Visible‐light‐induced decarboxylative and deboronative radical addition of aliphatic carboxylic acids and arylboronic acid pinacol esters to electron‐deficient alkenes using two‐molecule organic ...photoredox catalysts, such as dibenzog,pchrysene as an electron donor and 1,4‐dicyanobenzene as an electron acceptor, proceeded efficiently to furnish radical adducts via the generation of alkyl and aryl radicals. The base and substrate play important roles in this photochemical system, and the sequential photoinduced decarboxylation of glutamic acid having two different carboxy groups was successful.
Visible‐light‐induced decarboxylative and deboronative radical addition of aliphatic carboxylic acids and arylboronic acid pinacol esters to electron‐deficient alkenes using two‐molecule organic photoredox catalysts, such as dibenzog,pchrysene and 1,4‐dicyanobenzene, proceeded efficiently to furnish radical adducts via the generation of alkyl and aryl radicals.
Visible‐light‐induced decarboxylative and deboronative radical addition of aliphatic carboxylic acids and arylboronic acid pinacol esters to electron‐deficient alkenes using two‐molecule organic ...photoredox catalysts, such as dibenzog,pchrysene as an electron donor and 1,4‐dicyanobenzene as an electron acceptor, proceeded efficiently to furnish radical adducts via the generation of alkyl and aryl radicals. The base and substrate play important roles in this photochemical system, and the sequential photoinduced decarboxylation of glutamic acid having two different carboxy groups was successful.
Paraganglioma (PGL), an extra-adrenal pheochromocytoma, is a rare tumor, especially in children. While hypersecretion of catecholamines causes the classic triad of headaches, palpitations, and ...profuse sweating, prompt diagnosis is still challenging.
For 7 months, an 8-year-old boy complained of polyuria and weight loss, followed by proteinuria and headache for 1 month prior to admission. He was admitted to our hospital due to an afebrile seizure.
His blood pressure remained markedly elevated even after cessation of the convulsion. Magnetic resonance imaging of the brain revealed posterior reversible encephalopathy syndrome. Abdominal computed tomography showed a mass lesion encasing the left renal artery, measuring 41 mm in length along its major axis. The plasma and urine levels of normetanephrine were elevated. Additionally, iodine-123-metaiodobenzylguanidine scintigraphy showed an abnormal uptake in the abdominal mass with no evidence of metastasis. Based on these findings, we tentatively diagnosed him with PGL.
Substantial alpha- and beta-blocking procedures were performed, followed by a tumor resection and an extended left nephrectomy on day 31 of hospitalization. Pathological findings confirmed the diagnosis of PGL.
The postoperative course was uneventful, and his blood pressure normalized without the use of antihypertensive agents. Genetic testing revealed a known SDHB germline mutation. The same mutation was also detected on his father and paternal grandfather without any history of hypertension or malignant tumor.
It remains challenging to diagnose pheochromocytoma/paraganglioma (PPGL) promptly because PPGL can present with a variety of symptoms. Preceding symptoms of the presented case might be caused by PGL. Although PPGL is a rare disease, especially in children, it should be considered in differential diagnosis when various unexplained symptoms persist.
The role of serum fibroblast growth factor 23 (FGF23) level in early neonatal period on the diagnosis of X-linked hypophosphatemic rickets (XLH) remains unclear.
Two female patients from the first ...pedigree had an affected mother, and the other female from the second pedigree had an affected father. In all three cases, FGF23 levels were high in cord blood and peripheral blood at day 4-5. Additionally, the FGF23 levels considerably increased from birth to day 4-5. We identified a
pathogenic variant and initiated treatment during infancy in each case.
In neonates with a parent diagnosed as
-associated XLH, FGF23 in cord blood and peripheral blood at day 4-5 may be useful markers for predicting the presence of XLH.
Titanium oxide species anchored within the Y-zeolite cavities by an ion-exchange method exhibit a high and unique photocatalytic reactivity for the reduction of CO2 with H2O at 328 K with a high ...selectivity for the formation of CH3OH in the gas phase. The in situ photoluminescence, ESR, diffuse reflectance absorption, and XAFS (XANES and FT-EXAFS) investigations indicate that the titanium oxide species are highly dispersed within the zeolite cavities and exist in a tetrahedral coordination. The charge transfer excited state of the anchored titanium oxide species plays a significant role in the reduction of CO2 with H2O with a high selectivity for the formation of CH3OH, while the catalysts involving the aggregated octahedrally coordinated titanium oxide species show a high selectivity to produce CH4, being similar to reactions on the powdered TiO2 catalysts. The addition of Pt to the anchored titanium oxide catalysts promotes the charge separation which leads to an increase in the CH4 yields in place of CH3OH formation.
Highly dispersed titanium oxide photocatalysts anchored onto transparent plates of porous silica glass were successfully prepared by metal ion implantation, and their photocatalytic reactivity for ...the liquid-phase photocatalytic degradation of an aqueous 2-propanol solution was compared with that in an aqueous TiO2 dispersion. The titanium ions implanted into the porous silica glass are found to be present on the surface layer as isolated tetrahedral titanium oxide moieties by diffuse reflectance absorption, SIMS, XPS, and XAFS analyses. The specific photocatalytic reactivity of the anchored catalyst was much higher than that for TiO2 powder, which may be attributed to the tetrahedrally coordinated titanium oxide moieties. Metal ion implantation is one of the novel and useful techniques to prepare highly efficient photocatalysts on glass plates.
Ultraviolet B radiation (UVB)-induced DNA damage such as cyclobutane pyrimidine dimers (CPDs) and (6-4) photoproducts (6-4PP) in mouse epidermal keratinocytes (Pam212) was suppressed by ...pre-irradiation administration of two autooxidation-resistant vitamin C derivatives, ascorbic acid (Asc)-2-O-phosphate (Asc2P) and dehydro-Asc, but not by Asc or Asc-2-O-α-glucoside (Asc2G). According to Western blot analysis of the UVB-irradiated keratinocytes, expression of the tumor suppressor gene p53 was immediately enhanced from low pre-irradiation levels to the nearly maximum level at 2 h post-irradiation. In contrast, the p53-antagonizing oncogene mdm2 was scarcely expressed at 0-1 h post-irradiation, but was drastically enhanced at 2-3 h post-irradiation, eventually paralleling p53 expression. This suggests that the period for the actual effective function of p53 proteins may be restricted to the initial 0-3 h after UVB irradiation. p53 expression reached the maximum at 3 h post-irradiation and remained unchanged until at least 6 h, reaching its maximum at UVB doses of 20-100 mJ/cm2 - nearly equal to the minimum erythema dose (MED) or to the doubled score for human skin. However, at 200-500 mJ/cm2, p53 expression was markedly suppressed. This suggests a risk for potential photocarcinogenesis at doses greater than double the MED. UVB-induced p53 expression was notably suppressed by Asc2P or dehydro-Asc, but not by Asc. Nuclear expression of the wild-type p53 gene (wt-p53) was markedly promoted at 6 h post-irradiation, and significantly suppressed by Asc, Asc2G or dehydro-Asc, as well as by Asc2P. In contrast, mutation-type p53 (mt-p53), which is known to interfere with wt-p53 function, was not markedly expressed in the nuclei and was explicitly suppressed by Asc2P but not by Asc, dehydro-Asc or Asc2G, which was not cytoprotective against UVB. Thus, compared to non-cytoprotective Asc or the other derivatives, Asc2P suppressed UVB-induced CPD and 6-4PP formation, resulting in both cytoprotective effects and the preferential suppression of mt-p53 over wt-p53.
Using an ionized cluster beam (ICB) method, titanium oxide photocatalysts were prepared on porous Vycor silica glass (PVG) and activated carbon fibers (ACF), and their photocatalytic reactivities for ...the degradation of 2-propanol diluted in water was investigated. Characterizations of these catalysts by means of SEM, XAFS, XRD, XPS and UV–Vis absorption techniques showed that the titanium oxide in transparent thin films could be formed on PVG and titanium oxide clusters could be deposited on the ACF. UV irradiation of these catalysts in a diluted aqueous solution of 2-propanol or 1,2-dichloroethane led to the efficient decomposition of these reactants into CO
2, H
2O and HCl. The titanium oxide catalysts prepared on these porous materials exhibited higher photocatalytic reactivities than TiO
2 powder and titanium oxide catalysts prepared by a conventional impregnation method. The present results have clearly shown that the ICB method is useful in the preparation of titanium oxide photocatalysts combined with porous supports such as PVG and ACF.
The purpose of this research is to provide an underwater glider with high manoeuvrability. This paper deals with the modelling and motion simulation of an experimental vehicle named `ALEX' as a ...test-bed for an underwater glider with independently controllable main wings. ALEX was designed to realise high performance manoeuvrability. The main wings, rudder, elevator, movable balance weight and vent-blow valves can all be controlled by an on-board microcomputer system. The simple cylindrical shape with a NACA0050-shaped nose cone and main wings with the NACA0009 section were found to be suitable for modelling and estimating the hydrodynamic forces. A computational fluid dynamics (CFD) technique was introduced to estimate the hydrodynamic forces acting on the ALEX glider such as lift and drag under various conditions for the angles of incidence for both wings and environmental flow, i.e., the angle of attack. Equations of motion were also formulated for the modelling of ALEX. Motion simulation was conducted to clarify the characteristics of the `underwater glider with independently controllable main wings' in comparison with a conventional `underwater glider with fixed main wings'. Results of the motion simulations were compared with the actual experiments. Several kinds of motion simulations in diving corresponded well with the motions of ALEX actually observed in the experiment tank.
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