• Analytical Science and Technology
• /
• v.14 no.6
• /
• pp.535-539
• /
• 2001

One-dimensional coordination polymer of cadmium(II) complex, $[Cd(SCN)_2(C_4H_6N_2]_n$, has been prepared and characterized by X-ray single crystallography. Structure analysis reveals that each cadmium(II) atom is six-coordinated in distorted octahedral fashion with $CdS_2N_4$ composition. $CdS_2N_4$ composition contains two S and two N atoms from four thiocyanates and tow N atoms from two 4-methylimidazole ligands. Central cadmium(II) atoms are run in parallel to the a-axis and are doubly bridged with neighboring cadmium(II) atoms by the thiocyanate and isothiocyanate ligands. Thus, this complex has a one-dimensional polymer structure in which the 4-methylimidazole is in the trans conformation.

• Natural Product Sciences
• /
• v.13 no.2
• /
• pp.101-104
• /
• 2007

Four isoflavones including tectorigenin (1), irisflorentin (2), irigenin (3), and tectoridin (4) have been isolated from the 70% EtOH extract of Belamcanda chinensis rhizome. The evaluation for protective effect of compounds 1-4 against glutamate-induced cytotoxicity in hippocampal HT22 cell line was conducted. Compound 1 showed significant protective effect with an EC$_{50}$ value of 67.25 ${\pm}$ 1.2 ${\mu}$M, whereas compounds 2-4 were inactive. These results suggest that compound 1 may possess the neuroprotective activity against oxidative cellular injures.

• Bulletin of the Korean Chemical Society
• /
• v.5 no.1
• /
• pp.23-26
• /
• 1984

The crystal structure of phthalylsulfacetamide, one of the long-acting 'sulfa' drugs, has been determined by the X-ray diffraction methods. The crystal is monoclinic with cell dimensions of a = 7.980(3), b = 12.784(2), c = 18.064(7) ${\AA}$ and ${\beta}$= $112.94(2)^{\circ}$, space group $P2_1$/c and Z = 4. The structure was solved by the direct methods and refined to R = 0.048. The sulfonylacetamide moiety is folded with respect to the central phenyl ring and the benzamide and benzoyl planes are nearly perpendicular to each other. This conformation is consistent with those of the relevant molecules containing the corresponding moieties. All of the molecules in the crystal lattice are connected by a three-dimensional hydrogen bonding network.

• Imaging Science in Dentistry
• /
• v.49 no.1
• /
• pp.71-77
• /
• 2019

Primary intraosseous squamous cell carcinoma is a rare malignant central jaw tumor derived from odontogenic epithelial remnants. Predominantly, it affects mandible, although both jaw bones may be involved. This report describes a 60-year-old man who was initially misdiagnosed with a periapical infection related to the right lower wisdom tooth. After four months, the patient presented to a private dental clinic with a massive swelling at the right side of the mandible. Panoramic radiographs and advanced imaging revealed a lesion with complete erosion of the right ramus, which extended to the orbital floor. A biopsy from the mandibular angle revealed large pleomorphic atypical squamous cells, which is the primary microscopic feature of a poorly differentiated squamous cell carcinoma.

• Tribology and Lubricants
• /
• v.39 no.6
• /
• pp.228-234
• /
• 2023

In this study, reciprocating wear tests are performed on AISI 52100 bearing steel to investigate its tribological behavior in a hexagonal boron nitride (h-BN) water solution. The h-BN-based aqueous lubricant is prepared using an atoxic procedure called ultrasonic sonication in pure water. Ball-on-flat reciprocating sliding experiments are conducted, where the ball is slewed on a fixed flat at 50-㎛ displacement. The lubricating behavior of h-BN is compared with that of deionized (DI) water. Results show that the friction coefficient is higher in h-BN testing than that in DI tests, but the results are equalized as the friction coefficient reaches a stable level. Scanning electron microscopic images reveal significant material loss in the center and mild abrasion on the edge of the wear scar in h-BN tests. However, these effects are minor in DI water situations. The results of energy-dispersive X-ray spectroscopy show that considerable oxidation occurs in the central zone of the wear scar in h-BN cases with strong adhesion and material removal. These findings reveal the importance of determining ideal circumstances that can tolerate material friction and wear.

• Journal of the Korean Society of Radiology
• /
• v.82 no.1
• /
• pp.231-236
• /
• 2021

Meningioma is a common neoplasm of the central nervous system; however, primary extracranial meningioma of the paranasal sinus, especially the maxillary sinus, is rare. We report a case of primary extracranial meningioma (fibrous type) of the maxillary sinus and present a literature review of the imaging features that correlate with fibrous meningioma.

• Food Science and Preservation
• /
• v.21 no.5
• /
• pp.747-756
• /
• 2014

The objective of this study was to examine the effects of vitamin C on the formation of aflatoxin $B_1$ ($AFB_1$)-DNA adduct and $AFB_1$-induing cellular oxidative damage in rat livers treated with radiation and $AFB_1$. Six-week-old male Sprague-Dawley rats were randomly divided into five groups: the control group, the $AFB_1$-treated group, the group treated with $AFB_1$ and vitamin C, the group treated with X-ray and $AFB_1$, and the group treated with X-ray and $AFB_1$ with vitamin C. On the first day of the experiment, only one dose of X-rays was exposed to the entire liver at 1,500 cGy. Next, vitamin C was injected at 10 mg/kg body weight via intraperitoneal injection, followed an hour later by the administration of 0.4 mg/kg of $AFB_1$ via intraperitoneal injection. These treatments were administered every three days for 15 days. On the 16th day, the animals were sacrificed. The $AFB_1$ contents of the rat sera were determined via indirect competitive ELISA. In the quantitative analysis of $AFB_1$ in the rat sera via ELISA, $5.17{\pm}0.34ng/mL$ of $AFB_1$ was detected in the $AFB_1$-treated groups, but the amount decreased more significantly to $3.23{\pm}0.76ng/mL$ in the groups treated with $AFB_1$ and vitamin C (p<0.01) than in the $AFB_1$-treated groups. The effect of vitamin C on $AFB_1$-DNA adduct formation was determined via ELISA. The values of $AFB_1$-DNA adduct formation were $9.38{\pm}0.41ng/mL$ in the $AFB_1$-treated groups, but the amount decreased more significantly to $5.28{\pm}0.32ng/mL$ in the groups treated with $AFB_1$ and vitamin C (p<0.01) than in the $AFB_1$-treated groups. Immunohistochemistry revealed that the accumulation of the $AFB_1$ was not observed in the normal liver tissue (G1). The $AFB_1$-positive materials were observed in the central vein and the portal vein of the liver tissue from the $AFB_1$(G2) treatment or the X-ray and $AFB_1$(G4) co-treatment, but the $AFB_1$-positive materials were observed weakly in the group treated with vitamin C (G3 and G5). These results indicate that vitamin C had ameliorating effects on the $AFB_1$ accumulation of liver tissue.

• Journal of radiological science and technology
• /
• v.43 no.3
• /
• pp.155-159
• /
• 2020

The purpose of this study is to investigate the effect of posture changes(Anteroposterior projection, Posteroanterior projection) in the plain abdominal examination on breast dose and to examine its clinical usefulness. This study was used a human body phantom and a glass dosimeter. Glass dosimeters were directly inserted from the center and outside of medial and lateral. In this study, the deep dose was measured in the right breast and the surface dose in the left breast. During the abdominal examination, the central X-ray incident point was perpendicularly incident to the image receptor 5 cm above the iliac crest. The exposure parameters were 82 kVp, 320 mA, 50 ms, x-ray field size 14×17 inch The distance between the center X-ray and the detector was fixed at 110 cm, and only the top two AEC chambers were used. As a result of this study, the medial and lateral side doses of the right breast were 535.73±30.68 μGy and 414.46±33.52 μGy for erect AP, and 145.80±18.52 μGy and 148.76±12.92 μGy in erect PA. The superficial breast dose was 754.00±68.36 μGy on the medial side and 674.06±45.58 μGy on the lateral side in the erect AP, 70.66±7.98 μGy on the medial side, and 86.46±15.35 μGy on the lateral side in the erect PA. There was a statistically significant difference in the difference between the mean values of the medial and lateral side doses in the deep and superficial areas of the breast according to the postural change (p <0.01). As a result of this study, If the abdominal radiography was examined in the PA position, the dose reduction effect was 72.78% on the medial side, 64.10% on the lateral side of the deep breast, 90.62% on the medial side, and 87.17% on the lateral side of the superficial breast compared to the AP position.

• Journal of the Korean Society of Radiology
• /
• v.10 no.3
• /
• pp.215-222
• /
• 2016

X-ray mammography is the most effective method for the diagnosis of calcified lesions of various breast diseases. To reduce patient dose and to obtain optimal image required for diagnosis, the performance of the mammography system should be maintained continuously. Because the target (anode) angle of the X-ray tube is measured from the central X-ray, the effective angle can be slightly different in view of the position on the detector, which can result in degrading spatial resolution of the imaging within the field of view. In this study, we measured the MTF to examine spatial resolution for positions on the detector in the digital mammography system. For a tungsten wire of $50{\mu}m$ diameter, the highest spatial frequency was obtained. It meant that a wire diameter for measuring MTF through LSF should be small compared to the pixel size of the detector used in the mammography system. The spatial resolution showed slightly different performance according to positions on the detector. The center position gave the best spatial resolution and positions away from the center showed the degraded performance although the difference of the spatial resolution was small. The effective focal spot size of the full width at half maximum also showed similar result. It concluded that the slightly increase of the effective focal spot size gave the degradation of the spatial resolution for positions on the detector.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.12
• /
• pp.6385-6390
• /
• 2012

A number of studies have been conducted to explore the association of XRCC1 polymorphisms with thyroid cancer risk, but the results have been inconsistent. Thus we performed the present meta-analysis to clarify this issue based on all of the evidence available to date. Relevant studies were retrieved by searching PubMed and statistical analysis conducted using Stata software. Nine studies were included in this meta-analysis (1,620 cases and 3,557 controls). There were 6 studies (932 cases and 2,270 controls) of the Arg194Trp polymorphism, 7 studies (1432 cases and 3356 controls) of the Arg280His polymorphism and 9 studies (1,620 cases and 3,557 controls) for the Arg399Gln polymorphism. No association of XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphism with thyroid cancer risk was observed in the overall analysis. However, subgroup analysis revealed: 1) an elevated risk in aa vs AA analysis (OR=2.03, 95%CI= 1.24-3.31) and recessive genetic model analysis (OR=1.93, 95%CI= 1.20-3.08) in the larger sample size trials for XRCC1 Arg194Trp polymorphism; 2) a decreased thyroid cancer risk on subgroup analysis based on ethnicity in Aa vs AA analysis (OR=0.84, 95%CI= 0.72-0.98) and in a dominant genetic model (OR=0.84, 95%CI= 0.72-0.97) in Caucasian populations for the XRCC1 Arg399Gln polymorphism; 3) a decreased thyroid cancer risk on subgroup analysis based on design type in Aa vs AA analysis (OR=0.72, 95% CI= 0.54-0.97) among the PCC trials for the Arg399Gln polymorphism. Our results suggest that the XRCC1 Arg399Gln polymorphism may be associated with decreased thyroid cancer risk among Caucasians and XRCC1 Arg194Trp may be associated with a tendency for increased thyroid cancer risk in the two larger sample size trials.