Hearing loss is a common congenital disorder that is frequently associated with mutations in the Cx26 gene (GJB2). Recently, the mutation analysis of GJB2 has been used in a newborn screening test for the detection of hearing impairment. Population-based studies should be performed before the application of genetic testing for the identification of deaf newborns. In this study, 8 positions of GJB2 mutations-including 35delG, 167delT, 235delC, V27I, V37I, M34T, E114G, and I203T-were analyzed using PCR-direct sequencing in a total of 437 healthy Korean neonates. DNAs from dried blood spots were extracted using a commercial DNA extraction kit. The PCR-amplified products (783 bps) of the GJB2 gene were detected using 2% agarose gel electrophoresis and subjected to direct sequencing. The sequences were compared with those in the GenBank database by using the BLAST program. In this study, 5 GJB2 mutations -including V27I (79G>A), V37I (109G>A), E114G (341A>G), I203T (608T>C), and 235delC- were found. Of the 437 neonate samples, 301 subjects showed GJB2 mutations (68.9%, 301/437). The V27I mutation was found in 271 subjects and was the most frequent (62.0%, 271/437). The E114G, I203T and V37I mutations were shown in 146, 17 and 14 subjects, respectively. The 235delC mutation was found in 1 subject. The E114G mutation was frequently accompanied by the V27I mutation. V27I/E114G (97.2%, 143/147) was the most common double mutation and 3 subjects had the double mutation V27I/I203T. A triple mutation, V27I/E114G/I203T, was found in 1 subject. In conclusion, PCR-direct sequencing is a convenient tool for the rapid detection of GJB2 mutations and this data might provide information for the genetic counseling of the GJB2 gene.
Jin Sang-Keun;Kim Il-Suk;Hur Sun-Jin;Park Ki-Hun;Ha Ji-Hee;Kang Seoc-Mo;Choi Yeung-Joon;Kim Jin-Soo
Food Science of Animal Resources
/
v.26
no.1
/
pp.64-69
/
2006
This study was conducted to determine the effect of pH adjustment on physico-chemical characteristics of chicken breast surimi. The chicken breast meat was ground with distilled water, of which pH was then adjusted to 2.5 (T1), 3.0 (T2), 10.5 (T3) and 11.0 (T4) for surimi manufacture, respectively. Water content was higher in order of T4>T1>T3>T2 (p<0.05). Crude protein and crude fat were higher in T3 and T4 compared with T1 and T2 (p<0.05). $L^*$ values, myofibrillar protein and water holding capacity of T2 and T4 were higher than those of T1 and T3 (p<0.05). T4 had the lowest yield among the treatments (p<0.05). T1 was higher in yield and pH, whereas breaking force and deformation were higher in T1 (p<0.05). $a^*$ was higher in order of T3>T2>T4>T1 and $b^*$ was lower in T1 compared with other treatments (p<0.05). In textural properties, the chewiness values of T2 and T3 were higher than those of T1 and T4, the hardness was higher in order of T2>T3>T4>T1 (p<0.05). Cohesiveness and gumminess of T1 showed higher values than those of other treatments (p<0.05). In sensory evaluation, the note for appearance was higher in T2 than other treatments (p<0.05), however other traits were not significantly different (p>0.05). Therefore, the alkaline processing (T4, pH 11.0) would be recommended.
The prevalence of food allergies was investigated using questionnaires with 300 subjects whose ages ranged from 19 to 24 years old and the causative food allergens was analyzed using immunological analysis with serum of the subjects who answered that they have/had food allergy. The questionnaire showed that 11.33% of subjects have/had experience of food hypersensitivity, where the main causative foods were fish, beef, chicken, milk, egg, and pork in order. The meat allergy shared 4.65% (2.33% for beef, 1.66% for chicken, 0.66% for pork) in the prevalence of food allergies. The causative beef allergens were investigated with the serum of 6 subjects who have had beef allergy. Western blots were carried out with the serum of P6 subject who showed a positive reaction to beef extract in ELISA. The two specific bands were detected in beef extract on the PVDF membrane, and no band was detected in extracts of pork and chicken. A calculation of the distance of migration by SDS-PAGE enabled the molecular masses of the two bands to be estimated as 67kDa and 31kDa, respectively. The 67kDa was revealed as bovine serum albumin (BSA) which is one of the important beef allergens as reported previously though an analysis of the N-terminal amino acid sequence. However we could not identify the sequence of 31kDa, probably because they comprised several subunits and were modified proteins such as glycoprotein that were unlikely to be easily degraded by the Edman method. The 31kDa band were dyed with the PAS (periodic acid-schiff reagent), suggesting that it might be a glycoprotein. These results suggested that the 31kDa might be considered as a novel potential beef allergen which is not reported previously, although further studies are needed.
In order to investigate the compositional change oil composts during the growing of cultivated mushroom (Agaricus bisporus), composts and mushrooms during the period of filling to ending under commercial conditions were subjected to chemical analyses. The results are summarized as follows and the mechanism of composting for mushroom cultivation was proposed. 1) The temperature change of growing bed and room was observed and the yield of mushroom for each cropping time was recorded to get $15.6kg/m^2$ in total crops. 2) Composts after filling showed pH 8.2 which dropped to 6.4 after casing and continued so up to ending. 3) On the dry weight basis of composts, crude ash increased whereas total nitrogen, ether extract and crude fibre decreased gradually to bring about the lowering of organic matter. 4) Total nitrogen of composts decreased gradually and more insoluble nitrogen was lost than soluble nitrogen. The C/N ratio of composts was initially 21 which was gradually lowered to 16. 5) The losses of ${\alpha}-cellulose$, pentosan and lignin in composts were 87%, 75%, and 60%, respectively, in which ${\alpha}-cellulose$ decreased markedly after casing. 6) Free reducing sugars of composts increased continuously. Gradually increased free amino acids till second cropping decreased again thereafter. Composts at the filling stage contained alanine, glutamic acid, glycine and serine in which glycine decreased markedly whereas proline increased remarkably upon mushroom cultivation. 7) Among minerals of composts, phosphorus and zinc tended to decrease, potassium and copper tended to increase anti sodium showed no marked change. 8) In comparison of mushrooms from different cropping time with respect to proximate composition, minerals, free reducing sugars and amino acids, no marked difference was observed. However, a little higher values were observed in crude fat, free reducing sugars and sodium content for early crops and in free amino acids and phosphorus content for late crops. Twelve free amino acids including alanine, serine, threonine, and glutamic acid were detected in the cultivated mushroom. 9) According to above experimental results, it was possible to support the mechanism of compositing that the formation of ammonia and decomposition of carbohydrates by mesophiles are followed by protein biosynthesis, formation of microbial bodies and nitrogen-rich lignin humus complex by thermophiles, thus supplying necessary nutrients for mushroom growth, along with residual carbohydrates.
The status of heavy metal contamination was investigated using chemical analyses of stream waters and sediments obtained from Samsanjeil and Sambong Cu mining area in Goseong-gun, Gyeongsangnam-do. In addition, the degree and the environmental risk of heavy metal contamination in stream sediments was assessed through pollution index (Pl) and danger index (DI) based on total digestion by aqua regia and fractionation of heavy metal contaminants by sequential extraction, respectively. Not only the degree of heavy metal contamination was significantly higher in Samsanjeil area than in Sambong area, but its environmental risk was also revealed much more serious in Samsanjeil area than in Sambong area. The differences in status and level of contamination and environmental risk between both two mining areas may be attributed to existence of contamination source and geology. Acid mine drainage is continuously discharged and flows into the stream in Samsanjeil mining area, and it makes the heavy metal contamination in the stream more deteriorated than in Sambong mining area in which acid mine drainage is not produced. In addition, the geology of Samsanjeil mining area is mainly comprised of andesitic rocks including a small amount of calcite and having lower pH buffering capacity fer acid mine drainage, and it is likely that the heavy metal contamination cannot be naturally attenuated in streams. On the contrary, the main geology of Sambong mining area consists of pyroclastic sedimentary Goseong formation containing a high content of carbonates, particularly calcite, and it seems that these carbonates of high pH buffering capacity prevent the heavy metal contamination from proceeding downstream in stream within that area.
To date, detection of microbial populations in dairy products has been performed using culture media, which is a time-consuming and laborious method. The recently developed chromogenic media could be more rapid and specific than classical culture media. However, the newly developed molecular-based technology can detect microbial populations with greater rapidity and sensitivity than the classical method involving culture media and chromogenic media. This molecular-based technology could provide various options for monitoring the characterization of different states of bacteria and cells. Thus, it could help upgrade the processing system of the dairy industry so as to maintain the safety and quality of dairy foods. Among the various newly developed molecular-based technologies, flow cytometry can potentially be used for monitoring microbiological populations in the dairy industry if official international standards are available for this purpose. When omics technology would have biomarker identification, it could be regarded as the rapid and sensitive analytical methods. Methods based on PCR, which has become a basic technique in microbiological research, can be developed and validated as alternative methods for quantification of dairy microorganisms. This review discusses methods for monitoring microbiological populations in dairy foods and the limitations of these studies, as well as the need for further research on such methods in the dairy industry.
Yang, Eun Young;Chae, Soo-Young;Hong, Jong-Pil;Lee, Hye-Eun;Park, Eun Joon;Moon, Ji-hye;Park, Tae-Sung;Roh, Mi-Young;Kim, Ok Rye;Kim, Sang Gyu;Kim, Dae Young;Lee, Sun Yi;Cho, Myeong Cheoul
Journal of Life Science
/
v.27
no.10
/
pp.1111-1120
/
2017
This study was conducted to select pepper lines that were tolerant to excessive water injury among the pepper germplasm and investigate the genetic characteristics of those lines to contribute to the breeding of pepper cultivars with stable productivity in abnormal weather. Each of the tolerant and susceptible lines went through immersion treatment, and differentially expressed genes between them were analyzed. The tolerant line showed increased expression of the CA02g26670 gene, which is involved in the CONSTANS protein pathway and regulation of flowering by day length, but it exhibited decreased expressions of CA01g21450, CA01g22480, CA01g34470, CA02g00370 and CA02g00380. The susceptible line showed increased gene expressions of CA02g09720, CA02g21290, CA03g16520, CA07g 02110, and CA12g17910, which are involved in the inhibition of proteolytic enzyme activity, DNA binding, inhibition of cell wall-degrading enzyme, and inhibition of nodulin, respectively. Meanwhile the expressions of CA02g02820, CA03g21390, CA06g17700 and CA07g18230 decreased in the susceptible line, in relation to calcium-ion binding, high temperature, synthesis of phosphocholine and cold stress, respectively. The expressions of genes related to apoptosis and peroxidase increased, while that of CA02g16990, which functions as a nucleoside transporter, decreased in both the tolerant and susceptible lines. Based on the different gene expressions between the tolerant and susceptible lines, further studies are needed on breeding abiotic stress-tolerant lines.
Arabis glabra is a localized common rhizomatous flowering plant, This plant is often used in Korean traditional systems of medicine as a remedy for blood cleaning, detoxification, abscess, gastrospasm, arthritis, contraction and diarrhea. Generally drugs that are used for arthritis have antinociceptive and anti-inflammatory properties. However, validity of the anti-inflammatory activity has not been scientifically investigated so far. Therefore, the aim of this study was to investigate the anti-inflammatory potential of A. glabra using the ethanolic extract and its sub-fractions. To evaluate the anti-inflammatory effects, we examined the inflammatory mediators such as nitric oxide (NO) and prostaglandin E2 (PGE2) on RAW 264.7macrophages. Our results indicated that hexane and chloroform fraction significantly inhibited the LPS-induced NO and PGE2 production in the cells. The hexane fraction inhibitory activity for NO tests with IC50 values showed in 21.0 ㎍/㎖. The chloroform fraction inhibitory activity for PGE2 tests with IC50 values showed in 18.0 ㎍/㎖. These efficacy are expected to be able to present the potential for the development of health functional food for the prevention inflammatory diseases because it has sufficient preventive medical possibilities. Further, it is determined that it is necessary to further study the mechanism of cytokine and protein expression associated with inflammation.
Park, Jeong-Eun;Ham, Jun-Sang;Kim, Hey-Kyung;Lee, Chi-Ho;Kim, Dong-Wook;Seol, Kuk-Hwan;Oh, Mi-Hwa;Kim, Dong-Hun;Jang, Ae-Ra
Food Science of Animal Resources
/
v.32
no.2
/
pp.234-240
/
2012
This study was conducted to examine the effects of low molecular weight gelatin hydrolysates (GH, less than 3kDa), extracted from pig skin collagen on the bone metabolism of ovariectomized (OVX) rats. The rats in the experimental groups were randomly segregated into six different treatment groups such as 1) NC, the normal rat fed AIN 93 diet (basal diet) only; 2) OC, the OVX rat fed the basal diet only; 3) GH 0.1, the OVX rat fed the basal diet with 0.1% GH; 4) GH 0.8, the OVX rat fed the basal diet with 0.8% GH; 5) G 0.1, the OVX rat fed the basal diet with 0.1% gelatin; 6) G 0.8, the OVX rat fed the basal diet with 0.8% gelatin. Body weight gain in the GH 0.1, GH 0.8, and G 0.8 was significantly higher than those in the NC and OC. Feed intake of the GH 0.1 and GH 0.8 was higher than that of the NC and OC, while no significant difference was found in feed efficiency ratio (FER). BMD of the GH 0.8 was higher than that of the OC. However, gelatin hydrolysates and gelatin resulted in higher BMC level compare to the OC. Serum HDL-cholesterol of rat fed GH and gelatin was higher than that of OC (p<0.05). LDL-C of the GH 0.1 and the GH 0.8 tended to be less than that of OC. Serum alkaline phosphatase (ALP) of the GH 0.1 was lower than that of the OC. The serum of GH 0.8 showed lower osteocalcin value than the OC (p<0.05). In addition, GOT and GPT levels significantly decreased in all treatment groups. These results indicated that gelatin hydrolysates from pig skin gelatin hydrolysates enhanced BMD and serum biochemical parameters related to bone metabolism. Therefore, the gelatin hydrolysates could be used as a beneficial material to improve bone health.
Park, Choon-Kyu;Kim, Woo-Jun;Kim, Kui-Shik;Park, Jung-Nim
Korean Journal of Food Science and Technology
/
v.28
no.6
/
pp.1135-1141
/
1996
In order to investigate the composition and the actual status of extractive nitrogenous compounds in saeujeot, a salted and fermented seawater shrimp(Acetes japonicus), the extract was analyzed separately into extractive nitrogen, free amino acids, oligpopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds, using specimens collected at fish markets from July in 1994 November in 1995. The extractive nitrogen of saeujeot was ranging from 430 mg to 528 mg, and the total of free amino acids in it was ranging from 1,509 mg to 2,131 mg, The extract was rich in free amino acids especially in lysine, glutamic acid, leucine, arginine, glycine, histidine, and glutamine, However, the content of most free amino acids was fluctuated from collection to collection. The total of nucleotides and related compounds in the extract was ranging from $1.38\;{\mu}mol\;to\;7.41\;{\mu}mol$, and the rage of fluctuation was essential identical with those of the extractive nitrogen and free amino acids. Homarine, trigonelline, ${\beta}-alaninebetaine$, and glycinebetaine were found in the saeujeot extract. Among them, homarine was the most abundant, ranging from 97 mg to 224 mg, but trigonelline, ${\beta}-alaninebetaine$, and glycinebetaine were very low. TMAO and TMA in the saeujeot extract were $13{\sim}80\;mg\;and\;12{\sim}280\;mg$, respectively. A small amount of creatine (less than 6 mg) and creatinine (less than 1 mg) was detected in all samples.
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