バイヨウ サイボウ トウケツ ホゾン ニ タイスル ラクトアミド ノ トウケツ ホゴ サヨウ

　ジメチルスルホキシド（DMSO）は、培養哺乳類細胞凍結保存の凍結保護剤として一般的に用いられているが、DNAメチル化やヒストンの修飾によって、一部の細胞では分化を引き起こすことが知られている。凍結保存時の培養細胞の安定した分化形質保持には、メチル化を起こすDMSO以外の凍結保護剤の使用が必要である。 細胞毒性が低く、動物精子凍結保存に効果的であることが示されたアミド化合物が、同様に哺乳類の培養細胞の凍結保存での凍結保護作用があるかを（8種類のアミド化合物で）培養マウス血管内皮細胞を用いて調べた。 調べたアミド化合物の中で、アセトアミドとラクトアミドの2種類が培養細胞に対しての凍結保護作用があり、最も効果的だったのは、濃度が1.5Mのラクトアミドであった。培養細胞の凍結保存に類しては、浸透圧ストレスを避ける必要があるため、1.5Mラクトアミド溶液を作成する際の溶媒を各希釈率のリン酸緩衝塩類溶液（PBS）とし、浸透圧を変えた凍結保存液で凍結細胞の生存率を調べた。 その結果、0.4倍濃度のPBSが浸透ストレスを最小にし、生存率を高く保つことができた。凍結保存培地に高分子量材料を追加すると細胞の生存率が改善するこが知られているので、牛血清アルブミン（BSA）、ヒドロキシエチルスターチ、デキストランの効果を調べた。 その結果、ラクトアミドを用いた凍結保存培地は、0.4×PBSを用いた1.5Mラクトアミド溶液に1％のBSAを添加した場合、DMSOの凍結保護作用に匹敵する凍結保護作用を示すことが分かった

〔研究ノート〕 マウスのエタノール代謝における柿茶濃縮物の影響

Hangovers resulting from excessive alcohol consumption are largely caused by the acetaldehyde produced during alcohol metabolism. Persimmon fruit and persimmon leaf extracts are generally regarded as useful for "sobering up" and for reducing blood pressure. It is believed that these effects are due to the activity of polyphenols and tannin. Tannin, a component that gives persimmons and persimmon tea their astringency, is a water-soluble plant polyphenol that forms water-insoluble complexes with proteins, alkaloids, heavy metals, and other compounds. To identify the novel physiological functions of persimmon leaf extracts, concentrated extracts of persimmon leaves were prepared by extracting leaves with boiling water. The efficacy of the extracts in preventing alcohol-induced hangovers was determined by monitoring acetaldehyde concentrations in the blood of mice that first had been administered persimmon leaf extract, and then were administered ethanol. The results of the study indicate that acetaldehyde production can be suppressed by administering persimmon tea prior to alcohol intake

Effects of Energy Delivery Guided by Indirect Calorimetry in Critically Ill Patients: A Systematic Review and Meta-Analysis

Background: The utility of using indirect calorimetry (IC) to estimate energy needs and methods for its application to this purpose remain unclear. This systematic review investigated whether using IC to estimate energy expenditure in critically ill patients is more meaningful for improving survival than other estimation methods. Methods: Comprehensive searches were conducted in MEDLINE using PubMed, Cochrane Central Register of Controlled Trials, and Igaku-Chuo-Zasshi up to March 2023. Results: Nine RCTs involving 1178 patients were included in the meta-analysis. The evidence obtained suggested that energy delivery by IC improved short-term mortality (risk ratio, 0.86; 95% confidence interval [CI], 0.70 to 1.06). However, the use of IC did not appear to affect the length of ICU stay (mean difference [MD], 0.86; 95% CI, −0.98 to 2.70) or the duration of mechanical ventilation (MD, 0.66; 95% CI, −0.39 to 1.72). Post hoc analyses using short-term mortality as the outcome found no significant difference by target calories in resting energy expenditure, whereas more frequent IC estimates were associated with lower short-term mortality and were more effective in mechanically ventilated patients. Conclusions: This updated meta-analysis revealed that the use of IC may improve short-term mortality in patients with critical illness and did not increase adverse events