Publications by authors named "LARSON V"

The activation of dioxygen at haem and non-haem metal centres, and subsequent functionalization of unactivated C‒H bonds, has been a focal point of much research. In iron-mediated oxidation reactions, O binding at an iron(II) centre is often accompanied by an oxidation of the iron centre. Here we demonstrate dioxygen activation by sodium tetraphenylborate and protons in the presence of an iron(II) complex to form a reactive radical species, whereby the iron oxidation state remains unaltered in the presence of a highly oxidizing phenoxyl radical and O.

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We report the macrocyclic ring size-electronic structure-electrophilic reactivity correlation of mononuclear nonheme iron(III)-peroxo complexes bearing -tetramethylated cyclam analogues (-TMC), [Fe(O)(12-TMC)] (), [Fe(O)(13-TMC)] (), and [Fe(O)(14-TMC)] (), as a model study of Rieske oxygenases. The Fe(III)-peroxo complexes show the same δ and pseudo-σ bonds between iron and the peroxo ligand. However, the strength of these interactions varies depending on the ring size of the -TMC ligands; the overall Fe-O bond strength and the strength of the Fe-O δ bond increase gradually as the ring size of the -TMC ligands becomes smaller, such as from 14-TMC to 13-TMC to 12-TMC.

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Sustainable manure management technologies are needed, and combining anaerobic digestion (AD) for energy generation and aerobic composting (AC) to stabilize digestate and remove emerging contaminants (ECs), including veterinary pharmaceuticals and steroid hormones, is promising. This study identified post-AD, AC operating conditions that maximized degradation of study ECs, expected to be present in cattle manure digested using treated municipal wastewater as the water source. Study ECs included sulfamethoxazole (SMX), chlortetracycline (CTC), oxytetracycline (OTC), estrone (E1), and naproxen (NPX).

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High-valent first-row transition-metal-oxo complexes are important intermediates in biologically and chemically relevant oxidative transformations of organic molecules and in the water splitting reaction in (artificial) photosynthesis. While high-valent Fe- and Mn-oxo complexes have been characterized in detail, much less is known about their analogues with late transition metals. In this study, we present the synthesis and detailed characterization of a unique mononuclear terminal Ni-O complex.

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In this paper, we report the preparation, spectroscopic and theoretical characterization, and reactivity studies of a Co(IV)-oxo complex bearing an N4-macrocyclic coligand, 12-TBC (12-TBC = 1,4,7,10-tetrabenzyl-1,4,7,10-tetraazacyclododecane). On the basis of the ligand and the structure of the Co(II) precursor, [Co(12-TBC)(CFSO)], one would assume that this species corresponds to a tetragonal Co(IV)-oxo complex, but the spectroscopic data do not support this notion. Co K-edge XAS data show that the treatment of the Co(II) precursor with iodosylbenzene (PhIO) as an oxidant at -40 °C in the presence of a proton source leads to a distinct shift in the Co K-edge, in agreement with the formation of a Co(IV) intermediate.

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A 10-year-old, intact male Siberian husky dog was presented for a suspected left renal cyst. Computed tomography (CT) identified a large, left kidney mass with retroperitoneal hemorrhage. A left-sided nephrectomy was performed, and histopathology confirmed a renal plasmacytoma.

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Background: As more people become vaccinated against the SARS-CoV-2 virus, reports of delayed cutaneous hypersensitivity reactions are beginning to emerge.

Methods: In this IRB-approved retrospective case series, biopsy specimens of potential cutaneous adverse reactions from the Pfizer-BioNTech or Moderna mRNA vaccine were identified and reviewed. Clinical information was obtained through the requisition form, referring clinician, or medical chart review.

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High-valent metal-oxo species with multiply-bonded M-O groups have been proposed as key intermediates in many biological and abiological catalytic oxidation reactions. These intermediates are implicated as active oxidants in alkane hydroxylation, olefin epoxidation and other oxidation reactions. For example, [FeO(porphyrinato)] cofactors bearing π-radical porphyrinato ligands oxidize organic substrates in cytochrome P450 enzymes, which are common to many life forms.

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CD19 CAR T-cell therapy with axicabtagene ciloleucel (axi-cel) for relapsed or refractory (R/R) large B cell lymphoma (LBCL) may lead to durable remissions, however, prolonged cytopenias and infections may occur. In this single center retrospective study of 85 patients, we characterized immune reconstitution and infections for patients remaining in remission after axi-cel for LBCL. Prolonged cytopenias (those occurring at or after day 30 following infusion) were common with >= grade 3 neutropenia seen in 21/70 (30-0%) patients at day 30 and persisting in 3/31 (9-7%) patients at 1 year.

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The efficacy and toxicity of lomustine and prednisone for treating high-grade completely excised mast cell tumors (MCTs) was evaluated in a retrospective study of 15 dogs. Dogs were treated with lomustine (CCNU) at 70 mg/m every 4 weeks and prednisone at 0.5 to 1 mg/kg body weight PO daily.

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: Pruritus is a well-recognized paraneoplastic phenomenon. Previous studies have examined the association of itch with a variety of malignancies in adults. However, no large study has examined this association in a pediatric population.

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Objective: Posttraumatic stress disorder (PTSD) is a highly prevalent psychiatric disorder associated with disruption in social and occupational function. Transcranial magnetic stimulation (TMS) represents a novel approach to PTSD, and intermittent theta-burst stimulation (iTBS) is a new, more rapid administration protocol with data supporting efficacy in depression. The authors conducted a sham-controlled study of iTBS for PTSD.

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The purpose of this trial was to test whether right prefrontal cortex 1 Hz versus 10 Hz rTMS provides a significantly greater improvement in PTSD symptoms and/or function. Veterans 18 to 50 years of age suffering from PTSD were randomized to right prefrontal 1 Hz rTMS [2400 pulses/session] versus right prefrontal 10 Hz rTMS [2400 pulses/session]. The treatments were performed 5 days a week for 6 weeks with a 3-week taper using the NeuroStar system.

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Background: Facilitating neural activity using non-invasive brain stimulation may improve extinction-based treatments for posttraumatic stress disorder (PTSD).

Objective/hypothesis: Here, we examined the feasibility of simultaneous transcranial direct current stimulation (tDCS) application during virtual reality (VR) to reduce psychophysiological arousal and symptoms in Veterans with PTSD.

Methods: Twelve Veterans with PTSD received six combat-related VR exposure sessions during sham-controlled tDCS targeting ventromedial prefrontal cortex.

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Background: Pruritus has been associated with cancer. However, limited data are available on the types of underlying malignancies associated with pruritus.

Objective: We sought to characterize the association between pruritus and different cancer types, as well as variations by racial group.

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The inwardly rectifying K channel K4.1 is broadly expressed by CNS glia and deficits in K4.1 lead to seizures and myelin vacuolization.

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We report a consanguineous family with three affected siblings with novel mutation in the KCNJ10 gene. All three presented with central nervous system symptoms in the form of infantile focal seizures, ataxia, slurred speech with early developmental delay and intellectual disability in two siblings. None had any associated electrolyte abnormalities and no symptomatic hearing deficits were observed.

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NG2(+) glial cells are a dynamic population of non-neuronal cells that give rise to myelinating oligodendrocytes in the central nervous system. These cells express numerous ion channels and neurotransmitter receptors, which endow them with a complex electrophysiological profile that is unique among glial cells. Despite extensive analysis of the electrophysiological properties of these cells, relatively little was known about the molecular identity of the channels and receptors that they express.

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While pancreatitis is now recognized as a common ailment in cats, the diagnosis remains challenging due to discordant results and suboptimal sensitivity of ultrasound and specific feline pancreatic lipase (Spec fPL) assay. Pancreatitis also shares similar clinical features with pancreatic carcinoma, a rare but aggressive disease with a grave prognosis. The objective of this pilot study was to compare the plasma proteomes of normal healthy cats (n = 6), cats with pancreatitis (n = 6), and cats with pancreatic carcinoma (n = 6) in order to identify potential new biomarkers of feline pancreatic disease.

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Background: Canine high-grade multicentric lymphoma, a common disease with variable response to chemotherapy, is often diagnosed using cytology.

Objectives: The purpose of the study was to compare cytologic features of canine peripheral lymph node aspirates collected at diagnosis and at relapse, and evaluate their usefulness in predicting survival.

Methods: Cytologic scoring based on a rubric and nuclear morphometry analyses were performed on cytologic smears collected at diagnosis and at relapse.

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A 7-year-old Doberman pinscher dog was referred for evaluation of a radio-opaque thoracic mass. The left cranial lung lobe and associated mass were surgically resected and histopathology confirmed the presence of an extramedullary plasmacytoma (EMP). This is the first clinical description of an EMP in the lung of a veterinary patient.

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Eukaryotic translation initiation factor (eIF)4B stimulates recruitment of mRNA to the 43S ribosomal pre-initiation complex (PIC). Yeast eIF4B (yeIF4B), shown previously to bind single-stranded (ss) RNA, consists of an N-terminal domain (NTD), predicted to be unstructured in solution; an RNA-recognition motif (RRM); an unusual domain comprised of seven imperfect repeats of 26 amino acids; and a C-terminal domain. Although the mechanism of yeIF4B action has remained obscure, most models have suggested central roles for its RRM and ssRNA-binding activity.

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