Chemiluminescence behavior of fluorescent aromatics tethered 9-methylidene-10-methylacridans involving chemiluminescence resonance energy transfer (CRET) quenching

The chemiluminescence (CL) behavior, observed in the singlet oxygenation of three fluorescent aromatics tethered 9-methylidene-10-methylacridans bearing the pyrene, perylene, and stilbene moieties, was investigated. The CL spectrum of 9-(perylen-3′-ylidene)-10-methylacridan displayed a red-shifted emission different from the fluorescent products, while 9-(pyren-1′-ylidene)-10-methylacridan and 9-(4′-styrylbenzylidene)-10-methylacridan produced very weak CLs. A chemiluminescence resonance energy transfer (CRET) quenching of the excited aromatic aldehydes by the acridans remaining as the unreacted reactants was found to result in these unexpected CL behaviors.ArticleTetrahedron Letters. 54(11):1338-1343 (2013)journal articl

Survey of understanding and awareness of fertility preservation in pediatric patients: Is conversation about fertility preservation unpleasant for pediatric patients?

ObjectiveTo verify understanding and awareness of fertility preservation (FP) in pediatric patients undergoing FP treatments.MethodsA questionnaire survey was conducted before and after explanation of fertility issues and FP treatments for patients 6–17 years old who visited or were hospitalized for the purpose of ovarian tissue cryopreservation (OTC) or oocyte cryopreservation (OC), or sperm cryopreservation between October 2018 and April 2022. This study was approved by the institutional review board at St. Marianna University School of Medicine (No. 4123, UMIN000046125).ResultParticipants in the study comprised 36 children (34 girls, 2 boys). Overall mean age was 13.3 ± 3.0 years. The underlying diseases were diverse, with leukemia in 14 patients (38.9%), brain tumor in 4 patients (11.1%). The questionnaire survey before the explanation showed that 19 patients (52.8%) wanted to have children in the future, but 15 (41.7%) were unsure of future wishes to raise children. And most children expressed some degree of understanding of the treatment being planned for the underlying disease (34, 94.4%). Similarly, most children understood that the treatment would affect their fertility (33, 91.7%). When asked if they would like to hear a story about how to become a mother or father after FP which including information of FP, half answered “Don’t mind” (18, 50.0%). After being provided with information about FP treatment, all participants answered that they understood the adverse effects on fertility of treatments for the underlying disease. Regarding FP treatment, 32 children (88.9%) expressed understanding for FP and 26 (72.2%) wished to receive FP. “Fear” and “Pain” and “Costs” were frequently cited as concerns about FP. Following explanations, 33 children (91.7%) answered “Happy I heard the story” and no children answered, “Wish I hadn’t heard the story”. Finally, 28 of the 34 girls (82.4%) underwent OTC and one girl underwent OC.DiscussionThe fact that all patients responded positively to the explanations of FP treatment is very informative. This is considered largely attributable to the patients themselves being involved in the decision-making process for FP.ConclusionsExplanations of FP for children appear valid if age-appropriate explanations are provided

Role of Sphingosine-1-Phosphate in β-adrenoceptor Desensitization via Ca2+ Sensitization in Airway Smooth Muscle

Background: The correlation between inflammatory cells and airway smooth muscle plays fundamental roles in the pathophysiology of asthma. This study was designed to determine whether pre-exposure of airway smooth muscle to sphingosine-1-phosphate (S1P), which is released from mast cells by allergic reactions, causes a deterioration of β-adrenoceptor function. Methods: Isometric tension and the ratio of fluorescence intensities at 340 and 380 nm (F340/F380), an indicator of intracellular Ca2+ levels, were simultaneously measured using fura-2 loaded guinea-pig tracheal tissues. Intracellular cAMP levels were also measured. Results: Pre-exposure to S1P caused a reduction in the inhibitory effects of 0.3 μM isoprenaline, a β-adrenoceptor agonist, and 10 μM forskolin, a direct activator of adenylyl cyclase, against 1 μM methacholine-induced contraction in concentration- and time- dependent manners. In contrast, the values of F340/F380 were not augmented under this experimental condition. After incubation with S1P in the presence of 0.001-1 μM Y-27632, a Rho-kinase inhibitor, the reduced responsiveness to forskolin induced by S1P was reversed in a concentration-dependent manner. Moreover, pre-treatment with pertussis toxin (PTX), an inhibitor of Gi, suppressed the loss of forskolin-induced relaxation induced by S1P. Pre-exposure to S1P markedly inhibited the augmentation of cAMP accumulation induced by forskolin. However, addition of Y-27632 and pre-exposure to PTX returned forsokin-induced cAMP accumulation to the control level. Conclusions: Pre-exposure to S1P causes heterologus desensitization of β-adrenoceptors by increasing the sensitivity of airway smooth muscle to intracellular Ca2+. Ca2+ sensitization regulated by Gi and Rho-kinase is involved in this phenomenon

Chemiluminescence behavior of fluorescent aromatics tethered 9-methylidene-10-methylacridans involving chemiluminescence resonance energy transfer (CRET) quenching

The chemiluminescence (CL) behavior, observed in the singlet oxygenation of three fluorescent aromatics tethered 9-methylidene-10-methylacridans bearing the pyrene, perylene, and stilbene moieties, was investigated. The CL spectrum of 9-(perylen-3′-ylidene)-10-methylacridan displayed a red-shifted emission different from the fluorescent products, while 9-(pyren-1′-ylidene)-10-methylacridan and 9-(4′-styrylbenzylidene)-10-methylacridan produced very weak CLs. A chemiluminescence resonance energy transfer (CRET) quenching of the excited aromatic aldehydes by the acridans remaining as the unreacted reactants was found to result in these unexpected CL behaviors.ArticleTetrahedron Letters. 54(11):1338-1343 (2013)journal articl