Neuroglobin, recently discovered in the brain and in the retina of vertebrates, belongs to the class of hexacoordinate globins, in which the distal histidine coordinates the iron center in both the ...Fe(II) and Fe(III) forms. As for most other hexacoordinate globins, the physiological function of neuroglobin is still unclear, but seems to be related to neuronal survival following acute hypoxia. In this study, we have addressed the question whether human neuroglobin could act as a scavenger of toxic species, such as nitrogen monoxide, peroxynitrite, and hydrogen peroxide, which are generated at high levels in the brain during hypoxia; we have also investigated the kinetics of the reactions of its Fe(III) (metNGB) and Fe(II)NO forms with several reagents. Binding of cyanide or NO. to metNGB follows bi-exponential kinetics, showing the existence of two different protein conformations. In the presence of excess NO., metNGB is converted into NGBFe(II)NO by reductive nitrosylation, in analogy to the reactions of NO. with metmyoglobin and methemoglobin. The Fe(II)NO form of neuroglobin is oxidized to metNGB by peroxynitrite and dioxygen, two reactions that also take place in hemoglobin, albeit at lower rates. In contrast to myoglobin and hemoglobin, metNGB unexpectedly does not generate the cytotoxic ferryl form of the protein upon addition of either peroxynitrite or hydrogen peroxide. Taken together, our data indicate that human neuroglobin may be an efficient scavenger of reactive oxidizing species and thus may play a role in the cellular defense against oxidative stress.
Ecological and human health impairments related to excess nitrogen (N) in streams and rivers remain widespread in the United States (U.S.) despite recent efforts to reduce N pollution. Many studies ...have quantified the relationship between N loads to streams in terms of N mass and N inputs to watersheds; however, N concentrations, rather than loads, are more closely related to impacts on human health and aquatic life. Additionally, concentrations, rather than loads, trigger regulatory responses. In this study, we examined how N concentrations are related to N inputs to watersheds (atmospheric deposition, synthetic fertilizer, manure applied to agricultural land, cultivated biological N fixation, and point sources), land cover characteristics, and stream network characteristics, including stream size and the extent of lakes and reservoirs. N concentration data were collected across the conterminous U.S. during the U.S. Environmental Protection Agency's 2008–09 National Rivers and Streams Assessment (n = 1966). Median watershed N inputs were 15.7 kg N ha−1 yr−1. Atmospheric deposition accounted for over half the N inputs in 49% of watersheds, but watersheds with the highest N input rates were dominated by agriculture-related sources. Total N input to watersheds explained 42% and 38% of the variability in total N and dissolved inorganic N concentrations, respectively. Land cover characteristics were also important predictors, with wetland cover muting the effect of agricultural N inputs on N concentrations and riparian disturbance exacerbating it. In contrast, stream variables showed little correlation with N concentrations. This suggests that terrestrial factors that can be managed, such as agricultural N use practices and wetland or riparian areas, control the spatial variability in stream N concentrations across the conterminous U.S.
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•Summer N concentrations were predicted from N inputs to the landscape and land cover.•Atmospheric deposition, agriculture, and sewage contribute to aquatic N loading.•Climate and stream characteristics explained little spatial variability in stream N.•At a national scale, nitrogen inputs drive concentrations, but interact with land cover.•Aquatic nitrogen impairment may be mitigated by managing inputs and land cover.
We consider a general anisotropic massive SU(N) fermionic model, and investigate its quantum integrability. In particular, by regularizing singular operator products, we derive a system of equations ...resulting in the S-matrix and find some non-trivial solutions. We illustrate our findings on the example of a SU(3) model, and show that the Yang-Baxter equation is satisfied in the massless limit for all coupling constants, while in the massive case the solutions are parameterized in terms of the exceptional solutions to the eight-vertex model.
Summary Background Patients admitted to hospital can acquire multidrug-resistant organisms and Clostridium difficile from inadequately disinfected environmental surfaces. We determined the effect of ...three enhanced strategies for terminal room disinfection (disinfection of a room between occupying patients) on acquisition and infection due to meticillin-resistant Staphylococcus aureus , vancomycin-resistant enterococci, C difficile , and multidrug-resistant Acinetobacter. Methods We did a pragmatic, cluster-randomised, crossover trial at nine hospitals in the southeastern USA. Rooms from which a patient with infection or colonisation with a target organism was discharged were terminally disinfected with one of four strategies: reference (quaternary ammonium disinfectant except for C difficile , for which bleach was used); UV (quaternary ammonium disinfectant and disinfecting ultraviolet UV-C light except for C difficile , for which bleach and UV-C were used); bleach; and bleach and UV-C. The next patient admitted to the targeted room was considered exposed. Every strategy was used at each hospital in four consecutive 7-month periods. We randomly assigned the sequence of strategies for each hospital (1:1:1:1). The primary outcomes were the incidence of infection or colonisation with all target organisms among exposed patients and the incidence of C difficile infection among exposed patients in the intention-to-treat population. This trial is registered with ClinicalTrials.gov , NCT01579370. Findings 31 226 patients were exposed; 21 395 (69%) met all inclusion criteria, including 4916 in the reference group, 5178 in the UV group, 5438 in the bleach group, and 5863 in the bleach and UV group. 115 patients had the primary outcome during 22 426 exposure days in the reference group (51·3 per 10 000 exposure days). The incidence of target organisms among exposed patients was significantly lower after adding UV to standard cleaning strategies (n=76; 33·9 cases per 10 000 exposure days; relative risk RR 0·70, 95% CI 0·50–0·98; p=0·036). The primary outcome was not statistically lower with bleach (n=101; 41·6 cases per 10 000 exposure days; RR 0·85, 95% CI 0·69–1·04; p=0·116), or bleach and UV (n=131; 45·6 cases per 10 000 exposure days; RR 0·91, 95% CI 0·76–1·09; p=0·303) among exposed patients. Similarly, the incidence of C difficile infection among exposed patients was not changed after adding UV to cleaning with bleach (n=38 vs 36; 30·4 cases vs 31·6 cases per 10 000 exposure days; RR 1·0, 95% CI 0·57–1·75; p=0·997). Interpretation A contaminated health-care environment is an important source for acquisition of pathogens; enhanced terminal room disinfection decreases this risk. Funding US Centers for Disease Control and Prevention.
Abstract
We investigate the interplay of magnetization and lattice vibrations in rare-earth orthoferrites
R
FeO
3
, with a specific focus on non-symmetry-breaking anomalies. To do so, we study the ...magnetization, magnon excitations and lattice dynamics as a function of temperature in NdFeO
3
, TbFeO
3
, EuFeO
3
and GdFeO
3
. The magnetization shows distinct temperature anomalous behavior for all investigated rare-earth orthoferrites, even in the compounds with no phase transitions occurring at those temperatures. Through spin–phonon coupling, these magnetic changes are mirrored by the FeO
6
rotation mode for all the studied
R
FeO
3
, revealing a common magnetostructural effect associated with the octahedra rotations. The
R
3+
oscillation modes evidence a Fe
3+
/R
3+
spins cross-talk for the NdFeO
3
and TbFeO
3
cases. Our work sheds light into the common magnetostructural coupling in rare-earth orthoferrites, and the important role of magnetic anisotropy and spin–orbit coupling strength of the
R
–Fe interactions on the spin-reorientation transition at high temperatures.
We integrate a long-lived memory qubit into a mixed-species trapped-ion quantum network node. Ion-photon entanglement first generated with a network qubit in ^{88}Sr^{+} is transferred to ^{43}Ca^{+} ...with 0.977(7) fidelity, and mapped to a robust memory qubit. We then entangle the network qubit with a second photon, without affecting the memory qubit. We perform quantum state tomography to show that the fidelity of ion-photon entanglement decays ∼70 times slower on the memory qubit. Dynamical decoupling further extends the storage duration; we measure an ion-photon entanglement fidelity of 0.81(4) after 10 s.
Background
The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing Guidelines on Allergen Immunotherapy (AIT) for Allergic Rhinoconjunctivitis. To inform the ...development of clinical recommendations, we undertook a systematic review to assess the effectiveness, cost‐effectiveness, and safety of AIT in the management of allergic rhinoconjunctivitis.
Methods
We searched nine international biomedical databases for published, in‐progress, and unpublished evidence. Studies were independently screened by two reviewers against predefined eligibility criteria and critically appraised using established instruments. Our primary outcomes of interest were symptom, medication, and combined symptom and medication scores. Secondary outcomes of interest included cost‐effectiveness and safety. Data were descriptively summarized and then quantitatively synthesized using random‐effects meta‐analyses.
Results
We identified 5960 studies of which 160 studies satisfied our eligibility criteria. There was a substantial body of evidence demonstrating significant reductions in standardized mean differences (SMD) of symptom (SMD −0.53, 95% CI −0.63, −0.42), medication (SMD −0.37, 95% CI −0.49, −0.26), and combined symptom and medication (SMD −0.49, 95% CI −0.69, −0.30) scores while on treatment that were robust to prespecified sensitivity analyses. There was in comparison a more modest body of evidence on effectiveness post‐discontinuation of AIT, suggesting a benefit in relation to symptom scores.
Conclusions
AIT is effective in improving symptom, medication, and combined symptom and medication scores in patients with allergic rhinoconjunctivitis while on treatment, and there is some evidence suggesting that these benefits are maintained in relation to symptom scores after discontinuation of therapy.
Significance The human gut microbiota is a complex community of microbes with enormous metabolic potential. Recognition of the significance of bacterial metabolites in mediating host interactions and ...the impact of perturbations of this ecosystem on human health has increased dramatically. Antibiotic therapy eliminates not only pathogens but also some of the commensal enteric microbiota, sometimes leading to inflammation and diarrhea. Understanding how microbial imbalance actually causes disease is challenging. This study reveals how a gut resident is able to cause colitis during penicillin therapy. We show that a pyrrolobenzodiazepine metabolite produced by Klebsiella oxytoca directly damages the intestinal epithelium and disrupts its protective barrier function. The enterotoxicity of tilivalline provides a mechanism for antibiotic-induced colitis.
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