• Journal of Environmental Health Sciences
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• v.39 no.1
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• pp.48-55
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• 2013

Objective: The use of nanoparticle products is expected to present a potential harmful effect on consumers. Also, the lack of information regarding inhaled nanoparticles may pose a serious problem. In this study, we addressed this issue by studying pulmonary toxicity after nasal instillation of Al-NPs in SD rats. Methods: The animals were exposed to Al-NPs at 1 mg/kg body weight (low dose), 20 mg/kg body weight (medium dose) and 40 mg/kg body weight (high dose). To determine pulmonary toxicity, bronchoalveolar lavage (ts.AnBAL) fluid analysis and histopathological examination were conducted in rats. In addition, cell viability was investigated at 24 hours after the treatment with Al-NPs. Results: BAL fluid analysis showed that total cells (TC) count and total protein (TP) concentrations increased significantly in all treatment groups, approximately two to three times. Also, lactate dehydrogenase (LDH) and cytokines such as TNF-alpha and IL-6 dose-dependently increased following nasal instillation of Al-NPs. However, polymorphonuclear leukocytes (PMNs) levels showed no significant changes in a dose dependant manner in BAL fluid. In the cytotoxicity analysis, the treatment of Al-NPs significantly and dose-dependently induced cell viability loss (20 to 30%) and damage of cell membrane (5 to 10%) in rat normal lung epithelial cells (L2). Conclusions: Our results suggest that inhaled Al-NPs in the lungs may be removed quickly by alveolar macrophages with minimal inflammatory reaction, but Al-NPs have the potential to affect lung permeability. Therefore, extensive toxicity evaluations of Al-NPs are required prior to their practical application as consumer products.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.16 no.4
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• pp.273-278
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• 2013

We present a case of a 7-year-old boy who had cholestasis after trimethoprim-sulfamethoxazole combination therapy. Liver biopsy was performed 36 days after the onset of jaundice because of no evidence of improving cholestasis. Liver histology revealed portal inflammation, bile plug, and biliary stasis around the central vein with the loss of the interlobular bile ducts. Immunohistochemical stains for cytokeratin 7 and 19 were negative. These findings were consistent with those of vanishing bile duct syndrome (VBDS). Chlestasis was progressively improved with dose increment of urosodeoxycholic acid from conventional to high dose. This is the first case report of trimethoprime-sulfamethoxazole associated VBDS in Korean children. The case suggests that differential diagnosis of VBDS should be considered in case of progressive cholestatic hepatitis with elevation of alkaline phosphatase and gamma-glutamyl transpeptidase after or during taking medicine to treat nonhepatobiliary diseases illness.

• Biomolecules & Therapeutics
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• v.3 no.1
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• pp.38-46
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• 1995

DA-125, a new anthracycline antitumor antibiotic, was administered at dose levels of 0, 0.04, 0.2 and 1.0 mg/kg/day intravenously to pregnant and subsequently delivered Sprague-Dawley rats from day 17 of gestation to day 21 of lactation. Effects of test agent on general toxicity of dams and growth, behaviour and mating performance of F1 offspring were examined. At 1 mg/kg, one out of the twentytwo dams showed difficult delivery, characterized by a stillbirth. Reduction in body weight, loss in food intake, and decrease in spleen weight were also observed in dams. In addition, the lower rates of successful performances in memory test (28.6%) and necrosis of tail end (9.5%) were seen in F1 offspring. At 0.04 and 0.2 mg/kg, no toxic effect on dams and F1 offspring was observed. There were no malformed Fl and F2 fetuses in all groups. The results indicate that the no effect dose levels(NOELs) of DA-125 are 0.2 mg/kg/day for dams and Fl offspring, and over 1 mg/kg/day for F2 fetuses.

• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.47-52
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• 1997

Metastable pseudomorphic GeSi layers grown by vapor phase epitaxy on Si(100) substrates were implanted at room temperature. The implantations were performed with 90 KeV As ions to a dose of $1\times 10^{13}\;\textrm{cm}^2$ for $Ge_{0.08}Si_{0.92}$ layers and 709 keV $BF_2^+$ ions to a dose of $3\times 10^{13}\;\textrm{cm}^2$ for $Ge_{0.06}Si_{0.94}$layers. The samples were subsequently annealed for short 10-40 s durations in a lamp furnace with a nitrogen ambient or for a long 30 min period in a vacuum tube furnace. For $Ge_{0.08}Si_{0.92}$samples annealed for a 30 min-longt duration at $700^{\circ}C$ the dopant activation can only reach 50% without introducing significant strain relaxaion whereas samples annealed for short 40s periods (at $850^{\circ}C$) can achieve more than 90% activation without a loss of strain, For $Ge_{0.06}Si_{0.94}$samples annealed for either 40s or 30min at $800^{\circ}C$ full electrical activation of the boron is exhibited in the GeSi epilayer without losing their strain. However when annealed at $900^{\circ}C$ the strain in both implanted and unimplanted layers is partly relaxed after 30min whereas it is not visibly relaxed after 40s.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.5
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• pp.565-572
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• 1998

The present study was to evaluate the protective effects of bromocriptine, which is known as $D_2$ dopamine receptor agonist and used for the treatment of patients with Parkinson's disease (PD), on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in vitro and in vivo. Lipid peroxidation product (malondialdehyde; MDA) produced by the administration of 6-OHDA was profoundly reduced following the treatment of bromocriptine in a dose-dependent manner in rabbit brain homogenate. Quinone formation by 6-OHDA autoxidation was also attenuated, and its effect was as potent as other antioxidants. Pretreatment of bromocriptine reduced the cytotoxicity of 6-OHDA on SH-SY5Y neuroblastoma cell lines dose-dependently. The loss of striatal dopamine and its metabolite, DOPAC (dihydroxyphenylacetic acid) as well as increase of MDA production caused by intrastriatal injection of 6-OHDA was significantly recovered following the treatment of bromocriptine. The present study clearly showed that bromocriptine had a protective action against 6-OHDA-induced neurotoxicity. These results suggest that bromocriptine has the antioxidant properties, which could be another advantage for delaying the progress of Parkinson's disease.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.18 no.1
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• pp.137-147
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• 1988

This study was designed to investigate the effects of irradiation on the salivary ductal cells, especially on the intercalated ductal cells of the rat parotid glands. For this study, 36 Sprague-Dawley strain rats were irradiated on the head and neck region with absorbed dose of 15Gy by Co-60 teletherapy unit, Picker's model 4M60. The conditions irradiated were that field size, SSD, dose rate and depth were 12×5㎝m, 50㎝, 222 Gy/min. and 1㎝. respectively. The experimental animals were sacrificed 1, 2, 3, 6, 12 hours and 1, 3, 7 days after the irradiation and the changes of the irradiated intercalated duct cells of the parotid glands were examined under the light and electron microscope. The results were as follows: 1. Under the light and electron microscope, the nucleus, mitochondria and secretory granules showed severe changes in the early stage after irradiation and the most severe cellular de- generations were observed 2 hours after irradiation, but the repair processes began from 6 hours after irradiation. 2. Under the electron microscope, loss of the nuclear membranes, derrangement of the chromosomes, swelling and destruction of the secretory granules, and widening of the intercellular spaces were observed after irradiation. 3. Under the light microscope, atrophy and irregular proliferation of the ductal cells, cuboidal metaplasia, hyperchromatism, and the construction or obstruction of the lumen were observed after irradiation.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.4
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• pp.329-335
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• 2018

Loss of response to anti-tumor necrosis factor (anti-TNF) agents in the treatment of inflammatory bowel disease (IBD) is a major consideration to maintain sustained response. Reversal of immunogenicity can re-establish response and increase the durability of these agents. Strategies to reverse immunogenicity include dose-intensification and/or the addition of an immunomodulator. However, there is a relative paucity of data on the efficacy of such interventions in pediatric IBD patients. Available reports have not strictly utilized homogenous mobility shift assay, which reports on anti-drug antibodies even in the presence of detectable drug, whereas prior studies have been confounded by the use of drug sensitive assays. We report four pediatric inflammatory bowel disease patients with successful reversal of immunogenicity on an anti-TNF agent using dose intensification and/or addition of an immunomodulator.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.199-201
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• 2002

Cancer therapy using high-energy $^{12}$ C ions is successfully under way at HIMAC, Japan. An alternative beam to $^{12}$ C is $^{11}$ C ions. The merit of $^{11}$ C over $^{12}$ C is its capability for monitoring spatial distribution of the irradiated $^{11}$ C by observing the $\beta$$^{+}$ decay with a good position resolution. One of the several problems to be solved before its use for therapy is the amount of nuclear interaction that deteriorates the dose concentration owing to the Bragg curve. Utilizing the dedicated secondary beam course for R&D studies at HIMAC, we measured the total energy loss of $^{11}$ C ions in a scintillator block that simulates the soft tissue in human bodies. In addition to the total absorption $^{11}$ C peak, non-negligible bump-shaped contribution is observed in the energy spectrum. The origin of the bump contribution can be nuclear interaction of the incident $^{11}$ C ions with hydrogen and carbon atoms. Further studies to reduce the ambiguity in dose distribution are mentioned.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6381-6384
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• 2015

Background: The purpose of this retrospectively study was to examine the effectiveness and tolerability of a radiotherapy technique for the palliation of symptomatic liver metastases. Materials and Methods: Twentyseven patients with liver metastases were enrolled and received targeted whole liver irradiation consisting of mean 1, 8 Gy in five to twelve fractions to a total mean dose 17Gy. Symptoms at baseline were hepatic pain (26 patients), lost of weight (6), lack of appetite (2), and night sweats (1). Seventeen patients (63%) had failed previous treatment with chemotherapy and/or high-dose steroids. Results: Individual symptom response rates were 100% at 4 weeks. Partial or complete global symptomatic responses were noted in 11 patients (40%) after 2 months. After 3 months, 8 patients (28%) reported loss of pain. The treatment was well tolerated with one patient (3%) experiencing grade 3 toxicity (one vomiting and one diarrhoea). Overall the median survival time was 4.9 months (range 1 - 14 months). One year survival was 39%. Conclusions: This is simple and well-tolerated treatment but to achieve good palliation effects we should carefully selected patients whose conventional treatment does not bring good analgesic control.

• Natural Product Sciences
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• v.13 no.1
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• pp.78-84
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• 2007

Schizandra chinensis fruits (SC) have been used as a traditional Oriental medicine for treatments of many stress-induced diseases. In the present study, we investigated the protective effect of SC aqueous extract(SC-Ex) in the inflammatory diseases of intestine using a mouse model of ulcerative colitis. An experimental colitis was induced by daily treatment with 5% dextran sulfate sodium (DSS). SC-Ex was orally administered from day 2 of DSS treatment in a dose-dependent manner. Administration of SC-Ex reduced significantly clinic signs of DSS-induced colitis, including body weight loss, shorten colon length, increased disease activity index, and histological colon injury. Moreover, SC-Ex suppressed significantly not only the activities of myeloperoxidase (MPO) and chymase, but also the expressions of $TNF-{\acute{a}}$ and COX-2 in DSS-treated colon tissues. Inhibitory effect of SC-Ex was effective at a dose over 20 mg/kg. Our results indicate that SC-Ex may possess therapeutic effect on the development of DSS-induced colitis.