The Dissociation of Vibrationally Excited CH3OSO Radicals and Their Photolytic Precurson, Methoxysulfinyl Chloride

I developed a synthesis of an unstable molecule that undergoes cleavage when exposed to light. Laurie Butler, in her lab at the University of Chicago, studied the rate of decay/bond dissociation for this molecule. It serves as a model for bond dissociation processes that occur with pollutant molecules in the upper atmosphere. --author-supplied descriptio

Mice with genetic deletion of group VIA phospholipase A2β exhibit impaired macrophage function and increased parasite load in Trypanosoma cruzi-induced myocarditis

Trypanosoma cruzi infection, which is the etiological agent of Chagas disease, is associated with intense inflammation during the acute and chronic phases. The pathological progression of Chagas disease is influenced by the infiltration and transmigration of inflammatory cells across the endothelium to infected tissues, which are carefully regulated processes involving several molecular mediators, including adhesion molecules and platelet-activating factor (PAF). We have shown that PAF production is dependent upon calcium-independent group VIA phospholipase A(2)β (iPLA(2)β) following infection of human coronary artery endothelial cells (HCAECs) with T. cruzi, suggesting that the absence of iPLA(2)β may decrease the recruitment of inflammatory cells to the heart to manage parasite accumulation. Cardiac endothelial cells isolated from iPLA(2)β-knockout (iPLA(2)β-KO) mice infected with T. cruzi demonstrated decreased PAF production compared to that by cells isolated from wild-type (WT) mice but demonstrated increases in adhesion molecule expression similar to those seen in WT mice. Myocardial inflammation in iPLA(2)β-KO mice infected with T. cruzi was similar in severity to that in WT mice, but the iPLA(2)β-KO mouse myocardium contained more parasite pseudocysts. Upon activation, macrophages from iPLA(2)β-KO mice produced significantly less nitric oxide (NO) and caused less T. cruzi inhibition than macrophages from wild-type mice. Thus, the absence of iPLA(2)β activity does not influence myocardial inflammation, but iPLA(2)β is essential for T. cruzi clearance

Multiorbital exciton formation in an organic semiconductor

Harnessing the optoelectronic response of organic semiconductors requires a thorough understanding of the fundamental light-matter interaction that is dominated by the excitation of correlated electron-hole pairs, i.e. excitons. The nature of these excitons would be fully captured by knowing the quantum-mechanical wavefunction, which, however, is difficult to access both theoretically and experimentally. Here, we use femtosecond photoemission orbital tomography in combination with many-body perturbation theory to gain access to exciton wavefunctions in organic semiconductors. We find that the coherent sum of multiple electron-hole pair contributions that typically make up a single exciton can be experimentally evidenced by photoelectron spectroscopy. For the prototypical organic semiconductor buckminsterfullerene (C$_{60}$), we show how to disentangle such multiorbital contributions and thereby access key properties of the exciton wavefunctions including localization, charge-transfer character, and ultrafast exciton formation and relaxation dynamics

Ab-initio structural, elastic, and vibrational properties of carbon nanotubes

A study based on ab initio calculations is presented on the estructural, elastic, and vibrational properties of single-wall carbon nanotubes with different radii and chiralities. We use SIESTA, an implementation of pseudopotential-density-functional theory which allows calculations on systems with a large number of atoms per cell. Different quantities like bond distances, Young moduli, Poisson ratio and the frequencies of different phonon branches are monitored versus tube radius. The validity of expectations based on graphite is explored down to small radii, where some deviations appear related to the curvature effects. For the phonon spectra, the results are compared with the predictions of the simple zone-folding approximation. Except for the known defficiencies of this approximation in the low-frequency vibrational regions, it offers quite accurate results, even for relatively small radii.Comment: 13 pages, 7 figures, submitted to Phys. Rev. B (11 Nov. 98

Pathways of patients with chronic haematological malignancies:a report from the UK’s population-based HMRN

Background Arising in blood and lymph-forming tissues, haematological malignancies (leukaemias, lymphomas and myelomas) are the fifth most common group of cancers. Around 60% are currently incurable and follow a chronic, remitting–relapsing pathway often initially managed by ‘watch & wait’. This involves hospital-based monitoring, followed by treatment if the cancer progresses (which not all do) and then further observation, in a process that may continually repeat. New treatments are constantly emerging, survival is improving and prevalence is rising, but population-based data documenting entire care pathway are sparse. Hence, empirically-based incidence and prevalence estimates about various treatment states (watch and wait, first-line treatment, observation, second-line treatment, etc.) and patterns of healthcare activity are lacking. Likewise, despite complex trajectories, anxiety-provoking watch and wait, and therapies that impede quality of life and incur marked healthcare costs, evidence about patient preferences for information sharing and treatment decisions is scant. Objectives Primary – to generate high-quality, evidence-based information about the care pathways of the general population of patients with chronic haematological malignancies. Secondary – to produce information resources suitable for testing in routine National Health Service practice. Design Population-based cohort of ≈ 8000 patients with chronic haematological malignancies, incorporating five nested work packages, each with its own individual design: (1) exploration of patient experiences: information and treatment decisions; (2) population-based analyses; (3) health economics; (4) development of information resources to support decision-making; and (5) patient well-being and decision-making survey. Setting This programme is predicated on the infrastructure of the United Kingdom’s Haematological Malignancy Research Network (www.hmrn.org); which provides ‘real-world’, robust, generalisable data to inform research and clinical practice, nationally and internationally. Set in Yorkshire and Humberside, the Haematological Malignancy Research Network’s catchment population of ≈ 4 million has a comparable sex, age, urban/rural, and area-based deprivation (Index of Multiple Deprivation, income domain) distribution to the United Kingdom as a whole; and in terms of ethnic diversity the region is centrally ranked, with around 80% of residents identifying as White British, 9% as Asian and 2% as black. Within the Haematological Malignancy Research Network, clinical practice adheres to national guidelines, and all patients with blood cancers are centrally diagnosed (≈ 2500 each year), tracked through their treatment pathways and linked to national databases (deaths, cancer registrations and Hospital Episode Statistics). Linked to the same national databases, the Haematological Malignancy Research Network also contains an age- and sex-matched general-population cohort. Participants Patients aged ≥ 18 years, resident in the study region, and diagnosed with chronic lymphocytic leukaemia, follicular lymphoma or myeloma. Methods Core Haematological Malignancy Research Network data were used to compare the hospital activity of patients with chronic lymphocytic leukaemia, follicular lymphoma and myeloma with that of the general population. Following additional linkages to genetic and clinical data, follicular lymphoma prognostic factors were examined. Two self-administered questionnaires addressing (1) quality of life and well-being and (2) decision-making were iteratively developed, piloted and deployed. Linkage to quality of life, clinical information and Hospital Episode Statistics enabled economic (myeloma) model development. In-depth interviews were conducted with 35 patients (10 alongside relatives). Results Trajectories of ≈ 8000 patients were mapped, and patient-pathway visualisations summarising individual and aggregate information were developed. As expected, patients with chronic blood cancers experienced higher levels of hospital activity than their general population counterparts, the largest effects being for myeloma. Following survey deployment, 3153 patients were recruited across 14 hospitals, 1282 with chronic lymphocytic leukaemia, follicular lymphoma or myeloma. Over half of the questionnaires were completed by patients on watch and wait; the remainder were completed during treatment or post-chemotherapy monitoring. Information gathered, coupled with in-depth interviews, demonstrated patients’ marked anxiety and fluctuating preferences for information sharing and decision-making, contingent on complex, inter-related factors. In turn, prognostic and microsimulation economic models were used to predict individual-level trajectories across multiple treatment lines, examining associated overall survival, costs and quality-adjusted life-years. Limitations Survey mapping to individual care pathways could not be completed because the COVID-19 pandemic delayed clinical data collection. Patients who attended clinics and participated in the survey were more likely than non-attenders to have had first-line chemotherapy, be slightly younger and live in more affluent areas. Conclusions This programme collated high-quality, population-based evidence. Previously lacking, this, coupled with new findings on preferences for information sharing and treatment decisions, provides the foundation for future research. Future work The translation of information accrued into resources suitable for testing in routine NHS practice is key. In this regard, COVID-19 has changed the communication landscape. The visualisations developed by this programme require further refinement/testing using participatory co-design with stakeholder groups. Underpinned by a suitable protocol applied within a single multidisciplinary team setting, prior to further evaluation within/outside the region, such outputs require testing in a cluster-randomised trial. Funding This award was funded by the National Institute for Health and Care Research (NIHR) Programme Grants for Applied Research programme (NIHR award ref: RP-PG-0613-20002) and is published in full in Programme Grants for Applied Research; Vol. 12, No. 5. See the NIHR Funding and Awards website for further award information

Effect of First-Line Chemotherapy Combined With Cetuximab or Bevacizumab on Overall Survival in Patients With KRAS Wild-Type Advanced or Metastatic Colorectal Cancer: A Randomized Clinical Trial

Combining biologic monoclonal antibodies with chemotherapeutic cytotoxic drugs provides clinical benefit to patients with advanced or metastatic colorectal cancer, but the optimal choice of the initial biologic therapy in previously untreated patients is unknown

Th17 cells are more protective than Th1 cells against the intracellular parasite Trypanosoma cruzi

Th17 cells are a subset of CD4+ T cells known to play a central role in the pathogenesis of many autoimmune diseases, as well as in the defense against some extracellular bacteria and fungi. However, Th17 cells are not believed to have a significant function against intracellular infections. In contrast to this paradigm, we have discovered that Th17 cells provide robust protection against Trypanosoma cruzi, the intracellular protozoan parasite that causes Chagas disease. Th17 cells confer significantly stronger protection against T. cruzi-related mortality than even Th1 cells, traditionally thought to be the CD4+ T cell subset most important for immunity to T. cruzi and other intracellular microorganisms. Mechanistically, Th17 cells can directly protect infected cells through the IL-17A-dependent induction of NADPH oxidase, involved in the phagocyte respiratory burst response, and provide indirect help through IL-21-dependent activation of CD8+ T cells. The discovery of these novel Th17 cell-mediated direct protective and indirect helper effects important for intracellular immunity highlights the diversity of Th17 cell roles, and increases understanding of protective T. cruzi immunity, aiding the development of therapeutics and vaccines for Chagas disease

ACC/AHA/ASNC Guidelines for the Clinical Use of Cardiac Radionuclide Imaging—Executive Summary: A Report of the American College of Cardiology/American HeartAssociation Task Force on Practice Guidelines (ACC/AHA/ASNC Committee to Revise the 1995 Guidelines for the Clinical Use of Cardiac Radionuclide Imaging)

The American College of Cardiology (ACC)/American Heart Association (AHA) Task Force on Practice Guidelines regularly reviews existing guidelines to determine when an update or full revision is needed. Guidelines for the Clinical Use of Cardiac Radionuclide Imaging were originally published in 1986 and updated in 1995. Important new developments have continued to occur since 1995, particularly in the areas of acute and chronic ischemic syndromes and heart failure. The Task Force therefore believed the topic should be revisited de novo and invited the American Society for Nuclear Cardiology (ASNC) to cosponsor the undertaking, which represents a joint effort of the 3 organizations