Energy metabolism during the maturation of reticulocyte in vitro

1. For the purpose to clarify the mechanism of the revolutional changes in energy metabolism during the reticulocyte maturation the metabolisms of glucose and of the pentose moieties of acid soluble nucleotides have been observed on rabbit reticulocytes incubated in vitro under various conditions. 2. The maturation of reticulocyte proceeds by using the energy produced by aerobic glycolysis and is arrested in the glucose deficient medium, but the pentose moieties of purine nucleotide and nucleoside added exogenously serve as the energy source for reticulocyte maturation even in the absence of glucose. 3. The test on the utility efficiency of glucose and inosine as the energy source for reticulocyte maturation revealed that glucose is used more effectively than the pentose moiety of inosine under aerobic condition, which is advantageous for reticulocyte maturation, and vice versa under anaerobic condition, which is comparable to the metabolism of mature red cell. 4. From these results it has been suggested that the maturation of reticulocyte is the process of degradation of RNA and acid soluble nucleotides supported by the aerobic glycolysis, where the degradation products of RNA and acid soluble purine nucleotides provide the purine derivatives as the material for ATP synthesis (36) and the pentose moieties as energy source. 5. A possible mechanism for the superior utility of glucose to nucleoside pentose during reticulocyte maturation and vice versa in mature red cell has been discussed.</p

Word Processing Is Faster than Picture Processing in Alzheimer’s Disease

Objective. Alzheimer’s disease (AD) is characterized by a slow progressive impairment of episodic memory. Many studies have shown that AD exhibits deterioration of semantic memory during the course of disease progression. We previously reported that AD patients exhibited severe access disorders in the semantic memory system, using the Momentary Presentation Task (20 or 300 ms). In this study, we studied access disorder in patients with AD by the use of object difference (pictures vs words) methods. Methods. 56 patients with probable AD (NINCDS-ADRDA, mean age 79.0 years) and 11 healthy controls (HC) (mean age 67.0 years) were studied. Ten pictures and 10 corresponding Japanese Hiragana words were presented arbitrarily for 20 and 300 ms on the monitor screen which were correctly named at the usual confrontation setting (i.e., semantic memory preserved). They were asked to name the pictures or to read the words or nonsense syllables aloud. Results. The AD group showed significantly lower scores than the HC group, especially for the 20 ms condition. For the type of stimuli, the AD patients had better performances for words > pictures > nonsense syllables, although no differences for the HC group. The effect of AD severity was noted, moderate > severe stage. Conclusions. Our results suggested that the processing speed in AD patients may have reduced, even if the semantic memory were preserved. These data indicated that the difference in the processing speeds by the type of stimuli (pictures, words, and nonsense syllables) may be a character of AD patients

Analytical Performance of a Highly Sensitive System to Detect Gene Variants Using Next-Generation Sequencing for Lung Cancer Companion Diagnostics

The recent increase in the number of molecular targeted agents for lung cancer has led to the demand for the simultaneous testing of multiple genes. Although gene panels using next-generation sequencing (NGS) are ideal, conventional panels require a high tumor content, and biopsy samples often do not meet this requirement. We developed a new NGS panel, called compact panel, characterized by high sensitivity, with detection limits for mutations of 0.14%, 0.20%, 0.48%, 0.24%, and 0.20% for EGFR exon 19 deletion, L858R, T790M, BRAF V600E, and KRAS G12C, respectively. Mutation detection also had a high quantitative ability, with correlation coefficients ranging from 0.966 to 0.992. The threshold for fusion detection was 1%. The panel exhibited good concordance with the approved tests. The identity rates were as follows: EGFR positive, 100% (95% confidence interval, 95.5–100); EGFR negative, 90.9 (82.2–96.3); BRAF positive, 100 (59.0–100); BRAF negative, 100 (94.9–100); KRAS G12C positive, 100 (92.7–100); KRAS G12C negative, 100 (93.0–100); ALK positive, 96.7 (83.8–99.9); ALK negative, 98.4 (97.2–99.2); ROS1 positive, 100 (66.4–100); ROS1 negative, 99.0 (94.6–100); MET positive, 98.0 (89.0–99.9); MET negative 100 (92.8–100); RET positive, 93.8 (69.8–100); RET negative, 100 (94.9–100). The analytical performance showed that the panel could handle various types of biopsy samples obtained by routine clinical practice without requiring strict pathological monitoring, as in the case of conventional NGS panels