 isotones. The four-quasiparticle isomer is longer lived than the Rf254 ground state that decays exclusively by spontaneous fission with a half-life of 23.2(1.1)μs. The absence of sizable fission branches from either of the isomers implies unprecedented fission hindrance relative to the ground state

    Vascular mechanisms of post-COVID-19 conditions: rho-kinase is a novel target for therapy

    Get PDF
    BackgroundIn post-COVID-19 conditions (Long COVID), systemic vascular dysfunction is implicated but the mechanisms are uncertain, and treatment is imprecise.MethodsPatients convalescing after hospitalisation for COVID-19 and risk-factor matched controls underwent multisystem phenotyping using blood biomarkers, cardiorenal and pulmonary imaging, and gluteal subcutaneous biopsy (NCT04403607). Small resistance arteries were isolated and examined using wire myography, histopathology, immunohistochemistry, and spatial transcriptomics. Endothelium-independent (sodium nitroprusside) and -dependent (acetylcholine) vasorelaxation and vasoconstriction to the thromboxane A2 receptor agonist, U46619, and endothelin-1 (ET-1) in the presence or absence of a RhoA/Rho-kinase inhibitor (fasudil), were investigated.ResultsThirty-seven patients, including 27 (mean age 57 years, 48% women, 41% cardiovascular disease) three months post-COVID-19 and 10 controls (mean age 57 years, 20% women, 30% cardiovascular disease), were included. Compared with control responses, U46619-induced constriction was increased (p = 0.002) and endothelium-independent vasorelaxation was reduced in arteries from COVID-19 patients (p < 0.001). This difference was abolished by fasudil. Histopathology revealed greater collagen abundance in COVID-19 arteries (Masson's Trichrome (MT) 69.7% [95%CI: 67.8, 71.7]; picrosirius red 68.6% [95% CI: 64.4, 72.8]) versus controls (MT 64.9% [95%CI:59.4, 70.3] [p = 0.028]; picrosirius red 60.1% [95% CI: 55.4, 64.8], [p = 0.029]). Greater phosphorylated myosin light chain antibody-positive staining in vascular smooth muscle cells was observed in COVID-19 arteries (40.1%; 95% CI: 30.9, 49.3) vs. controls (10.0%; 95% CI: 4.4, 15.6) (p < 0.001). In proof-of-concept studies, gene pathways associated with extracellular matrix alteration, proteoglycan synthesis, and viral mRNA replication appeared to be upregulated.ConclusionPatients with post-COVID-19 conditions have enhanced vascular fibrosis and myosin light change phosphorylation. Rho-kinase activation represents a novel therapeutic target for clinical trials

    Multivariable regression analysis in Schistosoma mansoni-infected individuals in the Sudan reveals unique immunoepidemiological profiles in uninfected, egg+ and non-egg+ infected individuals

    Get PDF
    Background: In the Sudan, Schistosoma mansoni infections are a major cause of morbidity in schoolaged children and infection rates are associated with available clean water sources. During infection, immune responses pass through a Th1 followed by Th2 and Treg phases and patterns can relate to different stages of infection or immunity. Methodology: This retrospective study evaluated immunoepidemiological aspects in 234 individuals(range 4–85 years old) from Kassala and Khartoum states in 2011. Systemic immune profiles(cytokines and immunoglobulins) and epidemiological parameters were surveyed in n = 110 persons presenting patent S. mansoni infections (egg+), n = 63 individuals positive for S. mansoni via PCR in sera but egg negative (SmPCR+) and n = 61 people who were infection-free (Sm uninf). Immunoepidemiological findings were further investigated using two binary multivariable regression analysis. Principal Findings: Nearly all egg+ individuals had no access to latrines and over 90% obtained water via the canal stemming from the Atbara River. With regards to age, infection and an egg+ status was linked to young and adolescent groups. In terms of immunology, S. mansoni infection per se was strongly associated with increased SEA-specific IgG4 but not IgE levels. IL-6, IL-13 and IL-10 were significantly elevated in patently-infected individuals and positively correlated with egg load. In contrast, IL-2 and IL-1β were significantly lower in SmPCR+ individuals when compared to Sm uninf and egg+ groups which was further confirmed during multivariate regression analysis. Conclusions/Significance: Schistosomiasis remains an important public health problem in the Sudan with a high number of patent individuals. In addition, SmPCR diagnostics revealed another cohort of infected individuals with a unique immunological profile and provides an avenue for future studies on non-patent infection states. Future studies should investigate the downstream signalling pathways/mechanisms of IL-2 and IL-1β as potential diagnostic markers in order to distinguish patent from non-patent individuals

    Prognosis in advanced lung cancer - a prospective study of examining key clinicopathological factors

    Get PDF
    AbstractObjectivesIn patients with advanced incurable lung cancer deciding as to the most appropriate treatment (e.g. chemotherapy or supportive care only) is challenging. In such patients the TNM classification system has reached its ceiling therefore other factors are used to assess prognosis and as such, guide treatment. Performance status (PS), weight loss and inflammatory biomarkers (Glasgow Prognostic Score (mGPS)) predict survival in advanced lung cancer however these have not been compared. This study compares key prognostic factors in advanced lung cancer.Materials and methodsPatients with newly diagnosed advanced lung cancer were recruited and demographics, weight loss, other prognostic factors (mGPS, PS) were collected. Kaplan–Meier and Cox regression methods were used to compare these prognostic factors.Results390 patients with advanced incurable lung cancer were recruited; 341 were male, median age was 66 years (IQR 59–73) and patients had stage IV non-small cell (n=288) (73.8%) or extensive stage small cell lung cancer (n=102) (26.2%). The median survival was 7.8 months. On multivariate analysis only performance status (HR 1.74 CI 1.50–2.02) and mGPS (HR 1.67, CI 1.40–2.00) predicted survival (p<0.001). Survival at 3 months ranged from 99% (ECOG 0–1) to 74% (ECOG 2) and using mGPS, from 99% (mGPS0) to 71% (mGPS2). In combination, survival ranged from 99% (mGPS 0, ECOG 0–1) to 33% (mGPS2, ECOG 3).ConclusionPerformance status and the mGPS are superior prognostic factors in advanced lung cancer. In combination, these improved survival prediction compared with either alone
    corecore