• Reproductive and Developmental Biology
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• 제38권3호
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• pp.107-114
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• 2014

Oral exposure of humans by excess amounts of arsenic may cause disturbances of the reproductive system. In the present study, such exposure was modelled in rats, with the support of sperm principal parameters and histopathological observations. Male Sprague-Dawley rats were randomly divided into three groups where the group I was served as a normal control, group II was received sodium meta-arsenite as arsenic (10 mg/kg b.w/day) and a combination of sodium meta-arsenite and sodium selenite (3 mg/kg b.w/day) in group III. After 6 weeks, there was no significant change in testis weight and in total motility of all the three experimental groups, whereas, rapid moving spermatozoa, moderately moving spermatozoa and slow moving spermatozoa were significantly decreased in arsenic treated rats as compared to control rats. The other sperm principal parameters like progressiveness, average path velocity, straightness linear velocity (VSL), curvilinear velocity (VCL), straightness, linearity sperm head elongation ratio, area, linearity amplitude of lateral head department (ALH) and beat cross frequency (BCF) were found to be reduced in arsenic intoxicated rats. These results are not correlated with the histological studies. On oral administration of selenium ameliorated the adverse effects of arsenic as compared to arsenic alone treated rats. Our findings clearly demonstrate that administration of selenium could prevent some of the deleterious effects of arsenic in the testis.

• Clinical and Experimental Pediatrics
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• 제53권8호
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• pp.805-808
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• 2010

Although sodium nitroprusside (SNP) is often used in pediatric intensive care units, cyanide toxicity can occur after SNP treatment. To treat SNP-induced cyanide poisoning, antidotes such as amyl nitrite, sodium nitrite, sodium thiosulfate, and hydroxycobalamin should be administered immediately after diagnosis. Here, we report the first case of a very young infant whose SNP-induced cyanide poisoning was successfully treated by exchange transfusion. The success of this alternative method may be related to the fact that exchange transfusion not only removes the cyanide from the blood but also activates detoxification systems by supplying sulfur-rich plasma. Moreover, exchange transfusion replaces cyanide-contaminated erythrocytes with fresh erythrocytes, thereby improving the blood's oxygen carrying capacity more rapidly than antidote therapy. Therefore, we believe that exchange transfusion might be an effective therapeutic modality for critical cases of cyanide poisoning.

• Environmental Engineering Research
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• 제21권2호
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• pp.188-195
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• 2016

$17{\alpha}$-Ethynylestradiol (EE2) has gotten growing concerns due to its widely detected in the environment and high estrogenic potency. However, the knowledge on the photochemical behaviors of EE2 in natural waters is still limited. Herein, the photodegradation and estrogenic potency variation of EE2 induced by nitrate were studied using a sunlight simulator consisted by a 300 W medium pressure mercury lamp and 290 nm cut-off filters. It was found that EE2 could be photodegraded at a rate of $0.0193h^{-1}$ in pure aqueous solutions, and the photodegradation of EE2 could be significantly promoted by nitrate. The photodegradation removal rate of EE2 was increased from 9% in Milli-Q water to 85% in 2.0 mM nitrate solutions. Reactive species scavenging experiments demonstrated that the photogenerated $HO{\bullet}$ contributed about 55% to EE2 degradation. Fe(III), Cl- and dissolved humic acid (DHA) could inhibit the photodegradation of EE2 by competing the incident light and photogenerated $HO{\bullet}$, while $HCO_3{^-}$ had no influence on EE2 photodegradation. EE2 was determined to be phototransformed into organic chemicals without estrogenic potency by GC-MS and MCF-7 cell proliferation toxicity tests. These findings could extend our knowledge on the photochemical behaviors of steroid estrogens and provide information for ecological risk assessment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권1호
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• pp.1-6
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• 2009

DNA double-strand breaks (DSBs) occur commonly in the all living and in cycling cells. They constitute one of the most severe form of DNA damage, because they affect both strand of DNA. DSBs result in cell death or a genetic alterations including deletion, loss of heterozygosity, translocation, and chromosome loss. DSBs arise from endogenous sources like metabolic products and reactive oxygen, and also exogenous factors like ionizing radiation. Defective DNA DSBs can lead to toxicity and large scale sequence rearrangement that can cause cancer and promote premature aging. There are two major pathways for their repair: homologous recombination(HR) and non-homologous end-joining(NHEJ). The HR pathway is a known "error-free" repair mechanism, in which a homologous sister chromatid serves as a template. NHEJ, on the other hand, is a "error-prone" pathway, in which the two termini of the broken DNA molecule are used to form compatible ends that are directly ligated. This review aims to provide a fundamental understanding of how HR and NHEJ pathways operate, cause genome instability, and what kind of genes during the pathways are associated with head and neck cancer.

• Journal of Plant Biotechnology
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• 제1권1호
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• pp.61-68
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• 1999

Rapid accumulation of reactive oxygen species (ROS) and their toxic reaction products with lipids and proteins significantly contributes to the damage of crop plants under biotic and abiotic stresses. We have identified several stress activated alfalfa genes, including the gene of the alfalfa ferritin and a novel NADPH-dependent aldose/aldehyde reductase enzyme. Transgenic tobacco plants that synthesize alfalfa ferritin in vegetative tissues-either in its processed form in chloroplast or in the cytoplasmic non-processed form-retained photosynthetic function upon free radical toxicity generated by paraquat treatment and exhibited tolerance to necrotic damage caused by viral and fungal infections. We propose that by sequestering intracellular iron involved in generation of the very reactive hydroxyl radicals through a Fenton reaction, ferritin protects plant cells from oxidative damage. Our preliminary results with the other stress-inducable alfalfa gene (a NADPH-dependent aldo-keto reductase) indicate, that the encoded enzyme may play role in the stress response of the plant cells. These studies reveal new pathways in plants that can contribute to the increased stress resistance with a potential use in crop improvement.

• 대한한방내과학회지
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• 제29권3호
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• pp.703-715
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• 2008

This experiments was performed to determine the effects of Gangzitongmaekeum(降脂通脈飮 : GTE) on antioxidation activity and hyperlipidemia induced by hypercholesterolemic diet in mice. The results obtained were as follows : 1. GTE showed a safety in cytotoxicity and toxicity of human fibroblast cells and liver. 2. GTE showed DPPH scavenging activity, superoxide dismutase (SOD)-like activity and inhibitory effect on reactive oxygen species (ROS). 3. GTE treated mice showed body and liver weight decrease, compared to the hyperlipidemia-induced control group. 4. GTE decreased total cholesterol and LDL cholesterol levels significantly, but HDL cholesterol levels not significantly. 5. GTE decreased triglyceride levels significantly. 6. Glucose levels in GTE treated mice significantly decreased compared to the hyperlipidemia-induced control group. 7. Albumin levels in GTE treated mice were similar with the hyperlipidemia-induced control group. 8. The lipophagy in liver compared with the control group tended to be decreased in GTE treated mice. In the change of aorta, the cell was regular and boundary of vessel wall was clear, compared to the hyperlipidemia-induced control group. 9. TBARS levels in GTE treated mice significantly decreased compared to the hyperlipidemia-induced control group. 10. The change of SOD and catalase activity significantly increased compared to the hyperlipidemia-induced control group. 11. ACAT mRNA level and HMG-CoA reductase mRNA levels in GTE treated mice significantly decreased compared to the hyperlipidemia-induced control group. Conclusion : These results suggest that Gangzitongmaekeum is effective in antioxidation activity and dietary hyperlipidemia-induced mice.

• 한국세라믹학회지
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• 제48권6호
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• pp.537-542
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• 2011

Magnesium hydroxide as a non-halogen flame retardant has increasing attention due to its non-toxicity, high decomposition temperature and smoke suppressant ability during combustion. For the application of magnesium hydroxide retardant to the textile by soaking and coating method, the prerequisite for the coating is a small particle size, stable dispersion, and adhesion to the textile. The dispersion of $Mg(OH)_2$ particles and stability of the coating was checked by monitoring the change of transmittance and backscattering by varying the types of dispersion agents, binder, solvent, and $Mg(OH)_2$ source, and their compositions in the coating. The $Mg(OH)_2$ dispersion coating was applied to PET(poly(ethylene terephthalate)) non-woven textile. The physical properties are characterized by surface morphology, amount of coating, particle dispersion, and adhesion test. The flame retardant $Mg(OH)_2$ coated textile has been compared by limited oxygen index(LOI) and thermal gravimetry and differential scanning calorimetry(TG-DSC). It was found that phosphorous additive may give synergistic effect on $Mg(OH)_2$ flame retardant coating to make the flame retardant PET non-woven textile.

• 한국세라믹학회지
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• 제46권6호
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• pp.583-586
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• 2009

The Tantalum nitride has attracted wide at attention as issues related to the toxicity of Cd-related materials. But in the titration process of Ta$Cl_5$ solution with $NH_4$OH, $NH_4$Cl, as a by product, was remained in the prepared Tantalum precursor. The tantalum precursor with $NH_4$Cl was nitrided by ammonolysis. The red color tone of $Ta_3N_5$ was reduced by the residual $NH_4$Cl reduce. Therefore, amorphous Tantalum precursor was prepared by filtering process with as hydrous ethanol to remove the $NH_4$Cl. In the case of using Tantalum precursor without $NH_4$Cl, we successfully synthesized the Tantalum nitride with good red color. The value of red color tone was improved from $a^*$=36.8 to $a^*$=53.0. The synthesized powder was characterized by XRD, SEM, the Nitrogen / Oxygen Determinator, TG-DTA, and the CIE $L^*a^*b^*$ colorimeter.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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• pp.5253-5257
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• 2014

Formaldehyde (FA) is an economically important chemical, and has been found to cause various types of toxic damage to the body. Formaldehyde-induced toxic damage involves reactive oxygen species (ROS) that trigger subsequent toxic effects and inflammatory responses, which may increase risk of cancer. Therefore, in the present study, we aimed to investigate the possible toxic mechanism in bone marrow caused by formaldehyde. In accordance with the principle of randomization, the mice were divided into four groups of 6 mice per group. One group was exposed to ambient air and the other three groups were exposed to different concentrations of formaldehyde (20, 40, $80mg/m^3$) for 15 days in the respective inhalation chambers, 2h a day. At the end of the 15-day experimental period, all mice were killed. Bone marrow cells were obtained. Some of those were used for the determination of blood cell numbers, bone marrow karyote numbers, CFU-F, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content; others were used for the determination of mitochondrial membrane potential (MMP), cell cycle and Bcl-2, Bax, CytC protein expression. WBC and PLT numbers in median and high dose groups were obvious reduced, but there was no change on RBC numbers. There was also reduced numbers of bone marrow karyotes and CFU-F in the high dose group. SOD activity was decreased, but MDA content was increased. MMP and Bcl-2 expression were decreased with increasing formaldehyde concentration, while expression of Bax and Cyt C was increased. We also observed change in cell cycling, and found that there was S phase arrest in the high dose group. Our study suggested that a certain concentration of formaldehyde could have toxic effects on the hematopoietic system, with oxidative stress as a critical effect.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5553-5565
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• 2013

Plants play important roles in human life not only as suppliers of oxygen but also as a fundamental resource to sustain the human race on this earthly plane. Plants also play a major role in our nutrition by converting energy from the sun during photosynthesis. In addition, plants have been used extensively in traditional medicine since time immemorial. Information in the biomedical literature has indicated that many natural herbs have been investigated for their efficacy against lethal irradiation. Pharmacological studies by various groups of investigators have shown that natural herbs possess significant radioprotective activity. In view of the immense medicinal importance of natural product based radioprotective agents, this review aims at compiling all currently available information on radioprotective agents from medicinal plants and herbs, especially the evaluation methods and mechanisms of action. In this review we particularly emphasize on ethnomedicinal uses, botany, phytochemistry, mechanisms of action and toxicology. We also describe modern techniques for evaluating herbal samples as radioprotective agents. The usage of herbal remedies for combating lethal irradiation is a green anti-irradiation approach for the betterment of human beings without high cost, side effects and toxicity.