Boron-based multiple-resonance (MR) emitters exhibit the advantages of narrowband emission, high absolute photoluminescence quantum yield, thermally activated delayed fluorescence (TADF), and ...sufficient stability during the operation of organic light-emitting diodes (OLEDs). Thus, such MR emitters have been widely applied as blue emitters in triplet-triplet-annihilation-driven fluorescent devices used in smartphones and televisions. Moreover, they hold great promise as TADF or terminal emitters in TADF-assisted fluorescence or phosphor-sensitised fluorescent OLEDs. Herein we comprehensively review organoboron-based MR emitters based on their synthetic strategies, clarify structure-photophysical property correlations, and provide design guidelines and future development prospects.
This review highlights organoboron-based multiple-resonance compounds' synthetic strategies classified as one-pot borylation, one-shot borylation, and late-stage functionalisation, and explores material structure-photophysical property correlations.
Neonatal hypoxic-ischaemic encephalopathy (HIE) is a serious condition; many survivors develop neurological impairments, including cerebral palsy and intellectual disability. Preclinical studies show ...that the systemic administration of umbilical cord blood cells (UCBCs) is beneficial for neonatal HIE. We conducted a single-arm clinical study to examine the feasibility and safety of intravenous infusion of autologous UCBCs for newborns with HIE. When a neonate was born with severe asphyxia, the UCB was collected, volume-reduced, and divided into three doses. The processed UCB was infused at 12-24, 36-48, and 60-72 hours after the birth. The designed enrolment was six newborns. All six newborns received UCBC therapy strictly adhering to the study protocol together with therapeutic hypothermia. The physiological parameters and peripheral blood parameters did not change much between pre- and postinfusion. There were no serious adverse events that might be related to cell therapy. At 30 days of age, the six infants survived without circulatory or respiratory support. At 18 months of age, neurofunctional development was normal without any impairment in four infants and delayed with cerebral palsy in two infants. This pilot study shows that autologous UCBC therapy is feasible and safe.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Multiple-resonance thermally activated delayed fluorescence (MR-TADF) emitters have emerged as an important component of organic light-emitting diodes (OLEDs) because of their narrowband emission and ...high exciton utilization efficiency. However, the chemical space of MR-TADF emitters remains mostly unexplored because of the lack of suitable synthetic protocols. Herein, we demonstrate a sequential multiple borylation reaction that provides new synthetically accessible chemical space. ω-DABNA, the proof-of-concept material, exhibited narrowband green TADF with a full width at half-maximum of 22 nm and a small singlet–triplet energy gap of 13 meV. The OLED employing it as an emitter exhibited electroluminescence at 512 nm, with Commission International de l’Éclairage coordinates of (0.13, 0.73) and a high external quantum efficiency (EQE) of 31.1%. Moreover, the device showed minimum efficiency roll-off, with an EQE of 29.4% at 1000 cd m–2.
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IJS, KILJ, NUK, PNG, UL, UM
To evaluate the impact of maternal hypertensive disorders of pregnancy (HDP) on mortality and neurological outcomes in extremely and very preterm infants using a nationwide neonatal database in ...Japan. This population-based retrospective study was based on an analysis of data collected by the Neonatal Research Network of Japan from 2003 to 2015 of neonates weighing 1,500 g or less at birth, between 22 and 31 weeks' gestation. A total of 21,659 infants were randomly divided into two groups, HDP (n = 4,584) and non-HDP (n = 4,584), at a ratio of 1:1 after stratification by four factors including maternal age, parity, weeks of gestation, and year of delivery. Short-term (neonatal period) and medium-term (3 years of age) mortality and neurological outcomes were compared between the two groups by logistic regression analyses. In univariate analysis, HDP was associated with an increased risk for in-hospital death (crude odds ratio OR, 1.31; 95% confidence interval, 1.04-1.63) and a decreased risk for severe intraventricular haemorrhage (0.68; 0.53-0.87) and periventricular leukomalacia (0.60; 0.48-0.77). In multivariate analysis, HDP was significantly associated with a lower risk for in-hospital death (adjusted OR, 0.61; 0.47-0.80), severe intraventricular haemorrhage (0.47; 0.35-0.63), periventricular leukomalacia (0.59; 0.45-0.78), neonatal seizures (0.40; 0.28-0.57) and cerebral palsy (0.70; 0.52-0.95) at 3 years after adjustment for covariates including birth weight. These results were consistent with those of additional analyses, which excluded cases with histological chorioamnionitis and which divided the infants into two subgroups (22-27 gestational weeks and 28-31 gestational weeks). Maternal HDP was associated with an increased risk for in-hospital death without adjusting for covariates, but it was also associated with a lower risk for mortality and adverse neurological outcomes in extremely and very preterm infants if all covariates except HDP were identical.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
BN-embedded nonacene, tridecacene, and heptadecacene frameworks were constructed using one-shot quadruple, sextuple, and octuple borylation reactions, respectively. The key to success is the ...judicious choice of borylating reagents and long-chain alkyl-substituted carbazolyl groups as boron-trapping groups, which suppressed the decrease in HOMO energy and insolubilization associated with borylation. Based on the product yields, each electrophilic C–H borylation proceeded in >99% yield, which is the best efficiency reported so far for C–H borylation reactions. Owing to the multiple resonance effects of boron and nitrogen, the prepared acenes exhibited ultra-narrowband green thermally activated delayed fluorescence with full-width at half-maximum of 12–16 nm; moreover, their k RISC values were in the order of 105 s–1. We fabricated an organic light-emitting diode by employing the nonacene as an emitter, which exhibited high external quantum efficiency (EQE) of 28.7%. The device also showed a minimum efficiency roll-off with an EQE of 25.8% at 1000 cd m–2.
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IJS, KILJ, NUK, PNG, UL, UM
Perinatal hypoxic ischemic encephalopathy (HIE) results in serious neurological dysfunction and mortality. Clinical trials of multilineage-differentiating stress enduring cells (Muse cells) have ...commenced in stroke using intravenous delivery of donor-derived Muse cells. Here, we investigated the therapeutic effects of human Muse cells in an HIE model. Seven-day-old rats underwent ligation of the left carotid artery then were exposed to 8% oxygen for 60 min, and 72 hours later intravenously transplanted with 1 × 104 of human-Muse and -non-Muse cells, collected from bone marrow-mesenchymal stem cells as stage-specific embryonic antigen-3 (SSEA-3)+ and −, respectively, or saline (vehicle) without immunosuppression. Human-specific probe revealed Muse cells distributed mainly to the injured brain at 2 and 4 weeks, and expressed neuronal and glial markers until 6 months. In contrast, non-Muse cells lodged in the lung at 2 weeks, but undetectable by 4 weeks. Magnetic resonance spectroscopy and positron emission tomography demonstrated that Muse cells dampened excitotoxic brain glutamatergic metabolites and suppressed microglial activation. Muse cell-treated group exhibited significant improvements in motor and cognitive functions at 4 weeks and 5 months. Intravenously transplanted Muse cells afforded functional benefits in experimental HIE possibly via regulation of glutamate metabolism and reduction of microglial activation.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
To examine the clinical characteristics of bilirubin encephalopathy in preterm infants (pBE) in Japan.
We performed a two-step nationwide questionnaire survey. The initial survey determined the ...number of children with pBE. Using a structured questionnaire, the second survey clarified the clinical manifestations and characteristics of children with pBE, including the perinatal history, neonatal complications, neurological features, verbal communication, diet, and magnetic resonance imaging (MRI) and auditory brainstem response (ABR) findings.
The initial survey included 190 pBE infants, indicating an incidence of approximately 10 per year. Clinical information was available for 142 of them. The median gestational age was 26 weeks and the median birthweight was 883 g. As to neonatal complications, 20% had none, 25% had one complication, 54% had two or more. Head control was observed in 45% and functional gait in 8%. Purposeful hand use was seen in 41% of patients and verbal communication in 40%. MRI showed T2 hyperintensities in the globi pallidi in 111 of 136 patients, especially between 7 and 18 months of corrected age. ABR abnormalities were present in 88 of 117 patients.
pBE was infrequent but constantly observed during the study period, especially in very preterm infants, even in those with no severe neonatal complications. Severely impaired gross motor function and relatively preserved manual function and verbal communication were characteristic. MRI and ABR abnormalities will facilitate diagnosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The patient was a boy born at 23 weeks and 0 days of gestation weighed 401 g at birth. For treatment, an umbilical venous catheter was placed but the catheter perforated a blood vessel. We thought ...that prompt removal of the catheter would lead to massive bleeding, so we kept the catheter in place at the umbilicus, waited for weight gain, and removed it after confirming that the catheter tip had spontaneously become shallow and was in the umbilical vein. This procedure allowed us to handle the patient without major problems.
Abstract
Fullerenes are compelling molecular materials owing to their exceptional robustness toward multi-electron reduction. Although scientists have attempted to address this feature by ...synthesizing various fragment molecules, the origin of this electron affinity remains unclear. Several structural factors have been suggested, including high symmetry, pyramidalized carbon atoms, and five-membered ring substructures. To elucidate the role of the five-membered ring substructures without the influence of high symmetry and pyramidalized carbon atoms, we herein report the synthesis and electron-accepting properties of oligo(biindenylidene)s, a flattened one-dimensional fragment of fullerene C
60
. Electrochemical studies corroborated that oligo(biindenylidene)s can accept electrons up to equal to the number of five-membered rings in their main chains. Moreover, ultraviolet/visible/near-infrared absorption spectroscopy revealed that oligo(biindenylidene)s exhibit enhanced absorption covering the entire visible region relative to C
60
. These results highlight the significance of the pentagonal substructure for attaining stability toward multi-electron reduction and provide a strategy for the molecular design of electron-accepting π-conjugated hydrocarbons even without electron-withdrawing groups.
Fetal growth restriction (FGR), followed by postnatal early catch-up growth, is associated with an increased risk of metabolic dysfunction, including type 2 diabetes in humans. This study aims to ...determine the effects of FGR and early catch-up growth after birth on the pathogenesis of type 2 diabetes, with particular attention to glucose tolerance, pancreatic islet morphology, and fibrosis, and to elucidate its mechanism using proteomics analysis. The FGR rat model was made by inducing mild intrauterine hypoperfusion using ameroid constrictors (ACs). On day 17 of pregnancy, ACs were affixed to the uterine and ovarian arteries bilaterally, causing a 20.9% reduction in birth weight compared to sham pups. On postnatal day 4 (P4), the pups were assigned to either the good nutrition (GN) groups with 5 pups per dam to ensure postnatal catch-up growth or poor nutrition groups with 15 pups per dam to maintain lower body weight. After weaning, all pups were fed regular chow food ad libitum (P21). Rats in both FGR groups developed glucose intolerance; however, male rats in the FGR good nutrition (FGR-GN) group also developed hypertriglyceridemia and dysmorphic pancreatic islets with fibrosis. A comprehensive and functional analysis of proteins expressed in the pancreas showed that FGR, followed by early catch-up growth, severely aggravated cell adhesion-related protein expression in male offspring. Thus, FGR and early catch-up growth caused pancreatic islet morphological abnormalities and fibrosis associated with the disturbance of cell adhesion-related protein expressions. These changes likely induce glucose intolerance and dyslipidemia in male rats.
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