• Environmental Engineering Research
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• v.20 no.2
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• pp.127-132
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• 2015

Perfluorooctane sulfonate (PFOS) and Perfluorooctanoic acid (PFOA) are persistent environmental pollutants, extremely stable, and possibly adversely affect human health. They are widely used in many industries and consumer goods, including sunscreen products. These substances are stable chemicals made of long carbon chains, having both lipid- and water-repellent qualities. The research objectives are (1) to find the most effective method for the preparation of semi-liquid samples by comparing solid phase extraction (SPE) and centrifugation after Pressurized liquid extraction (PLE), and (2) to determine the contamination levels of PFOS and PFOA in waterproof sunscreen samples. All sunscreen samples were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Sunscreen samples were purchased from domestic and international brands sold in Thailand. Special chemical properties were considered for the selection of samples, e.g., those found in waterproof, sweat resistant, water resistant, and non-stick products. Considering the factors of physical properties, e.g., operation time, chemical consumption, and recovery percentage for selecting methods to develop, the centrifugation method using 2 mL of extracted sample with the conditions of 12,000 rpm and $5^{\circ}C$ for 1 hour after PLE was chosen. The highest concentrations of PFOS and PFOA were detected at 0.0671 ng/g and 21.0644 ng/g, respectively. Even though present concentrations are found at ng/g levels, the daily use of sunscreen products is normally several grams. Therefore, a risk assessment of PFOS and PFOA contamination in sunscreen products is an important concern, and more attention needs to be paid to the long-term effects on human health.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.168-174
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• 1994

Effects of filtration and centrifugation on the oxidative stabilities of sesame oils during storage at $70^{\circ}C$ were studied by combination of determining peroxide values and conjugated dienoic acid values of oils and measuring the hexanal formation using headspace gas chromatography. Crude sesame oil from roasted seeds contained more free fatty acids, conjugated dienes, and metals (Fe, Cu, Mg and Zn); on the other hand, higher contents of moisture and ${\gamma}-tocopherol$ were found in the filtered or centrifuged oil. Only filtered oil contained more peroxides than the crude oil in spite of the color advantage of the highest L and b values among three oils. All the oils showed the tendency of increasing in total color difference during storage at $70^{\circ}C$, fatty acid compositions were relatively constant except for decreasing tendency of linoleic acid in filtered oil. No significant difference at 1% in the oxidative stabilities was observed between centrifuged oil and crude oil with higher susceptibility to the oxidation in the filtered oil. Centrifuged sesame oil was the best in the aspect of both oxidative stability and the oil color.

• Journal of Life Science
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• v.8 no.4
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• pp.400-409
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• 1998

Formation of adduct was studied in benzo(a)pyrene(BP)- and doxorubicin(Dx)-treated human NC-37 cells and isolated nuclei. Major adducts formed were determined by fluorescence absorption spectrophotometery and DNA-lin-ked protein assay. When isolated nuclei were exposed to carcinogens BP and DMBA, and anticancer drugs m-AMSA, ellipticine and Dx, varying degrees of adduct formation occured between DNA-protein complex and these drugs. When the mixture was centrifuged 1.7 M sucrose solution, binding BP and DMBA appeared to be similar between the sediment and the supernatant. When the sediment was centrifuged again with 0.35% polymin-P, the amount of BP bound was 2-fold greater in the protein(1077$\pm$55cpm) than in DNA fraction (470$\pm$20cpm), whereas that of DMBA was 1.6-fold greater in the DNA than in protein fraction. In the case of m-AMSA, ellipticine and Dx, the amount of binding was slightly greater in supernatant than in sediment in centrifugation with 1.7 M sucrose, and more than 3 times greater in the DNA- than in protein- fraction in centrifugation with 0.35% polymin P. DNA fractions which associated with a subset of nonhistone chromosomal protein were isolated from NC-37 cells exposed to $^{3}$H-BP and $^{14}$C-Dx. They were separated into two distince components DNA-S and DNA-P by centrifugation with 2M Nacl chromatin extraction. The results indicated that the amount of $^{3}$H-BP bound was 6.0-fold greater in DNA-P as compared with DNA-S, while that of $^{14}$C-Dx binding appreaed to be 6.2-fold greater in DNA-S than in DNA-P fraction. When $^{3}$H-BP binding wasdetermined in the presence of cold Dx, the amount of binding was reduced only in the DNA-P fraction, indicating that the interaction between DNA and protein is decreased. Gene expression by these drugs, BP treated cells were increased to compare with nomal cells but reduced by treatment with BP-Dx. These results suggest that the protein moiety which tightly bound to DNA-P fraction may play an important role in the regulation of gene expression.

• Clinical and Experimental Reproductive Medicine
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• v.42 no.1
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• pp.22-29
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• 2015

Objective: Sperm must be properly prepared in in vitro fertilization (IVF)-embryo transfer (ET) programs in order to control the fertilization rate and ensure that embryos are of high quality and have appropriate developmental abilities. The objective of this study was to determine the most optimal sperm preparation method for IVF. Methods: Patients less than 40 years of age who participated in a fresh IVF-ET cycle from November 2012 to March 2013 were included in this study. Poor responders with less than three mature oocytes were excluded. Ham's F-10 medium or sperm-washing medium (SWM) was used in combination with the density-gradient centrifugation/swim-up (DGC-SUP) or SUP methods for sperm preparation. A total of 429 fresh IVF-ET cycles were grouped according to the media and methods used for sperm preparation and retrospectively analyzed (DGC-SUP/Ham's F-10, n=82; DGC-SUP/SWM, n=43; SUP/Ham's F-10, n=181; SUP/SWM, n=123). Results: There were no significant differences among these four groups with respect to the mean age of the female partners, duration of infertility, number of previous IVF cycles, and retrieved oocytes. We determined that both the DGC-SUP and SUP methods for sperm preparation from whole semen, using either Ham's F-10 or SWM media, result in comparable clinical outcomes, including fertilization and pregnancy rates. Conclusion: We suggest that both media and both methods for sperm preparation can be used for selecting high-quality sperm for assistive reproductive technology programs.

• Food Science and Preservation
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• v.13 no.2
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• pp.138-143
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• 2006

Clarified apple juice was prepared using different clarification methods including centrifugation, ultrafiltration (UF), and combined treatment (CT). Effects of clarification methods as well as other qualify parameters were investigated Clarification was clearly improved with an increase in centrifugation speed and towering temperature. Especially, lowering the temperature led to a decrease in turbidity values at 5,000 rpm. The optimum condition for centrifugation process was $5^{\circ}C$ and 10,000 rpm, respectively. UF and CT were very effective to produce clarified apple juice. The optimum condition of UF process was $45^{\circ}C$ and 150 kPa considering flux and turbidity. L*-values were increased while a*-values were decreased significantly after clarification regardless of methods (P<0.05). Vitamin C was most retained in the clarified samples using CT.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.369-375
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• 1997

Studies were conducted to determine the efficiency of decondensation protocols. Sperm obtained from seven normal donors was immediately washed after liquefaction and then decondensed using the method of West et al. (1989) and my original protocol. My optimized protocol entailed mixing 1 ml aliquots of semen with 4 ml phosphate buffered saline (PBS). Following centrifugation, pellets were resuspended in 1 ml PBS containing 6 mM EDTA. After centrifugation, pellets were resuspended in 1 ml PBS containing 2 mM dithiothreitol at $37^{\circ}C$ for 45 min. Following mixing with 2 ml PBS and centrifugation, pellets were resuspended by vortexing. While vortexing, 5 ml of fixative were gently added. Slide preparation was accomplished using the smear method and it was stored at $4^{\circ}C$. When comparing these protocols, the degree of sperm decondensation and head swelling was monitored by measuring nuclear length, area, perimeter, and degree of roundness using FISH analysis software. Apparent copy number for chromosome 1 and, separately, for the sex chromosomes was determined by FISH using satellite DNA probes for loci DIZ1, DXZ1 and DYZ3. Sperm treated by my decondensation protocol showed significant increases (p<0.05) in length, area, perimeter, and degree of roundness. There was a significant decrease (p<0.05) in the frequency of nuclei displaying no signal but no change in the frequency of nuclei with two signals in samples decondensed by my protocol. My data suggested that decondensation using my original protocol may lower the frequency of cells with spurious "nullisomy" due to hybridization failure without inducing spurious "disomy" resulting from increased distances between split signals.

• Restorative Dentistry and Endodontics
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• v.17 no.1
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• pp.222-234
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• 1992

The purpose of this study was to evaluate the systemic and local production of immunoglobulins and their levels in patients with periapical cysts using Enzyme - Linked Immunosorbent Assay. Streptococcus sanguis, Bacteroides gingivalis, and Bacteroides intermedius were grown for use as antigen and they were harvested by centrifugation. The patients were divided into two groups: patients of periapical cysts and normal control. 5 patients of each group were selected and their blood were obtained via intravenous puncture prior to surgical operation. Sera were prepared by centrifugation of each blood samples. Cyst fluid were aspirated from cystic cavity and cyst wall were excised at operation. Control tissue were also excised at extraction site of impacted wisdom teeth from normal control. Each tissue was prepared by homogenization and centrifugation. Then antibodies of each sample were measured by modified ELISA. The following results were obtained: 1. Serum IgG and IgM levels were not significantly different between patients with periapical cyst and normal control. 2. IgG and IgM levels of cyst fluid to Bacteroides gingivalis and Bacteroides intermedius were significantly higher than those of serum of patients with periapical cyst, but there was no significant difference to Streptococcus sanguis. 3. IgG and IgM levels of cyst wall to Bacteroides gingivalis and Bacteroides intermedius were significantly higher than those of control tissue, but there was no significant difference to Streptococcus sanguis. 4. IgG and IgM levels in cyst fluid and IgG levels in cyst wall were highest to Bacteroides gingivalis, and IgM levels in cyst wall were highest to Bacteroides intermedius.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.153-157
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• 2014

Purpose: SLE (systemic lupus erythematosus) is an inflammatory autoimmune disease, characterized by various autoantibody. The detection of Anti double-stranded DNA (Anti-ds DNA) is important in the diagnostics of SLE, and include the American College of Rheumatology (ACR) diagnostic criteria for SLE. Also SLE disease activity and correlativity with the level Anti-ds DNA antibody have been reported and Anti-ds DNA antibody quantitative test is very useful for tracing before and after SLE treatment. When These Anti-ds DNA antibody test (Farr assay: $^{125}I$ labeled ds-DNA and bound Anti-ds DNA antibodies complex in serum is precipitated by ammonium sulfate and used to centrifugation, measured it) inhaled supernatant after centrifugation, a lipemic specimen does not facilitate the formation of precipitate and also occurs situation was inhaled with precipitate. To solve these problems, The Influence of the degree of lipemic specimen was evaluated. Materials and Methods: September 2012 to February 2013, We selected lipemic samples (n=81) of specimen commissioned by Anti-ds DNA antibody test. Lipemic samples were done pre-treatment (high-speed centrifugation: 14,000 rpm 5 mins) used a micro-centrifuge (Eppendorf Model 5415D). At the same time lipemic specimen and pre-treatment samples were performed Anti-ds DNA antibody test (Anti-ds DNA kit, Trinity Biotech, Ireland). Statistical analysis were analyzed Pearson's correlation coefficients and regression and paired t-test, and Difference (%). Results: Experimental group 1 (Lipemic Specimen Anti-ds DNA Ab concentration ${\leq}7IU/mL$) at y=0.368X+4.732, $R^2=0.023$, Pearson's correlation coefficient was 0.154, paired t-test (P=0.003), Difference (%) mean 65.7 and showed a statistically significant difference. Experimental group 2 (Lipemic Specimen Anti-ds DNA Ab concentration ${\geq}8IU/mL$) at y=0.983X+0.298, $R^2=0.994$, Pearson's correlation coefficient showed 0.997, paired t-test (P=0.181), Difference (%) mean -5.53 made no statistically significant difference. Conclusion: Lipemic sample of low Anti-ds DNA Ab concentration (2.5-7 IU/mL) and the result is obtained pre-treatment (high-speed centrifugation: 14,000 rpm 5 mins) were made a significant difference statistically. Anti-ds DNA is one of the primary auto-antibodies present in patients with SLE, and remain an important diagnostic test for SLE. Therefore, we recommend preprocessing (high-speed centrifugation: 14,000 rpm 5 mins) in order to exclude the influence of lipemic specimen.

• Journal of Life Science
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• v.19 no.6
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• pp.728-734
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• 2009

In this work, a simple, inexpensive and reproducible technique of flotation density gradient centrifugation was developed to isolate monocytes with high purity and yield from peripheral blood mononuclear cells (PBMC) using Histopaque solution, density and osmolarity of which were modified to 1.072 g/ml and 335 mOsm with phosphate-buffered saline (PBS) and sodium chloride (NaCl) solution, respectively. The average purity of monocytes was 74.75${\pm}$3.84%, with the individual purity ranging from 71.44% to 82.38%. The average yield of monocytes was 32.62${\pm}$11.16%, with the individual yields ranging from 21.02 to 53.63%. The monocytes isolated by floatation density gradient centrifugation could be successfully cultured into morphologically, phenotypically and functionally dendritic cells in vitro. In conclusion, the entire procedure seemed to be faster and more convenient, simple and cost-effective than other monocyte isolation methods, including plastic adherence and density gradient methods, and has the potential to be developed as a closed system for clinical scale generation of dendritic cells.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.321-328
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• 2004

Raw mulberry (Morus spp.) juice was prepared by minimal processing using several filter aids, fining agents, and clarifying enzymes, followed by filtration, centrifugation, and membrane filtration. Control of browning in minimally processed mulberry juices by anti-browning agents, sodium hydrosulfite, L-ascorbic acid, citric acid, and NaCl, was investigated using quantitative measurements of color changes during storage. Clarification of mulberry juice was improved by adding several filter aids, fining agents, and enzymes, followed by filtration and centrifugation. Several fining agents, including chitosan, chitin, PVPP, gelatin, and casein at a concentration of 1%, and combination of ultrafiltration and centrifugation at 8,000 rpm were not suitable for clarification of juice owing to strong adsorption of anthocyanin pigment. Combination of $0.01\;{\mu}m$ membrane filtration and centrifugation at 8,000 rpm was effective for clarification of mulberry juice. Browning of minimally processed mulberry juice was inhibited significantly by adding 200 ppm sodium hydrosulfite, and 0.1% L-ascorbic acid (L-AsA) and 0,1% citric acid (CA) also showed considerable browning inhibition. Combination of L-AsA and CA, which was moderately effective for browning inhibition of juice, may be useful as a sulfite alternative for mulberry juice. Optimum sugar ($^{\circ}Brix$)/acid ratio and commercial sterilization of minimally processed mulberry juice were approximately 40 and 10 min at $85-90^{\circ}C$, respectively.