Multiple Hepatic Lesions During Acute Leukemia Remissions

The US and CT manifestations of multiple small hepatic lesions of 15 patients during their remissions following chemotherapy for acute leukemia were reviewed. Liver biopsies established the diagnoses in 5 of the 15 patients. Despite their remissions, two cases had leukemic involvement. Others had microabscesses, 2 due to candida and 1 due to peptostreptococcus. Ultrasonographically, the microabscesses and leukemic involvement in the liver consisted of multiple round hypoechoic and target-like masses. With CT, these appeared as multiple zones of diminished attenuation. Only distal acoustic enhancement with US could differentiate these disease processes

Heme-dependent autophosphorylation of a heme sensor kinase, ChrS, from Corynebacterium diphtheriae reconstituted in proteoliposomes

AbstractCorynebacterium diphteriae employs the response regulator, ChrA, and the sensor kinase, ChrS, of a two-component signal transduction system to utilize host heme iron. Although ChrS is predicted to encode a heme sensor, the sensing mechanism remains to be characterized. In this report, ChrS expressed in Eshcherichia coli membranes was solubilized and purified using decylmaltoside. ChrS protein incorporated into proteoliposomes catalyzed heme-dependent autophosphorylation by ATP. Other metalloporphyrins and iron did not stimulate kinase activity. The UV–Vis spectrum of hemin in the ChrS–proteoliposomes indicated that heme directly interacts with ChrS. This is the first functional reconstitution of a bacterial heme-sensing protein

Quantitative Analysis and Manipulation of Alkali Metal Cations at the Cathode Surface in Membrane Electrode Assembly Electrolyzers for CO₂ Reduction Reactions

Kato S., Ito S., Nakahata S., et al. Quantitative Analysis and Manipulation of Alkali Metal Cations at the Cathode Surface in Membrane Electrode Assembly Electrolyzers for CO₂ Reduction Reactions. ChemSusChem, (2024); https://doi.org/10.1002/cssc.202401013.The stable operation of the CO₂ reduction reaction (CO₂RR) in membrane electrode assembly (MEA) electrolyzers is known to be hindered by the accumulation of bicarbonate salt, which are derived from alkali metal cations in anolytes, on the cathode side. In this study, we conducted a quantitative evaluation of the correlation between the CO₂RR activity and the transported alkali metal cations in MEA electrolyzers. As a result, although the presence of transported alkali metal cations on the cathode surface significantly contributes to the generation of C₂₊ compounds, the rate of K⁺ ion transport did not match the selectivity of C₂₊, suggesting that a continuous supply of high amount of K⁺ to the cathode surface is not required for C₂₊ formation. Based on these findings, we achieved a faradaic efficiency (FE) and a partial current density for C₂₊ of 77 % and 230 mA cm⁻², respectively, even after switching the anode solution from 0.1 M KHCO₃ to a dilute K⁺ solution (<7 mM). These values were almost identical to those when 0.1 M KHCO₃ was continuously supplied. Based on this insight, we successfully improved the durability of the system against salt precipitation by intermittently supplying concentrated KHCO₃, compared with the continuous supply

Enhanced expression of nicotinamide nucleotide transhydrogenase (NNT) and its role in a human T cell line continuously exposed to asbestos

The effects of asbestos fibers on human immune cells have not been well documented. We have developed a continuously exposed cell line model using the human T-lymphotropic virus 1 (HTLV-1)-immortalized human T cell line MT-2. Sublines continuously exposed to chrysotile (CH) or crocidolite (CR) showed acquired resistance to asbestos-induced apoptosis following transient and high-dose re-exposure with fibers. These sublines in addition to other immune cells such as natural killer cells or cytotoxic T lymphocytes exposed to asbestos showed a reduction in anti-tumor immunity. In this study, the expression of genes and molecules related to antioxidative stress was examined. Furthermore, complexes related to oxidative phosphorylation were investigated since the production of reactive oxygen species (ROS) is important when considering the effects of asbestos in carcinogenesis and the mechanisms involved in resistance to asbestos-induced apoptosis. In sublines continuously exposed to CH or CR, the expression of thioredoxin decreased. Interestingly, nicotinamide nucleotide transhydrogenase (NNT) expression was markedly enhanced. Thus, knockdown of NNT was then performed. Although the knockdown clones did not show any changes in proliferation or occurrence of apoptosis, these clones showed recovery of ROS production with returning NADPH/NADP+ ratio that increased with decreased production of ROS in continuously exposed sublines. These results indicated that NNT is a key factor in preventing ROS-induced cytotoxicity in T cells continuously exposed to asbestos. Considering that these sublines showed a reduction in anti-tumor immunity, modification of NNT may contribute to recovery of the anti-tumor effects in asbestos-exposed T cells

Blind suppression of nonstationary diffuse noise based on spatial covariance matrix decomposition

International audienceWe propose methods for blind suppression of nonstationary diffuse noise based on decomposition of the observed spatial covariance matrix into signal and noise parts. In modeling noise to regularize the ill-posed decomposition problem, we exploit spatial invariance (isotropy) instead of temporal invariance (stationarity). The isotropy assumption is that the spatial cross-spectrum of noise is dependent on the distance between microphones and independent of the direction between them. We propose methods for spatial covariance matrix decomposition based on least squares and maximum likelihood estimation. The methods are validated on real-world recordings

Trials for Risk Assessment of Japanese Encephalitis Based on Serologic Surveys of Wild Animals

Flavivirus Encephaliti