[Severe aplastic anemia exhibiting mild COVID-19 despite high serum IL-6 levels].

COVID-19 is a viral infection characterized by a cytokine storm similar to that in acute respiratory distress syndrome (ARDS). Neutrophils and monocytes are known to play an important role in tissue damage in ARDS. COVID-19 has been reported to be more severe in patients with hematological malignancies; however, there are few reports of COVID-19 in patients with aplastic anemia. Moreover, how aplastic anemia affects COVID-19 remains unclear. Here, we report the case of a COVID-19 patient with aplastic anemia who had high serum IL-6 levels but did not progress to the severe form of COVID-19. We inferred that severe neutropenia and monocytopenia due to aplastic anemia could contribute to a mild form of COVID-19, although a risk of more severe secondary bacterial infections exists.

Clonal Cytopenia of Undetermined Significance in a Patient with Congenital Wilms' Tumor 1 and Acquired DNMT3A Gene Mutations.

Congenital mutations of the Wilms' tumor 1 (WT1) gene can lead to various abnormalities, including renal/gonadal developmental disorders and cardiac malformations. Although there have been many reports of somatic WT1 mutations in patients with acute myeloid leukemia and myelodysplastic syndrome, congenital WT1 mutations have not been reported in hematological disorders. We herein report a patient with early-onset clonal cytopenia of undetermined significance that was associated with a congenital mutation of WT1 and an acquired mutation of DNMT3A [encoding DNA (cytosine-5)-methyltransferase 3A].

Detailed kinetic model for hexyl sulfide pyrolysis and its desulfurization by supercritical water.

A detailed reaction network is proposed for the pyrolysis and desulfurization of hexyl sulfide in the presence or absence of both supercritical water (SCW) and hexadecane, but without any added H2 or catalyst, for T = 400-450 °C. The new kinetic model is developed using the Reaction Mechanism Generator (RMG) software where most of the rate coefficients are derived from quantum chemical calculations. We previously reported that pentane, carbon monoxide and carbon dioxide are major products of hexyl sulfide desulfurization in SCW, but not in the anhydrous pyrolysis of hexyl sulfide. The observation of CO and CO2 in the reaction products indicates that water effectively acts as a hydrogen source; presumably this assists in sulfur reduction to H2S. Kinetic parameters for several of the important reactions are calculated using transition state theory and quantum chemical calculations at the CBS-QB3 level of theory and then further refined using CCSD(T)-F12//cc-pVTZ-F12 single point energies. Predictions from the new kinetic model agree with factor-of-2 accuracy with new and previously published experimental data for hexyl sulfide conversion and for yields of most major products, either neat or in a hexadecane solvent, both in the presence and absence of SCW. Flux analysis was then used to identify the most important reaction steps, and sensitivity analysis was used to propose reactions that should be studied further in the future to decrease the model's uncertainty. This study establishes the molecular role of water as diluent, hydrogen bond donor, and reductant in the decomposition of hexyl sulfide. Future work to add molecular weight growth pathways to the model would lead to a more complete mechanism, resulting in improved predictions of product yields.

Combining experiment and theory to elucidate the role of supercritical water in sulfide decomposition.

The cleavage of C-S linkages plays a key role in fuel processing and organic geochemistry. Water is known to affect these processes, and several hypotheses have been proposed, but the mechanism has been elusive. Here we use both experiment and theory to demonstrate that supercritical water reacts with intermediates formed during alkyl sulfide decomposition. During hexyl sulfide decomposition in supercritical water, pentane and CO + CO2 were detected in addition to the expected six carbon products. A multi-step reaction sequence for hexyl sulfide reacting with supercritical water is proposed which explains the surprising products, and quantum chemical calculations provide quantitative rates that support the proposed mechanism. The key sequence is cleavage of one C-S bond to form a thioaldehyde via radical reactions, followed by a pericyclic addition of water to the C[double bond, length as m-dash]S bond to form a geminal mercaptoalcohol. The mercaptoalcohol decomposes into an aldehyde and H2S either directly or via a water-catalyzed 6-membered ring transition state. The aldehyde quickly decomposes into CO plus pentane by radical reactions. The time is ripe for quantitative modelling of organosulfur reaction kinetics based on modern quantum chemistry.