Coherent mixing of singlet and triplet states in acrolein and ketene: a computational strategy for simulating the electron-nuclear dynamics of intersystem crossing.

We present a theoretical study of intersystem crossing (ISC) in acrolein and ketene with the Ehrenfest method that can describe a superposition of singlet and triplet states. Our simulations illustrate a new mechanistic effect of ISC, namely, that a superposition of singlets and triplets yields nonadiabatic dynamics characteristic of that superposition rather than the constituent state potential energy surfaces. This effect is particularly significant in ketene, where mixing of singlet and triplet states along the approach to a singlet/singlet conical intersection occurs, with the spin-orbit coupling (SOC) remaining small throughout. In both cases, the effects require many recrossings of the singlet/triplet state crossing seam, consistent with the textbook treatment of ISC

Correction of both immunodeficiency and hypoparathyroidism by thymus transplantation in complete DiGeorge Syndrome

Combined immune deficiency due to athymia in patients with complete DiGeorge syndrome can be corrected by allogeneic thymus transplantation. Hypoparathyroidism is a frequent concomitant clinical problem in these patients, which persists after thymus transplantation. Cotransplantation of allogeneic thymus and parental parathyroid tissue has been attempted but does not achieve durable correction of the patients' hypoparathyroidism due to parathyroid graft rejection. Surprisingly, we observed correction of hypoparathyroidism in one patient after thymus transplantation. Immunohistochemical analysis and fluorescence in situ hybridization confirmed the presence of allogeneic parathyroid tissue in the patient's thymus transplant biopsy. Despite a lack of HLA‐matching between thymus donor and recipient, the reconstituted immune system displays tolerance toward the thymus donor. Therefore we expect this patient's hypoparathyroidism to be permanently cured. It is recognised that ectopic parathyroid tissue is not infrequently found in the thymus. If such thymuses could be identified, we propose that their use would offer a compelling approach to achieving lasting correction of both immunodeficiency and hypoparathyroidism

Epstein-Barr virus (EBV) deletions as biomarkers of response to treatment of chronic active EBV

Chronic active Epstein–Barr virus (CAEBV) disease is a rare condition characterised by persistent EBV infection in previously healthy individuals. Defective EBV genomes were found in East Asian patients with CAEBV. In the present study, we sequenced 14 blood EBV samples from three UK patients with CAEBV, comparing the results with saliva CAEBV samples and other conditions. We observed EBV deletions in blood, some of which may disrupt viral replication, but not saliva in CAEBV. Deletions were lost overtime after successful treatment. These findings are compatible with CAEBV being associated with the evolution and persistence of EBV+ haematological clones that are lost on successful treatment

Chemical Safety Assessment Using Read-Across: Assessing the Use of Novel Testing Methods to Strengthen the Evidence Base for Decision Making

Background: Safety assessment for repeated dose toxicity is one of the largest challenges in the process to replace animal testing. This is also one of the proof of concept ambitions of SEURAT-1, the largest ever European Union research initiative on alternative testing, co-funded by the European Commission and Cosmetics Europe. This review is based on the discussion and outcome of a workshop organized on initiative of the SEURAT-1 consortium joined by a group of international experts with complementary knowledge to further develop traditional read-across and include new approach data. Objectives: The aim of the suggested strategy for chemical read-across is to show how a traditional read-across based on structural similarities between source and target substance can be strengthened with additional evidence from new approach data—for example, information from in vitro molecular screening, “-omics” assays and computational models—to reach regulatory acceptance. Methods: We identified four read-across scenarios that cover typical human health assessment situations. For each such decision context, we suggested several chemical groups as examples to prove when read-across between group members is possible, considering both chemical and biological similarities. Conclusions: We agreed to carry out the complete read-across exercise for at least one chemical category per read-across scenario in the context of SEURAT-1, and the results of this exercise will be completed and presented by the end of the research initiative in December 2015

New insights into risk factors for transplant-associated thrombotic microangiopathy in pediatric HSCT

This study aimed to identify a risk profile for development of transplant-associated thrombotic microangiopathy (TA-TMA) in children undergoing hematopoietic stem cell transplantation (HSCT). Between 2013 and 2016, 439 children underwent 474 HSCTs at 2 supraregional United Kingdom centers. At a median of 153 days post-HSCT, TA-TMA occurred among 25 of 441 evaluable cases (5.6%) with no evidence of center variation. Sex, underlying disease, intensity of the conditioning, total body irradiation–based conditioning, the use of calcineurin inhibitors, venoocclusive disease, and viral reactivation did not influence the development of TA-TMA. Donor type: matched sibling donor/matched family donor vs matched unrelated donor vs mismatched unrelated donor/haplo-HSCT, showed a trend toward the development of TA-TMA in 1.8% vs 6.1% vs 8.3%, respectively. Presence of active comorbidity was associated with an increased risk for TA-TMA; 13% vs 3.7% in the absence of comorbidity. The risk of TA-TMA was threefold higher among patients who received >1 transplant. TA-TMA rates were significantly higher among patients with acute graft-versus-host disease (aGVHD) grades III to IV vs aGVHD grade 0 to II. On multivariate analysis, the presence of active comorbidity, >1 transplant, aGVHD grade III to IV were risk factors for TA-TMA (odds ratio [OR]: 5.1, 5.2, and 26.9; respectively), whereas the use of cyclosporine A/tacrolimus-based GVHD prophylaxis was not a risk factor for TA-TMA (OR: 0.3). Active comorbidity, subsequent transplant, and aGVHD grades III to IV were significant risk factors for TA-TMA. TA-TMA might represent a form of a vascular GVHD, and therefore, continuing control of aGVHD is important to prevent worsening of TA-TMA associated with GVHD

Key components of anaphylaxis management plans: consensus findings from a national electronic Delphi study

OBJECTIVES: There is no international consensus on the components of anaphylaxis management plans and responsibility for their design and delivery is contested. We set out to establish consensus among relevant specialist and generalist clinicians on this issue to inform future randomized controlled trials. DESIGN: A two-round electronic Delphi study completed by a 25-person, multidisciplinary expert panel. Participants scored the importance of a range of statements on anaphylaxis management, identified from a systematic review of the literature, on a five-point scale ranging from 'very important' to 'irrelevant'. Consensus was defined a priori as being achieved if 80% or more of panel members rated a statement as 'important' or 'very important' after Round 2. SETTING: Primary and secondary care and academic settings in the UK and Ireland. PARTICIPANTS: Twenty-five medical, nursing and allied health professionals. MAIN OUTCOME MEASURES: Consensus on the key components of anaphylaxis management plans. RESULTS: The response rate was 84% (n = 21) for Round 1 and 96% (n = 24) for Round 2. The key components of emergency care on which consensus was achieved included: awareness of trigger factors (100%); recognition and emergency management of reactions of different severity (100%); and clear information on adrenaline (epinephrine) use (100%). Consensus on longer-term management issues included: clear written guidelines on anaphylaxis management (96%); annual review of plans (87%); and plans that were tailored to individual needs (82%). CONCLUSIONS: This national consensus-building exercise generated widespread agreement that emergency plans need to be simple, clear and generic, making them easy to implement in a crisis. In contrast, long-term plans need to be negotiated between patient/carers and professionals, and tailored to individual needs. The effectiveness of this expert-agreed long-term plan now needs to be evaluated rigorously

Rationale, design and population baseline characteristics of the PERFORM Vascular Project: an ancillary study of the Prevention of cerebrovascular and cardiovascular Events of ischemic origin with teRutroban in patients with a history oF ischemic strOke or tRansient ischeMic attack (PERFORM) trial

<p><b>Purpose</b></p> <p>PERFORM is exploring the efficacy of terutroban versus aspirin for secondary prevention in patients with a history of ischemic stroke or transient ischemic attacks (TIAs). The PERFORM Vascular Project will evaluate the effect of terutroban on progression of atherosclerosis, as assessed by change in carotid intima-media thickness (CIMT) in a subgroup of patients.</p> <p><b>Methods and results</b></p> <p>The Vascular Project includes structural (CIMT, carotid plaques) and functional (carotid stiffness) vascular studies in all patients showing at least one carotid plaque at entry. Expected mean follow-up is 36 months. Primary endpoint is rate of change of CIMT. Secondary endpoints include emergent plaques and assessment of carotid stiffness. 1,100 patients are required for 90% statistical power to detect treatment-related CIMT difference of 0.025 mm. The first patient was randomized in April 2006.</p> <p><b>Conclusions</b></p> <p>The PERFORM Vascular Project will investigate terutroban’s effect on vascular structure and function in patients with a history of ischemic stroke or TIAs.</p&gt

Comparison of performance-based measures among native Japanese, Japanese-Americans in Hawaii and Caucasian women in the United States, ages 65 years and over: a cross-sectional study

BACKGROUND: Japanese (both in Japan and Hawaii) have a lower incidence of falls and of hip fracture than North American and European Caucasians, but the reasons for these differences are not clear. SUBJECTS AND METHODS: A cross-sectional study. We compared neuromuscular risk factors for falls using performance-based measures (chair stand time, usual and rapid walking speed, and grip strength) among 163 Japanese women in Japan, 681 Japanese-American women in Hawaii and 9403 Caucasian women in the United States aged 65 years and over. RESULTS: After adjusting for age, the Caucasian women required about 40% more time to complete 5 chair stands than either group of Japanese. Walking speed was about 10% slower among Caucasians than native Japanese, whereas Japanese-American women in Hawaii walked about 11% faster than native Japanese. Grip strength was greatest in Japan, which may reflect the rural farming district that this sample was drawn from. Additional adjustment for height, weight or body mass index increased the adjusted means of chair stand time and grip strength among Japanese, but the differences remained significant. CONCLUSIONS: Both native Japanese and Japanese-American women in Hawaii performed better than Caucasians on chair stand time and walking speed tests, and native Japanese had greater grip strength than Japanese in Hawaii and Caucasians. The biological implications of these differences in performance are uncertain, but may be useful in planning future comparisons between populations

Model of the complex of Parathyroid hormone-2 receptor and Tuberoinfundibular peptide of 39 residues

<p>Abstract</p> <p>Background</p> <p>We aim to propose interactions between the parathyroid hormone-2 receptor (PTH2R) and its ligand the tuberoinfundibular peptide of 39 residues (TIP39) by constructing a homology model of their complex. The two related peptides parathyroid hormone (PTH) and parathyroid hormone related protein (PTHrP) are compared with the complex to examine their interactions.</p> <p>Findings</p> <p>In the model, the hydrophobic N-terminus of TIP39 is buried in a hydrophobic part of the central cavity between helices 3 and 7. Comparison of the peptide sequences indicates that the main discriminator between the agonistic peptides TIP39 and PTH and the inactive PTHrP is a tryptophan-phenylalanine replacement. The model indicates that the smaller phenylalanine in PTHrP does not completely occupy the binding site of the larger tryptophan residue in the other peptides. As only TIP39 causes internalisation of the receptor and the primary difference being an aspartic acid in position 7 of TIP39 that interacts with histidine 396 in the receptor, versus isoleucine/histidine residues in the related hormones, this might be a trigger interaction for the events that cause internalisation.</p> <p>Conclusions</p> <p>A model is constructed for the complex and a trigger interaction for full agonistic activation between aspartic acid 7 of TIP39 and histidine 396 in the receptor is proposed.</p