355 research outputs found
Regulation of dynamic structure of cyclophanes by their complexation with the porphyrin
Dithia[3.3]metacyclophanes which consist of the pyridine unit connecting to the different positions of the parent cyclophane skeleton have been prepared. Conformational change has been observed for the cyclophane having a 4-substituted pyridine unit by binding to the porphyrin. In contrast the porphyrin binding has no influence on conformational behavior of the cyclophane having a 3-substituted pyridine unit
Regulation of dynamic structure of cyclophanes by their complexation with the porphyrin
Dithia[3.3]metacyclophanes which consist of the pyridine unit connecting to the different positions of the parent cyclophane skeleton have been prepared. Conformational change has been observed for the cyclophane having a 4-substituted pyridine unit by binding to the porphyrin. In contrast the porphyrin binding has no influence on conformational behavior of the cyclophane having a 3-substituted pyridine unit
Diagnosis of Occlusal Caries with Dynamic Slicing of 3D Optical Coherence Tomography Images
Detecting the extent of occlusal caries is a clinically important but challenging task required for treatment decision making. The aim of this study was to assess the diagnostic power of 3D swept-source optical coherence tomography (OCT) for evaluation of occlusal caries in comparison with X-ray radiography. Extracted human molars not exhibiting American Dental Association (ADA) criteria advanced caries were mounted in a silicone block and digital dental radiographs were captured from the buccal side. Subsequently, occlusal surfaces were scanned with a prototype Yoshida Dental OCT. Thirteen examiners evaluated the presence and extent of caries on radiographs and dynamically sliced 3D OCT video images, using a 4 level scale-0: intact; 1: enamel demineralization without cavitation; 2: enamel caries with cavitation; 3: dentin caries with or without cavitation. Sensitivity, specificity and area under operating characteristic curves (Az) were statistically analyzed (alpha = 0.05). Reliability analysis showed an excellent agreement among the 13 examiners for both methods. The OCT presented a significantly higher sensitivity and Az value for the detection of caries compared to radiographs (p < 0.05). Radiography showed especially low sensitivity for dentin caries (0-2 versus 3). Dynamic slicing of 3D OCT volumes is a powerful adjunct tool to visual inspection to diagnose the dentin occlusal caries in vitro
Plasma brain natriuretic peptide and the evaluation of volume overload in infants and children with congenital heart disease.
This study was designed to explore whether it was possible to evaluate the severity of VSD, PDA, and ASD by measuring brain natriuretic peptide (BNP) levels. We also investigated normal BNP levels in children to provide a baseline for our study. We measured BNP levels in 253 normal children, including 11 normal neonates, and in 91 VSD patients, 29 PDA patients, and 34 ASD patients. BNP levels showed no age-related differences in normal children (the mean value: 5.3 +/- 3.8 pg/ml). In the healthy neonates, BNP levels rose from 10.4 +/- 11.9 pg/ml in cord blood to 118.8 +/- 83.2 pg/ml on day 0, then fell to 15.3 +/- 7.8 pg/ml by day 7. In VSD and PDA patients, BNP levels correlated significantly with Qp/Qs, LVEDV, and peak RVP/LVP. In ASD patients, BNP levels correlated with Qp/Qs and RVEDV. Especially, in VSD patients, as an index corresponding to 1.5-2.0 of the Qp/Qs ratio, BNP levels of 20-35 pg/ml were found to be best with regard to both sensitivity and specificity. In the healthy neonates, BNP levels changed rapidly after birth. In VSD, PDA, and ASD patients, BNP levels were well-correlated with the severity of the disease. Especially, in VSD patients, it that appears BNP levels may be useful in evaluating surgical indications, with 20-35 pg/ml levels being the appropriate cut-off value.</p
Comparison of the effect of thermal aging on dielectric properties of vegetable oils and impregnated Kraft paper
In this paper, dielectric properties (BDV and permittivity) of two vegetable oils (Palm Fatty Acid Ester and FR3) used in power transformers are studied. Also, partial discharge inception voltage (PDIV) of Kraft paper impregnated with these oils is measured. All the tests were carried out at room temperature and the samples were prepared following the same procedure. Both the impregnated paper and the vegetable oils were aged at 140°C for 11 days to study the evolution of the dielectric properties with the thermal aging. PDIV has been also measured for different number of paper sheets (from 4 to 6), analyzing the dependence of PDIV on the thickness of solid insulation. Dielectric characterization of the oils showed that they are suitable to use in power transformers. BDV of the oils decreased with the aging and PFAE performance was better. Dielectric constant of both oils is almost the same. PDIV results showed that both oils are suitable for the impregnation of Kraft paper in terms of dielectric properties. PDIV of FR3 insulating system was higher than PFAE system in all the studied cases. FR3 insulating systems showed a decrease of PDIV value after the aging process, whereas PFAE one remained almost constant.This research is under BIOTRAFO project, which has received funding from the European Union’s Horizon 2020 Research and Innovation Program under the Marie Sklodowska-Curie Action-Research and Innovation Staff Exchange (MSCA-RISE) grant agreement No 823969. The authors of this research wish to thank the Ministry of Economy for its financial support for the National Research Project: Improvement of Insulation Systems in Transformers Using Dielectric Nanofluids. Thermodynamic Characterization and Modelling (DPI2015-71219-C2 1-R). Also, the authors thank the Council of Universities and Research, Environment and Social Policy for its support for the Project: Impregnation of Dielectric Solids with Biodegradable Fluids Used in Power Transformers 2019-2
Formation of meso, N-diphenylprotoporphyrin IX by an aerobic reaction of phenylhydrazine with oxyhemoglobins.
Administration of phenylhydrazine to rabbits resulted in the denaturation of hemoglobins in erythrocytes, causing the formation of intracellular precipitates known as Heinz bodies, severe hemolytic anemia, and reticulocytosis. To elucidate the molecular mechanism of the destabilization, we allowed human oxyhemoglobins to react aerobically with phenylhydrazine. After treatment with acetic acid/HCl and H2SO4/methanol, the chloroform extract contained blue-green pigments of major products accompanied by different minor products. Each product was isolated by column chromatography. By fast-atom-bombardment mass spectrometry (FAB-MS) and proton nuclear magnetic resonance (1H-NMR) spectrometry, dimethyl esters of N-phenylprotoporphyrin IX and meso, N-diphenylprotoporphyrin IX were determined. Other major products also were determined to be dimethyl esters of triphenyl-and tetraphenyl-substituted protoporphyrins by FAB-MS. The formation of meso, N-diphenylprotoporphyrin indicated that the addition of a phenyl radical to the meso-carbon atom of the protoporphyrin ring occurred. Triphenyl and tetraphenyl adducts also indicated the formation of phenyl radicals in the aerobic reaction of phenylhydrazine with oxyhemoglobins. From these results, we suggest that the formation of phenyl radicals and the replacement of heme with phenyl-substituted protoporphyrins cause the destabilization of hemoglobins to induce Heinz bodies and hemolytic anemia with phenylhydrazine.</p
3D imaging of proximal caries in posterior teeth using optical coherence tomography
Optical coherence tomography (OCT) can create cross-sectional images of tooth without X-ray exposure. This study aimed to investigate the diagnostic accuracy of 3D imaging of OCT for proximal caries in posterior teeth. Thirty-six human molar teeth with 51 proximal surfaces visibly 6 intact, 16 slightly demineralized, and 29 distinct carious changes were mounted to take digital radiographs and 3D OCT images. The sensitivity, specificity and area under the receiver operating characteristic curve (AUC) for the diagnosis of enamel caries and dentin caries were calculated to quantify the diagnostic ability of 3D OCT in comparison with digital radiography. Diagnostic accuracy was evaluated by the agreement with histology using weighted Kappa. OCT showed significantly higher sensitivity, AUC and Kappa values than radiography. OCT can be a safer option for the diagnosis of proximal caries in posterior teeth that can be applied to the patients without X-ray exposure
Recombination Activating Gene (RAG)-1 and 2 Encoding Proteins Expressed by the Baculovirus System
We have been attempting to obtain mouse recombination activating gene-1 (RAG-1) and RAG-2 protein for biochemical analyses. First of all, we obtained truncated products of these genes expressed and purified using the E. coli expression system and then established the polyclonal and monoclonal antibodies by means of E. coli expressed peptides as antigens. Subsequently, whole RAG-1 and RAG-2 gene products were expressed the baculovirus expression system. Since it has been difficult to achieve the significant gene expression of full-lenght cDNA, we employed the glutathione S-transferase (GST)-fused gene-expression system which facilitated the massive expression of gene products. This system was also advantageous in that we could detect the expressed protein molecules not only with anti-RAG antibody but also with anti-GST antibody
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