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Background:In Japan, where infertility treatment is now covered by insurance, appropriate protocols for patients with diminished ovarian reserve (DOR) based on treatment outcomes and cost-effectiveness must be selected. Therefore, this study aims to provide information on the outcomes and cost-effectiveness of conventional ovarian stimulation and mild stimulation for patients with DOR in Japan.Methods:Data from 66 women who underwent first oocyte retrieval at Showa University Hospital between May 2019 and November 2023 were analyzed.Results:The clomiphene citrate (CC) group used significantly fewer gonadotropins and incurred lower costs than the conventional ovarian stimulation group while achieving comparable clinical outcomes, including cumulative live birth rates.Conclusions:CC-based minimal stimulation is a cost-effective alternative to conventional ovarian stimulation for patients with low ovarian reserve without compromising clinical efficacy. Further randomized controlled trials are required to confirm these findings and optimize protocols for this population.

The Japan Atomic Energy Agency has been developing centrifugal contactors for solvent extraction to apply to next-generation reprocessing plants. The centrifugal contactor has some attractive advantages such as more compact design and shorter liquid residence times than conventional contactors. Many kinetic studies using a miniature centrifugal contactor have been carried out worldwide. However, there are few engineering-scale studies in which stage efficiencies, transition behavior of concentration profiles, and robustness under maloperation conditions have been comprehensively discussed for a contactor cascade system. In this study, we carried out extraction and stripping tests of an engineering-scale centrifugal contactor cascade system based on a flowsheet of 10 kg-HM/h using uranyl nitrate solution. As a result, the stage efficiencies on uranium extraction and stripping were quite high, nearly 100% for extraction and 97–98% for stripping. The uranium concentration profiles became stable within 10 minutes for both extraction and stripping sections. No overflow or entrainment was observed under normal operation during the extraction and stripping tests. During the stripping test, it was estimated that an increase in temperature of the feed stripping solution from 308 to 333K or a decrease in the flow rate ratio of the organic to aqueous phase from 1.0 to 0.8 corresponded to the distribution capacity of the two contactors. The maloperation test, in which a motor at a stage of the contactor cascade system was intentionally stopped, showed that the system could maintain stable operation with no emergency shutdown following the installation of at least two additional stages.

Smooth muscle myosin light chain (LC) can be phosphorylated by myosin light chain kinase (MLCK) at Ser 19and Thr 18and by protein kinase C (PKC) at Thr 9and Ser 1or Ser 2under the in vitro assay conditions. Conversion of PKC to the spontaneously active protein kinase M (PKM) by proteolysis resulted in a change in the substrate specificity of the kinase. PKM phosphorylated both sets of sites in LC recognized by MLCK and PKC as analyzed by peptide mapping analysis. The PKM-catalyzed phosphorylation of these sites was not greatly affected by a MLCK inhibitor, ML-9, nor by the activators of MLCK, Ca 2+and calmodulin.

Three protein kinase C (PKC) isozymes, type I, II, and III, have been identified as the major Ca2+/phospholipid-stimulated protein kinases in the various animal tissues. Based on the immunochemical analysis it was demonstrated that PKC I was encoded by γ cDNA, PKC II by the alternatively spliced βI and βII cDNAs, and PKC III by α cDNA. The expression of these enzymes appears to be tissue-specific and developmentally regulated. The central nervous system expresses high level of all three isozymes and the peripheral tissues mainly PKC II and III. During brain development, the expression of PKC I appears to follow the progress of synaptogenesis, whereas PKC II and III increase progressively from fetus up to 2–3 weeks of age. The level of PKC I in adult brain is highest in the cerebellum, hippocampus, amygdala, and cerebral cortex especially in those cortical regions being important for visual information processing and storage. The role of PKC II and III in cellular regulation was investigated by treatment of rat basophilic leukemia cells with the phorbol ester, phorbol 12-myristate 13-acetate. This phorbol ester caused a faster degradation of PKC II than III, indicating a differential down-regulation of these two enzymes by this compound. The results presented in this study support the contention that each species of PKC has a distinct function in the regulation of a variety of cellular processes.

Smooth muscle myosin light chain (LC) can be phosphorylated by myosin light chain kinase (MLCK) at Ser19and Thr18and by protein kinase C (PKC) at Thr9and Ser1or Ser2under the in vitro assay conditions. Conversion of PKC to the spontaneously active protein kinase M (PKM) by proteolysis resulted in a change in the substrate specificity of the kinase. PKM phosphorylated both sets of sites in LC recognized by MLCK and PKC as analyzed by peptide mapping analysis. The PKM‐catalyzed phosphorylation of these sites was not greatly affected by a MLCK inhibitor, ML‐9, nor by the activators of MLCK, Ca2+and calmodulin.

Magainins are a family of antimicrobial peptides present in the skin extracts of Xenopus laevis. Both magainin-1 and -2 do not have any significant effect on the activity of protein kinase C (PKC). Magainin-2 was found to be readily phosphorylated by PKC to 0.5 mol- 32P/mol of peptide. Neither magainin-1, which has a sequence of S 8AGK and not S 8AKK as in the case of magainin-2, nor the magainin-2 analogue with substitution of Ala for Ser 8was phosphorylated by the kinase, suggesting that Ser 8is the phosphorylation site of magainin-2. One synthetic analogue of magainin, designated magainin B, which has a greater tendency for α-helix formation in non-aqueous environment than the parent peptide resulting from substitution of Ser 8, Gly 13, and Gly 18with Ala in magainin-2-amide, is a potent inhibitor of PKC. This peptide inhibits all three PKC isozymes with IC 50less than 20 μM. Magainin B also inhibits the binding of [ 3H]phorbol 12,13-dibutyrate to the kinase. These results suggest that magainin-2 may be modified by PKC through phosphorylation and that certain synthetic analogues of magainins may be used as inhibitors of PKC.

Magainins are a family of antimicrobial peptides present in the skin extracts of Xenopus laevis. Both magainin‐1 and ‐2 do not have any significant effect on the activity of protein kinase C (PKC). Magainin‐2 was found to be readily phosphorylated by PKC to 0.5 mol‐32P/mol of peptide. Neither magainin‐1, which has a sequence of S8AGK and not S8AKK as in the case of magainin‐2, nor the magainin‐2 analogue with substitution of Ala for Ser8was phosphorylated by the kinase, suggesting that Ser8is the phosphorylation site of magainin‐2. One synthetic analogue of magainin, designated magainin B, which has a greater tendency for α‐helix formation in non‐aqueous environment than the parent peptide resulting from substitution of Ser8, Gly13, and Gly18with Ala in magainin‐2‐amide, is a potent inhibitor of PKC. This peptide inhibits all three PKC isozymes with IC50less than 20 μM. Magainin B also inhibits the binding of [3H]phorbol 12,13‐dibutyrate to the kinase. These results suggest that magainin‐2 may be modified by PKC through phosphorylation and that certain synthetic analogues of magainins may be used as inhibitors of PKC.