Edge-Functionalization of Pyrene as a Miniature Graphene via Friedel–Crafts Acylation Reaction in Poly(Phosphoric Acid)

The feasibility of edge-functionalization of graphite was tested via the model reaction between pyrene and 4-(2,4,6-trimethylphenyloxy)benzamide (TMPBA) in poly(phosphoric acid) (PPA)/phosphorous pentoxide (P2O5) medium. The functionalization was confirmed by various characterization techniques. On the basis of the model study, the reaction condition could be extended to the edge-functionalization of graphite with TMPBA. Preliminary results showed that the resultant TMPBA-grafted graphite (graphite-g-TMPBA) was found to be readily dispersible in N-methyl-2-pyrrolidone (NMP) and can be used as a precursor for edge-functionalized graphene (EFG)

P-Element Homing Is Facilitated by engrailed Polycomb-Group Response Elements in Drosophila melanogaster

P-element vectors are commonly used to make transgenic Drosophila and generally insert in the genome in a nonselective manner. However, when specific fragments of regulatory DNA from a few Drosophila genes are incorporated into P-transposons, they cause the vectors to be inserted near the gene from which the DNA fragment was derived. This is called P-element homing. We mapped the minimal DNA fragment that could mediate homing to the engrailed/invected region of the genome. A 1.6 kb fragment of engrailed regulatory DNA that contains two Polycomb-group response elements (PREs) was sufficient for homing. We made flies that contain a 1.5kb deletion of engrailed DNA (enΔ1.5) in situ, including the PREs and the majority of the fragment that mediates homing. Remarkably, homing still occurs onto the enΔ1. 5 chromosome. In addition to homing to en, P[en] inserts near Polycomb group target genes at an increased frequency compared to P[EPgy2], a vector used to generate 18,214 insertions for the Drosophila gene disruption project. We suggest that homing is mediated by interactions between multiple proteins bound to the homing fragment and proteins bound to multiple areas of the engrailed/invected chromatin domain. Chromatin structure may also play a role in homing

A Report on a Nationwide Surveillance System for Pediatric Acute Hepatitis of Unknown Etiology in Korea

Background: Several cases of pediatric acute hepatitis of unknown etiology related to adenoviral infections have been reported in Europe since January 2022. The aim of this study was to compare the incidence, severity, possible etiology, and prognosis of the disease with those in the past in Korea. Methods: The surveillance group collected data between May and November 2022 using a surveillance system. Acute hepatitis of unknown etiology was defined in patients aged < 16 years with a serum transaminase level > 500 IU/L, not due to hepatitis A-E or other underlying causes. For comparison, data from 18 university hospitals were retrospectively collected as a control group between January 2021 and April 2022. Results: We enrolled 270 patients (mean age, 5 years). The most common symptom was fever. However, the incidence was similar between 2021 and 2022. Liver function test results, number of patients with acute liver failure (ALF), liver transplantation (LT), death, and adenovirus detection rates did not differ between the two groups. None of the adenoviruspositive patients in either group experienced ALF, LT, or death. In the surveillance group, adenovirus-associated virus-2 was detected in four patients, one of whom underwent LT. Patients with an unknown etiology showed significantly higher bilirubin levels, a lower platelet count, and a higher LT rate than patients with a possible etiology. Conclusion: The incidence of pediatric acute hepatitis of unknown etiology and adenovirus detection rate have not increased in Korea

Mass propagation of microtubers from suspension cultures of Pinellia ternata cells and quantitative analysis of succinic acid in Pinellia tubers

The conditions for efficient tuber production from suspension cultures of Pinellia ternata cells which is one of medicinal herbs were established and succinic acid in tubers propagated in vitro was determined. Leaf explants formed white nodular structures and off-white calluses at a frequency of 90.6 % when cultured on Murashige and Skoog medium supplemented with 0.54 μM α-naphthaleneacetic acid (NAA); however, this frequency declined substantially with increasing NAA concentration, up to 16.2 μM, at which the frequency reached zero percent. In combination treatments with 4.44 μM 6-benzyladenine (BA) and NAA, however, the frequency of white nodular structure and off-white callus formation from leaf explants did not decrease, even at 16.2 μM NAA. Suspension cultures of P. ternata cells were established from leaf-derived off-white calluses in MS liquid medium containing 5.4 μM NAA and 4.44 μM BA. Upon plating onto MS basal medium, over 90 % of cell aggregates gave rise to microtubers and developed into plantlets. Regenerated plantlets were transplanted in potting soil and grown to maturity in a growth chamber, with a survival rate of >90 %. The highest succinic acid content in suspension culture-derived microtubers was 45 g/kg of extract. Compared with wild P. ternata medicinal tubers, the succinic acid content was very similar. The in vitro P. ternata microtuber proliferation system established in this study is thus an efficient alternative for the mass production of medicinal tubers. © 2015, Korean Society for Plant Biotechnology and Springer Japan.