• Title/Summary/Keyword: pH-sensitivity

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pH-Dependence of RNA Extraction for Norovirus by TRIzol Method (TRIzol을 이용한 노로바이러스 RNA 추출의 pH 의존성)

  • Jhon, Deok-Young
    • Journal of Food Hygiene and Safety
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    • v.33 no.1
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    • pp.71-76
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    • 2018
  • Norovirus is a leading cause of sporadic pathogenic non-bacterial gastroenteritis worldwide. For the detection of norovirus, reverse transcription real-time PCR (RT qPCR) has quickly become a major tool due to its sensitivity and specificity. However, accurate viral RNA extraction methods are essential for RT qPCR analysis. TRIzol reagents are used to extract RNA from biological materials and are therefore widely used for norovirus RNA extraction. In this study, the yield of viral RNA extraction using TRIzol from genogroup II (GII) among the human norovirus genogroup I (GI) and GII, and murine norovirus (GV) depended on the pH of the virus sample solution. The yield of RNA extraction was higher at the alkaline pH than in the acidic region compared with the Ct (threshold cycle) value of the real-time PCR. From the results of this study, it was found that the pH condition is very important for the quantitative analysis of norovirus by extracting GII RNA using TRIzol.

Silk Dyeing Method in Natural Pigments - In Case of Korean Colored Rice Bran - (한국산 유색미 속겨의 안토시아닌 색소에 의한 견직물염색)

  • 이혜자;유혜자;김정희;이전숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.2
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    • pp.263-269
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    • 2002
  • This research was conducted to establish the efficient use of the colored rice bran fur dyeing textiles. To investigate the fabric dyeability of the colored rice bran extract, the anthocyanin pigments were extracted with water of different temperature ranges of 40 ~ 8$0^{\circ}C$ and were dyed on silk fabrics with different dyeing temperature $25^{\circ}C$~6$0^{\circ}C$, at acidic pH and neutral pH, respectively. Aluminum chloride was preheated with mordant K/S value and dyeing fastness of dyed silk fabrics were examined. The anthocyanins of the colored rice bran were stable and red color at acidic pH, red purple or purple blue at neutral pH, but unstable, blue color at alkaline pH. If extracting temperature and dyeing temperature of dyeing solution were higher, the dyeability was high, but the color of dyed fabric showed red tone. When extracting temperature was 8$0^{\circ}C$ and dyeing temperature of dyeing solution was 6$0^{\circ}C$, the dyeability was best. Without mordant, the dyeability of silk fabrics was higher in acidic pH than in neutral pH solution. With mordant, the dyeability was higher than without mordant, and also higher in acidic pH. Pretreatment of aluminum chloride resulted in the increase of color intensity and stability. The laundering fastness of dyed fabrics was good from grade 5 to grade 3-4. Because of the anthocyanins sensitivity on light radiation, the light fastness of dyed fabrics was poor from grade 3 to grade 1-2.

Modified Carrageenan. 6. Crosslinked Graft Copolymer of Methacrylic Acid and kappa-Carrageenan as a Novel Superabsorbent Hydrogel with Low Salt- and High pH-Sensitivity

  • Pourjavadi A.;Harzandi A. M.;Hosseinzadeh H.
    • Macromolecular Research
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    • v.13 no.6
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    • pp.483-490
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    • 2005
  • A novel, polysaccharide-based, superabsorbent hydrogel was synthesized through crosslinking graft copolymerization of methacrylic acid (MAA) onto kappa-carrageenan ($_{k}C$), using ammonium persulfate (APS) as a free radical initiator in the presence of methylenebisacrylamide (MBA) as a crosslinker. A proposed mechanism for $_{k}C$­g-polymethacrylic acid ($_{k}C$-g-PMAA) formation was suggested and the hydrogel structure was confirmed using FTIR spectroscopy. The effect of grafting variables, including MBA, MAA, and APS concentration, was systematically optimized to achieve a hydrogel with the maximum possible swelling capacity. The swelling kinetics in distilled water and various salt solutions were preliminarily investigated. Absorbency in aqueous salt solutions of lithium chloride, sodium chloride, potassium chloride, calcium chloride, and aluminum chloride indicated that the swelling capacity decreased with increased ionic strength of the swelling medium. This behavior can be attributed to the charge screening effect for monovalent cations, as well as ionic crosslinking for multivalent cations. The swelling of super absorbing hydrogels was measured in solutions with pH ranging from 1 to 13. In addition, the pH reversibility and on-off switching behavior, at pH levels of 3.0 and 8.0, give the synthesized hydrogels great potential as an excellent candidate for the controlled delivery of bioactive agents.

Development and Evaluation of Non-Hydrous Skin Analogue Liquid Crystal using Thermo-Sensitivity Smart Sensor

  • Yoo, Kwang-Ho;Hong, Jae-Hwa;Eun, So-Hee;Jeong, Tae-Hwa;Jeong, Kwan-Young
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.3
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    • pp.367-374
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    • 2014
  • In this study, skin permeation enhancement was confirmed by designing it to have a structure and composition similarity to the intercellular lipids that improve miscibility with skin by cross-linked lipids poloxamer. The cross-linked lipids poloxamer was synthesized and analyzed by 1H NMR that structure dose had conjugated pluronic with ceramide3. Active component is released by modification of liquid crystal structure because PPO part, large-scale molecule block of pluronic, has hydrophobic nature at skin temperature of $35^{\circ}C$. Conjugated pluronic with ceramide3 was synthesized using Pluronic F127 and p-NPC (4-nitrophenyl chloroformate) at room temperature yielded 89%. Pluronic(Ceramide 3-conjugated Pluronic) was synthesized by reaction of p-NP-Pluronic with Ceramide3 and DMAP. The yield was 51%. This cross-linked lipids poloxamer was blended and dissolved at isotropic state with skin surface lipids, phospholipid, ceramide, cholesterol and anhydrous additive solvent. Next step was preceded by ${\alpha}$-Transition at low temperature for making the structure of Meso-Phase Lamella, and non-hydrous skin analogue liquid crystal using thermo-sensitivity smart sensor, lamellar liquid crystal structure through aging time. For confirmation of conjugation thermo-sensitivity smart sensor and non-hydrous skin analogue liquid crystal, structural observation and stability test were performed using XRD(Xray Diffraction), DSC(Differential Scanning Calorimetry), PM (Polarized Microscope) And C-SEM (Cryo-Scanning Electron Microscope). Thermo-sensitivity observation by Franz cell revealed that synthesized smart sensor shown skin permeation effect over 75% than normal liquid crystal. Furthermore, normal non-hydrous skin analogue liquid crystal that not applied smart sensor shown similar results below $35^{\circ}C$ of skin temperature, but its effects has increased more than 30% above $35^{\circ}C$.

Acidic Pelvic Drainage as a Predictive Factor For Anastomotic Leakage after Surgery for Patients with Rectal Cancer

  • Yang, Liu;Huang, Xin-En;Xu, Lin;Zhou, Xin;Zhou, Jian-Nong;Yu, Dong-Sheng;Li, Dong-Zheng;Guan, Xin
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.5441-5447
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    • 2013
  • Purpose: To demonstrate the value of sequential determinations of pelvic drainage in the identification of increased risk of anastomotic leakage (AL) after anterior resection for rectal cancer with a double stapling technique. Patients and Methods: Between January 2004 and December 2011, data for the daily postoperative pH of pelvic drainage fluid in 753 consecutive patients with rectal cancer who initially underwent anterior resection with a double stapling technique were reviewed. All patients experienced a total mesorectal excision. Patients with anastomotic leakage (Group AL, n=57) were compared to patients without leakage (Group nAL, n=696). Patients with perioperatively abdominopelvic implants that were likely to affect pH value (determined at $25^{\circ}C$) other than leakage were excluded. Mean postoperative values were compared. Results: Anastomotic leakage was noted in 57 (7.6%) of 753 patients with rectal cancer. The diagnosis of AL was made between the $6^{th}$ and $12^{th}$ postoperative day (POD; mean $8^{th}$ POD). There was no significance of the daily average values of pH on POD1 & 2 in group AL while a significantly sharp declining mean pH value reached its diagnostic point of AL (p<0.001) on POD3. A cut-off value of 6.978 on the $3^{rd}$ POD maximized the sensitivity (98.7.0%) and specificity (94.7%) in assessing the risk of leakage. Conclusion: According to these results, an early and persistent declining of pH value of pelvic drainage fluid after rectal surgery with anastomosis, is a marker of AL. A cut-off value of 6.798 determined at $25^{\circ}C$ on POD3 maximizes sensitivity and specificity.

Comparison of DNase activities from excretory/secretory productsof Haemonchus contortus fenbendazole-resistantand -susceptible isolates (Fenbendazole에 저항성과 감수성을 지닌 염전위충의 분비배설물에서의 DNase 활성 비료)

  • Kwak, Dongmi
    • Korean Journal of Veterinary Research
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    • v.44 no.3
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    • pp.455-462
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    • 2004
  • Change in ${\beta}$-tubulin nucleic acid and protein sequences was the only known difference between Haemonchus contortus fenbendazole (FBZ)-resistant and -susceptible isolates. This change was sufficient to determine the pathologic effect induced by FBZ treatment. This research was initiated to investigate further differences from these two isolates. Since ${\beta}$-tubulin is involved in formation of microtubule, which has functions in secretory vesicle transport, DNase activities from excretory/secretory products (ESP) of the two isolates were compared, based on pH, sensitivity to DNase inhibitors, molecular masses and production of 3'-OH. The most significant difference detected was that a 38.5 kDa DNase activity was identified from ESP of H. contortus FBZ-susceptible isolates but not from those of H. contortus FBZ-resistant isolates. However, it was shown that the 38.5 kDa DNase is expressed with similar level of activity in intestine and whole worm of H. contortus FBZ-resistant and -susceptible isolates. This result demonstrated that the secretory transport pathway of the 38.5 kDa DNase was inhibited by unknown mechanisms, which may be related with ${\beta}$-tubulin sequence change in FBZ-resistant isolates. Other DNases of 34, 36 and 37 kDa were detected from ESP of both H. contortus FBZ-resistant and -susceptible isolates. Overall DNase activities found from ESP of these two isolates were not inhibited by 10 mM EDTA at pH 5.0, but largely inhibited by pH 7.0. In addition, DNase activities in two isolates produced DNA fragments with mixtures of 3'- hydroxyls (OH) and 3'-phosphates (P) at each pH although the 3'-end labeling ratios at pH 5.0 and 7.0 were shown different. Identification of inhibition of the 38.5 kDa DNase secretion in FBZ-resistant isolates suggests existence of further differences, in addition to ${\beta}$-tubulin sequence change, in two isolates. This shows complex effect of FBZ on H. contortus biological mechanisms.

The effect of additive on $SnO_2$ gas sensor for improving stability ($SnO_2$계 가스 센서의 안정성 향상을 위한 산화물의 첨가 효과)

  • Park, Kwang-Mook;Min, Bong-Ki;Choi, Soon-Don;Nam, Hyo-Duk
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.865-868
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    • 2002
  • $SnO_2$ powders were prepare by precipitating $Sn(OH)_4$ from an aqueous solution of $SnCl_4{\cdot}5H_2O$, pH 9.5. The effects of stability and sensitivity of $SnO_2$ thick film sensors added with various amounts, $SiO_2$, $Al_2O_3$, $ZrO_2$, $TiO_2$ have been investigated. It is shown that the 3wt% $Al_2O_3$ or $SiO_2$ can improve the stability of $SnO_2$ gas sensor at an operating temperature of $350^{\circ}C$.

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Monitoring of Bioluminescent Lactobacillus plantarum in a Complex Food Matrix

  • Moon, Gi-Seong;Narbad, Arjan
    • Food Science of Animal Resources
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    • v.37 no.1
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    • pp.147-152
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    • 2017
  • A bioluminescent Lactobacillus plantarum (pLuc2) strain was constructed. The luminescent signal started to increase during the early exponential phase and reached its maximum in the mid-exponential phase in a batch culture of the strain. The signal detection sensitivity of the strain was the highest in PBS (phosphate buffered saline), followed by milk and MRS broth, indicating that the sensitivity was influenced by the matrix effect. The strain was used in millet seed fermentation which has a complex matrix and native lactic acid bacteria (LAB). The luminescent signal was gradually increased until 9 h during fermentation and abolished at 24 h, indicating that the strain could be specifically tracked in the complex matrix and microflora. Therefore, the bioluminescent labeling system can be used for monitoring LAB in food and dairy sciences and industries.

LncRNA MALAT1 Depressed Chemo-Sensitivity of NSCLC Cells through Directly Functioning on miR-197-3p/p120 Catenin Axis

  • Yang, Tian;Li, Hong;Chen, Tianjun;Ren, Hui;Shi, Puyu;Chen, Mingwei
    • Molecules and Cells
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    • v.42 no.3
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    • pp.270-283
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    • 2019
  • This study was aimed to explore if lncRNA MALAT1 would modify chemo-resistance of non-small cell lung cancer (NSCLC) cells by regulating miR-197-3p and p120 catenin (p120-ctn). Within this investigation, we totally recruited 326 lung cancer patients, and purchased 4 NSCLC cell lines of A549, H1299, SPC-A-1 and H460. Moreover, cisplatin, adriamycin, gefitinib and paclitaxel were arranged as chemotherapies, and half maximal inhibitory concentration (IC50) values were calculated to evaluate the chemo-resistance of the cells. Furthermore, mice models of NSCLC were also established to assess the impacts of MALAT1, miR-197-3p and p120-ctn on tumor growth. Our results indicated that MALAT1 and miR-197-3p were both over-expressed within NSCLC tissues and cells, when compared with normal tissues and cells (P < 0.05). The A549, H460, SPC-A-1 and SPC-A-1 displayed maximum resistances to cisplatin ($IC50=15.70{\mu}g/ml$), adriamycin ($IC50=5.58{\mu}g/ml$), gefitinib ($96.82{\mu}mol/L$) and paclitaxel (141.97 nmol/L). Over-expression of MALAT1 and miR-197-3p, or under-expression of p120-ctn were associated with promoted viability and growth of the cancer cells (P < 0.05), and they could significantly strengthen the chemo-resistance of cancer cells (P < 0.05). MALAT1 Wt or p120-ctn Wt co-transfected with miR-197-3p mimic was observed with significantly reduced luciferase activity within NSCLC cells (P < 0.05). Finally, the NSCLC mice models were observed with larger tumor size and weight under circumstances of over-expressed MALAT1 and miR-197-3p, or under-expressed p120-ctn (P < 0.05). In conclusion, MALAT1 could alter chemo-resistance of NSCLC cells by targeting miR-197-3p and regulating p120-ctn expression, which might assist in improvement of chemo-therapies for NSCLC.

Hydrogen and Alkali Ion Sensing Properties of Ion Implanted Silicon Nitride Thin Film

  • Park, Gu-Bum
    • Transactions on Electrical and Electronic Materials
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    • v.9 no.6
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    • pp.231-236
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    • 2008
  • B, P, and Cs ions were implanted with various parameters into silicon nitride layers prepared by LPCVD. In order to get the maximum impurity concentration at the silicon nitride surface, a high temperature oxide (HTO) buffer layers was deposited prior to the implantation. Alkali ion and pH sensing properties of the layers were investigated with an electrolyte-insulator-silicon (EIS) structure using high frequency capacitance-voltage (HF-CV) measurements. The ion sensing properties of implanted silicon nitrides were compared to those of as-deposited silicon nitride. Band Cs co-implanted silicon nitrides showed a pronounced difference in pH and alkali ion sensing properties compared to those of as-deposited silicon nitride. B or P implanted silicon nitrides in contrast showed similar ion sensitivities like those of as-deposited silicon nitride.