Magnetic Field-Sensitive Radical Pair Dynamics in Polymethylene Ether-Bridged Donor–Acceptor Systems

This is the final version of the article. Available from American Chemical Society via the DOI in this record.Donor–acceptor systems forming exciplexes are versatile models for the study of magnetic field effects (MFEs) on charge recombination reactions. The MFEs originate from singlet–triplet interconversion within transient radical ion pairs (RIPs), which exist in a dynamic equilibrium with the exciplexes. Here, we describe the synthesis and MFEs of the chain-linked N,N-dimethylaniline (DMA)/9-methylanthracene (MAnt) donor–acceptor system MAnt–(CH2)n–O–CH2–CH2–DMA for n = 6, 8, 10, and 16. The MFEs are found to increase with increasing chain length. Effects as large as 37.5% have been observed for the long-chain compound with n = 16. The solvent dependence of the MFEs at magnetic field intensity 75 mT is reported. For the range of solvent static dielectric constants εs = 6.0–36.0, the MFEs go through a maximum for intermediate polarities, for which the direct formation of RIPs prevails and their dissociation and reencounter are balanced. Field-resolved measurements (MARY spectra) are reported for solutions in butyronitrile. The MARY spectra reveal that for n = 8, 10, 16, the average exchange interaction is negligible during the coherent lifetime of the radical pair. However, singlet–triplet dephasing broadens the lineshape; the shorter the linker, the more pronounced this effect is. For n = 6, a dip in the fluorescence intensity reveals a nonzero average exchange coupling of the order of ±5 mT. We discuss the field-dependence in the framework of the semiclassical theory taking spin-selective recombination, singlet–triplet dephasing, and exchange coupling into account. Singlet recombination rates of the order of 0.1 ns–1 and various degrees of singlet–triplet dephasing govern the spin dynamics. In addition, because of a small free energy gap between the exciplex and the locally excited fluorophore quencher pair, a fully reversible interconversion between the RIP, exciplex, and locally excited fluorophore is revealed by spectrally resolved MFE measurements for the long-chain systems (n = 10, 16).The financial support from The Royal Society (RG170378), Ho Chi Minh City University of Technology and Education (T2018-36TD̵) and Austrian Science Fund (FWF-Project P ACS Omega Article DOI: 10.1021/acsomega.8b01232 ACS Omega 2018, 3, 10296−10305 10303 21518-N19) is gratefully acknowledged. D.R.K. is thankful NVIDIA for supporting this research through their GPU Grant Program

Cortical sinus probing, S1P1-dependent entry and flow-based capture of egressing T cells.

The cellular dynamics of the egress of lymphocytes from lymph nodes are poorly defined. Here we visualized the branched organization of lymph node cortical sinuses and found that after entry, some T cells were retained, whereas others returned to the parenchyma. T cells deficient in sphingosine 1-phosphate receptor type 1 probed the sinus surface but failed to enter the sinuses. In some sinuses, T cells became rounded and moved unidirectionally. T cells traveled from cortical sinuses into macrophage-rich sinus areas. Many T cells flowed from medullary sinuses into the subcapsular space. We propose a multistep model of lymph node egress in which cortical sinus probing is followed by entry dependent on sphingosine 1-phosphate receptor type 1, capture of cells in a sinus region with flow, and transport to medullary sinuses and the efferent lymph

Access route selection for percutaneous coronary intervention among Vietnamese patients: Implications for in-hospital costs and outcomes

Background:Little is known about rates of access site (transradial (TRI) or transfemoral (TFI)) preference for percutaneous coronary intervention (PCI) and in-hospital costs of patients undergoing these procedures in lower-and middle-countries. Here, we report on access site use, in-hospital costs and outcomes of patients undergoing PCI in Vietnam.Methods:Information from 868 patients were included in the cohort of 1022 patients recruited into the first PCI registry in Vietnam. The total hospital costs and in-hospital outcomes of patients undergoing TRI and TFI were compared. Hospital costs were obtained from the hospital admission system, and major adverse cardiac events, major bleeding events and length of stay were identified through review of medical records.Findings:TRI was the dominant access site for interventionists (694/868 patients). The TFI group reported more lesions of the left main artery, more previous coronary artery bypass grafts and previous PCI in comparison with the TRI group (all p Interpretations:Among patients undergoing PCI, TRI was associated with lower costs and favourable clinical outcomes relative to TFI

Superconductivity close to magnetic instability in Fe(Se 1-xTex)0.82

We report our study of the evolution of superconductivity and the phase diagram of the ternary Fe(Se1-xTex)0.82 (0≤x≤1.0) system. We discovered a superconducting phase with T c,max=14 K in the 0.3<x<1.0 range. This superconducting phase is suppressed when the sample composition approaches the end member FeTe 0.82, which exhibits an incommensurate antiferromagnetic order. We discuss the relationship between the superconductivity and magnetism of this material system in terms of recent results from neutron-scattering measurements. Our results and analyses suggest that superconductivity in this class of Fe-based compounds is associated with magnetic fluctuations and therefore may be unconventional in nature

Dangerous drug interactions leading to hemolytic uremic syndrome following lung transplantation

<p>Abstract</p> <p>Background</p> <p>To report our experience of a rather uncommon drug interaction, resulting in hemolytic uremic syndrome (HUS).</p> <p>Methods</p> <p>Two consecutive cases of hemolytic uremic syndrome were diagnosed in our service. In both patients the use of macrolides in patients taking Tacrolimus, resulted in high levels of Tacrolimus.</p> <p>Results</p> <p>The first patient was a 48 years old female with Bilateral emphysema. She underwent Single Sequential Lung Transplantation. She developed reperfusion injury requiring prolonged stay. Tacrolimus introduced (Day 51). The patient remained well up till 5 months later; Erythromycin commenced for chest infection. High Tacrolimus levels and a clinical diagnosis of HUS were made. She was treated with plasmapheresis successfully.</p> <p>The second case was a 57 years old female with Emphysema & A1 Antithrypsin deficiency. She underwent Right Single Lung Transplantation. A2 rejection with mild Obliterative Bronchiolitis diagnosed 1 year later and she switched to Tacrolimus. She was admitted to her local Hospital two and a half years later with right middle lobe consolidation. The patient commenced on amoxicillin and clarithromycin. Worsening renal indices, high Tacrolimus levels, hemolytic anemia & low Platelets were detected. HUS diagnosed & treated with plasmapheresis.</p> <p>Conclusions</p> <p>There are 21 cases of HUS following lung transplantation in the literature that may have been induced by high tacrolimus levels. Macrolides in patients taking Cyclosporin or Tacrolimus lead to high levels. Mechanism of action could be glomeruloconstrictor effect with reduced GFR increased production of Endothelin-1 and increased Platelet aggregation.</p

Attitudes and beliefs regarding organ donation among South Asian people in the UK

There is an acute shortage of organ donors in the UK, specifically among South Asian communities. This article reports the findings from the largest ever study undertaken among South Asian people in the UK that seeks to explore attitudes and beliefs towards organ donation. This article highlights that seemingly intractable factors, such as religion and culture, are often tied to more complex issues, such as distrust in the medical system and lack of awareness, that contribute to the shortage of organ donors among South Asian communities in the U

Mixture models for analysis of melting temperature data

<p>Abstract</p> <p>Background</p> <p>In addition to their use in detecting undesired real-time PCR products, melting temperatures are useful for detecting variations in the desired target sequences. Methodological improvements in recent years allow the generation of high-resolution melting-temperature (T_m) data. However, there is currently no convention on how to statistically analyze such high-resolution T_mdata.</p> <p>Results</p> <p>Mixture model analysis was applied to T_mdata. Models were selected based on Akaike's information criterion. Mixture model analysis correctly identified categories in T_mdata obtained for known plasmid targets. Using simulated data, we investigated the number of observations required for model construction. The precision of the reported mixing proportions from data fitted to a preconstructed model was also evaluated.</p> <p>Conclusion</p> <p>Mixture model analysis of T_mdata allows the minimum number of different sequences in a set of amplicons and their relative frequencies to be determined. This approach allows T_mdata to be analyzed, classified, and compared in an unbiased manner.</p

Potential effects of oilseed rape expressing oryzacystatin-1 (OC-1) and of purified insecticidal proteins on larvae of the solitary bee Osmia bicornis

Despite their importance as pollinators in crops and wild plants, solitary bees have not previously been included in non-target testing of insect-resistant transgenic crop plants. Larvae of many solitary bees feed almost exclusively on pollen and thus could be highly exposed to transgene products expressed in the pollen. The potential effects of pollen from oilseed rape expressing the cysteine protease inhibitor oryzacystatin-1 (OC-1) were investigated on larvae of the solitary bee Osmia bicornis (= O. rufa). Furthermore, recombinant OC-1 (rOC-1), the Bt toxin Cry1Ab and the snowdrop lectin Galanthus nivalis agglutinin (GNA) were evaluated for effects on the life history parameters of this important pollinator. Pollen provisions from transgenic OC-1 oilseed rape did not affect overall development. Similarly, high doses of rOC-1 and Cry1Ab as well as a low dose of GNA failed to cause any significant effects. However, a high dose of GNA (0.1%) in the larval diet resulted in significantly increased development time and reduced efficiency in conversion of pollen food into larval body weight. Our results suggest that OC-1 and Cry1Ab expressing transgenic crops would pose a negligible risk for O. bicornis larvae, whereas GNA expressing plants could cause detrimental effects, but only if bees were exposed to high levels of the protein. The described bioassay with bee brood is not only suitable for early tier non-target tests of transgenic plants, but also has broader applicability to other crop protection products