Effects of temperature and stem length on changes in carbohydrate content in summer-grown cut chrysanthemums during development and senescence

Abstract Changes in the carbohydrate content in capitula, stems, and leaves were investigated in cut chrysanthemum Dendranthema ×grandiflorum (Ramat.) Kitamura 'Seiun' plants with 60-cm stems held at 20, 25 and 30°C for 27 days postharvest. In addition, plants with 20-cm stems were studied at 25°C. Diameter of the capitula, the angle of the florets, fresh weight (FW) and dry weight (DW) increased more slowly at 30°C/60 cm and 25°C/20 cm than at 20°C/60 cm and 25°C/60 cm. The number of well-developed florets was notably smaller, and the number of tubular-shaped florets was larger at 30°C/60 cm than at 20°C/60 cm. Glucose and fructose concentrations in the capitula increased, although they decreased midway through treatment at 30°C/60 cm. Fructose concentrations in the stems, and in particular in the middle stems, were greater at 30°C/60 cm than at 20°C/60 cm and 25°C/60 cm. The increase in the total DW during treatments suggested that photosynthesis was occurring in the leaves and that photosynthates were a main source for the capitula and stems. Development of the capitula was suppressed, which was related to the reduction in its carbohydrate supply. Wilting of petals was not accelerated at high temperatures and with short-stem treatments

Jet spectroscopy of buckybowl: Electronic and vibrational structures in the S0 and S1 states of triphenylene and sumanene

Sumanene is a typical buckybowl molecule with C3v symmetry. We observed a fluorescence excitation spectrum and a dispersed fluorescence spectrum of sumanene in a supersonic jet. Bowl effects were clarified by comparing the spectra with those of triphenylene (D3h symmetry), which is a planar prototype of nonplanar sumanene. The S1 (1)A1 ← S0 (1)A1 transition is symmetry allowed. We found the 00 (0) band in the fluorescence excitation spectrum at 357.78 nm; this band was missing in the forbidden S1 (1)A1 (') ← S0 (1)A1 (') transition of triphenylene. The transition moment was shown to be along the oblate symmetric top axis (out of plane) by the observed rotational contour. A large number of vibronic bands were observed, unlike in triphenylene. Some were considered to be out-of-plane vibrational modes, which lead to a bowl-to-bowl inversion reaction assisted by in-plane vibrations. We found that the vibronic bands were markedly weak in the high energy region of triphenylene-d12. This indicates that the fluorescence quantum yield is very low at the high vibrational levels in the S1 state due to the rapid radiationless transition. The main process is considered to be internal conversion to the S0 state. The nonplanar structural distortion may also enhance radiationless transitions. We could not, however, observe weakening of the vibronic bands in the fluorescence excitation spectrum of sumanene

Subcritical Methanol Extraction of the Stone of Japanese Apricot Prunus mume Sieb. et Zucc.

The pits of Japanese apricot, Prunus mume Sieb. et Zucc., which are composed of stones, husks, kernels, and seeds, are unused by-products of the processing industry in Japan. The processing of Japanese apricot fruits generates huge amounts of waste pits, which are disposed of in landfills or, to a lesser extent, burned to form charcoal. Mume stones mainly consist of cellulose, hemicellulose, and lignin. Herein, we attempted to solubilize the wood-like carapace (stone) encasing the pit by subcritical fluid extraction with the aim of extracting useful chemicals. The characteristics of the main phenolic constituents were elucidated by liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) analyses. The degrees of solubility for various treatments (190 °C; 3 h) were determined as follows: subcritical water (54.9%), subcritical 50% methanol (65.5%), subcritical 90% methanol (37.6%), subcritical methanol (23.6%), and subcritical isopropyl alcohol (14.4%). Syringaldehyde, sinapyl alcohol, coniferyl alcohol methyl ether, sinapyl alcohol methyl ether, 5-(hydroxymethyl)-2-furfural, and furfural were present in the subcritical 90% methanol extract. Coniferyl and sinapyl alcohols (monolignols) are source materials for the biosynthesis of lignin, and syringaldehyde occur in trace amounts in wood. Our current findings provide a solubilization method that allows the main phenolic constituents of the pits to be extracted under mild conditions. This technique for obtaining subcritical extracts shows great potential for further applications

Azacitidine is a potential therapeutic drug for pyridoxine-refractory female X-linked sideroblastic anemia

女性のX連鎖性鉄芽球性貧血患者さん由来のiPS細胞を使った病態モデルの作製と治療薬候補の発見. 京都大学プレスリリース. 2021-12-01.X-linked sideroblastic anemia (XLSA) is associated with mutations in the erythroid-specific δ-aminolevulinic acid synthase (ALAS2) gene. Treatment for XLSA is mainly supportive, except in pyridoxine-responsive patients. Female XLSA often represents a late onset of severe anemia, mostly due to the acquired skewing of X-chromosome inactivation. Here, we successfully generated active wild-type and mutant ALAS2 induced pluripotent stem cell (iPSC) lines from the peripheral blood cells of an affected mother and two daughters in a family with pyridoxine-resistant XLSA due to a heterozygous ALAS2 missense mutation (R227C). The erythroid differentiation potential was severely impaired in active mutant iPSC lines compared to that in active wild-type iPSC lines. Most of the active mutant iPSC-derived erythroblasts revealed an immature morphological phenotype, and some showed dysplasia and perinuclear iron deposits. Additionally, globin and HO-1 expression and heme biosynthesis in active mutant erythroblasts were severely impaired compared to that in active wild-type erythroblasts. Furthermore, genes associated with erythroblast maturation and karyopyknosis showed significantly reduced expression in active mutant erythroblasts, recapitulating the maturation defects. Notably, the erythroid differentiation ability and hemoglobin expression of active mutant iPSC-derived hematopoietic progenitor cells (HPCs) were improved by the administration of δ-aminolevulinic acid, verifying the suitability of the cells for drug testing. Administration of a DNA demethylating agent, azacitidine, reactivated the silent wild-type ALAS2 allele in active mutant HPCs and ameliorated erythroid differentiation defects, suggesting that azacitidine is a potential novel therapeutic drug for female XLSA. Our patient-specific iPSC platform provides novel biological and therapeutic insights for XLSA