• Journal of Periodontal and Implant Science
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• v.43 no.6
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• pp.301-307
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• 2013

Purpose: This in vitro study was performed to assess the adherence of Porphyromonas gingivalis to a resorbable blast media (RBM) titanium surface pretreated with an ultrasonic scaler or toothbrush and to evaluate the effects of the treatment of the RBM titanium discs on the bacterial removal efficiency of brushing by crystal violet assay and scanning electron microscopy. Methods: RBM titanium discs were pretreated with one of several ultrasonic scaler tips or cleaned with a toothbrush. Then the titanium discs were incubated with P. gingivalis and the quantity of adherent bacteria was compared. The disc surfaces incubated with bacteria were brushed with a toothbrush with dentifrice. Bacteria remaining on the disc surfaces were quantified. Results: A change in morphology of the surface of the RBM titanium discs after different treatments was noted. There were no significant differences in the adherence of bacteria on the pretreated discs according to the treatment modality. Pretreatment with various instruments did not produce significant differences in the bacterial removal efficiency of brushing with dentifrice. Conclusions: Within the limits of this study, various types of mechanical instrumentation were shown to cause mechanical changes on the RBM titanium surface but did not show a significant influence on the adherence of bacteria and removal efficiency of brushing.

• Journal of Periodontal and Implant Science
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• v.24 no.3
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• pp.443-457
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• 1994

본 연구의 목적은 비외과적 치주치료시에 부가적으로 사용하기 위해 개발한 테트라싸이클린 젤의 효과를 임상지수, 치은 열구액양 및 치은열구액내 효소활성도 측정을 통해 평가함에 있다. 치주낭 깊이가 4mm 이상 6mm이하인 구치가 편악당 적어도 2개 이상 존재하는 중등도 치주염에 이환된 환자 23명을 선택하여, 한 편악에서는 치근활택술 만을 시행하였고, 다른 한 편악에는 치근활택술 후 테트라싸이클린 젤을 치은연하로 주입한 뒤 치근면 처리하였다. 사용된 임상검사 지수는 치태지수, 치은지수, 치주낭 깊이, 치은부착 상실도 및 탐침시 출혈로, 각각 치료시작 전과 치료 후 4, 12주에 검사하였으며, 치은열구액내 효소활성도 검사를 위해 치은열구액을 치료시작 전과 치료 후 1, 2, 4, 12주에 각각 채취하고 치은열구액 양을 조사한 뒤 Lactate dehydrogenase(LDH)와 Beta-glucuronidase(BG)의 활성도를 측정하였고, 효소활성도는 LDH는 340nm에서, BG는 550nm에서 각각 흡광도를 조사 분석하여 다음과 같은 결과를 얻었다. 1. 임상지수를 측정 비교한 결과 치근활택술 만으로 치료한 군과 치근활택술 후 테트라싸이클린 젤을 병용한 군 모두에서 임상적으로 치은건강의 현저한 향상을 관찰할 수 있었으나, 통계상 두 군간의 유의성있는 차이는 발견되지 않았다. 2. 치은열구액 양은 치근활택술 후 테트라싸이클린 젤을 병용한 군이 치근활택술만 시행한 군보다 치료 후 2주와 4주에 유의성 있게 감소하였다. 3. LDH와 BG 효소 활성도는 두 군 모두 현저히 감소하였고, 비록 통계학적인 유의성은 관찰할 수 없었으나 치근활택술 후 테트라싸이클린 젤을 병용한 군에서 감소량이 더 크게 나타났다.

• BMB Reports
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• v.49 no.4
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• pp.220-225
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• 2016

Cancer cells have different characteristics due to the genetic differences where these unique features may strongly influence the effectiveness of therapeutic interventions. Here, we show that the spontaneous reactivation of extracellular signalregulated kinase (ERK), distinct from conventional ERK activation, represents a potent mechanism for cancer cell survival. We studied ERK1/2 activation in vitro in SW480 colorectal cancer cells. Although ERK signaling tends to be transiently activated, we observed the delayed reactivation of ERK1/2 in epidermal growth factor (EGF)-stimulated SW480 cells. This effect was observed even after EGF withdrawal. While phosphorylated ERK1/2 translocated into the nucleus following its primary activation, it remained in the cytoplasm during late-phase activation. The inhibition of primary ERK1/2 activation or protein trafficking, blocked reactivation and concurrently increased caspase 3 activity. Our results suggest that the biphasic activation of ERK1/2 plays a role in cancer cell survival; thus, regulation of ERK1/2 activation may improve the efficacy of cancer therapies that target ERK signaling.

• Parasites, Hosts and Diseases
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• v.51 no.2
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• pp.191-196
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• 2013

The echinostome metacercariae encysted in Cipangopaludina sp. snails that were purchased from a market in Vientiane Municipality, Lao PDR, were identified as Echinostoma macrorchis (Digenea: Echinostomatidae) through recovery of adult flukes after experimental infection to rats and a cat. The metacercariae were round, $113-128(121){\times}113-125(120){\mu}m$, having a thick cyst wall, a head collar armed with collar spines, and excretory granules. The adult flukes recovered from the rats and cat at day 14 and 30 post-infection, respectively, were elongated, ventrally curved, and $3.9-6.3{\times}0.7-1.1mm$ in size. The head collar was distinct, bearing 43-45 collar spines with 5 angle spines on each side. Two testes were large (as the name implies), tandem, and slightly constricted at the middle, with irregular margins. Eggs were operculated, ovoid to elliptical, and $88-95{\times}56-60{\mu}m$. In scanning electron microscopy, the head collar was prominent, with 43-45 collar spines. Scale-like tegumental spines were densely distributed on the ventral surface between the oral and ventral suckers. Sensory papillae were distributed mainly on the tegument around the 2 suckers. It is confirmed that E. macrorchis is distributed in Lao PDR using Cipangopaludina sp. snails as the second intermediate host.

• Food Science of Animal Resources
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• v.34 no.2
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• pp.257-261
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• 2014

The objective of this study was to evaluate the effects of NaCl on the biofilm formations of the isolate from Staphylococcus aureus outbreaks linked to ham. The S. aureus ATCC13565 isolated from ham was exposed to NaCl concentrations of 0%, 2%, 4%, and 6% supplemented in tryptic soy broth (TSB) for 24 h at $35^{\circ}C$, followed by plating 0.1 mL of the culture on tryptic soy agar containing 0%, 2%, 4%, and 6% NaCl, respectively. After incubating at $35^{\circ}C$ for 24 h, the colonies on the plates were collected and diluted to $OD_{600}$ = 0.1. The diluents of S. aureus were incubated on a 96-well flat bottom plate containing TSB plus the appropriate NaCl concentrations, and the biofilm formation was quantified by crystal violet staining after being incubated at $35^{\circ}C$ for 9 h. Confocal laser scanning microscope (CLSM) was also used for visualizing the biofilm formation of S. aureus at NaCl concentrations of 0%, 2%, 4%, and 6%. The transcriptional analysis of biofilm-related genes, such as icaA, atl, clfA, fnbA, sarA, and rbf, was conducted by quantitative real-time PCR. Crystal violet staining and CLSM showed that the biofilm formations of S. aureus increased (p<0.05) along with the NaCl concentrations. Moreover, the expression of the icaA genes was higher at the NaCl concentrations of 4% and 6% as compared with 0% of NaCl by approximately 9-folds and 20-folds, respectively. These results indicated that the NaCl formulated in processed food may increase the biofilm formations of S. aureus by increasing the icaA gene expressions.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.717-721
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• 2010

The objective of this study was to evaluate the inhibition of Listeria monocytogenes growth by oleanolic acid under sublethal stresses of NaCl and pH. L. monocytogenes ATCC15313 (6 log CFU/mL) was inoculated in microplate wells containing brain heart infusion (BHI) broth supplemented with oleanolic acid in various amounts (0, 0.25, 0.5, 1.0, 1.5, 2.0, and $4.0\;{\mu}g/mL$), and different pHs (5 and 7) and NaCl concentrations (0, 3, and 6%), followed by incubation under accelerated storage condition ($37^{\circ}C$, 48 h). The optical density (OD) of the samples was measured at 0, 6, 12, 24, and 48 h at 600 nm. After the lag phase duration was observed at the early stage of incubation, the OD values of L. monocytogenes significantly increased (p<0.05) in BHI broth formulated with 0 and 3% of NaCl during accelerated storage at pH 5 and 7. However, the growth of L. monocytogenes in 6% NaCl and at less than $0.5\;{\mu}g/mL$ of oleanolic acid had no growth at pH 5 and only gradual growth at pH 7. Moreover, L. monocytogenes generally had lower OD values as the concentrations of oleanolic acid increased. As expected, the OD values of L. monocytogenes were generally higher (p<0.05) at pH 7 than at pH 5. These results indicate that oleanolic acid should be useful in inhibiting the growth of L. monocytogenes.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.618-624
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• 2002

Effect of the roasted barley tea in commercial markets on the adherence to the saliva-coated hydroxyapatite(HA) beads and the cell surface hydrophobicity of Streptococcus mutans and Streptococcus sobrinus as cariogenic microorganism was examined in vitro. Adherence activity and hydrophobicity in bacteria tested in all the barley tea samples decreased and the values were different according to the type of tea and the type of treatment. The inhibition of bacterial adsorption to HA beads suggest that barley tea active molecules as catechins and melanoidins may adsorb to a host surface, preventing the tooth receptor from interacting with any bacterial adhesions. The obtained results showed that the barley tea may inhibit bacterial adherence, the first step of the pathogenesis of dental caries in which these microorganism are involved.

• Proceedings of the Microbiological Society of Korea Conference
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• 2002.10a
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• pp.121-124
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• 2002

This work was initiated to develope a recombinant oral poliovaccine (OPV), which is highly advanced in safety (minimizing VAPP) by introducing Type 2,3 poliovirus epitopes into our RPS-Vax system. We have introduced several potential vaccine epitopes of poliovirus Type 2, and 3 into RPS-Vax system, resulting in production of recombinant polioviruses. Any of these chimeric viruses, however, were not detected for their foreign gene expression by serotype-specific mouse antiserum. We have designed several folding units to stabilize the introduced vaccine protein and attached short epitope-concatamer or epitope-multimer to them, followed by production of chimeric viruses. Only those who have an HIV-1 Tat-mediated folding unit were nicely detected for the introduced foreign proteins by anti-Tat antiserum and type-specific peptide-induced antisera. Nevertheless, introduced epitopes were not detected in Western blot experiment with each serotype-specific antiserum. None of the mice inoculated with these chimeric viruses showed preventative immunity when challenged with Lansing and Leon wildtype 2 and 3 poliovirus, and the antiserum did not show neutralizing capacity in vitro. Conformational epitope covering B/C loop region of type 2 and 3 were newly designed by computer modeling, and introduced into the RPS-Vax vector system, followed by production of chimeric viruses. Introduced epitope regions were nicely detected by anti-Tag23 mAb or peptide antibody, but still not detected by poliovirus antiserum. Nevertheless, neutralizing antibody was detected in the Tg-PVR mice even when inoculated once with these chimeric viruses. Also, the immunized mice showed perfect preventative immunity against the wild Type poliovirus Lancing or Leon. When boosted appropriately, those chimeric virus-inoculated Tg-PVR mice produced equivalent amounts of neutralizing antibody to those in Sabin 2/3-immunized mice. These data strongly suggest that our recombinant poliovirus (RPS-PV2 and RPS-PV3) can be used as a safe and effective rec-OPV instead of any preexisting poliovaccine.

• Food Science of Animal Resources
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• v.37 no.4
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• pp.502-510
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• 2017

This study investigated bacterial growth-inhibitory effect of 69 therapeutic herbal plants extracts on 9 bacterial strains using a disc diffusion assay. Especially, the antimicrobial activity of Psoraleae semen, which showed different activity on pathogenic Gram-positive and Gram-negative bacteria, was evaluated by MIC (minimal inhibition concentration) and biofilm formation assay. The effect of Psoraleae semen extract on bacterial cell membranes was examined by measurement of protein leakage (optical density at 280 nm) and scanning electron microscope (SEM). No clear zone was formed on discs containing Gram-negative bacteria, but Gram-positive bacteria exhibited clear zones. The MICs of Psoraleae semen extract were $8{\mu}g/mL$ for Streptococcus mutans, and $16{\mu}g/mL$ for Enterococci and Staphylococcus aureus. In addition, biofilm formation was inhibited at concentration $8-16{\mu}g/mL$. Protein leakage values and SEM images revealed that cell membranes of Gram-positive bacteria were impaired following exposure to the extract. Further, the extract inhibited the growth of Listeria monocytogenes in sausages. These results indicate that Psoraleae semen extract could be utilized as a natural antimicrobial agent against Gram-positive bacteria.

• Korean Journal of Microbiology
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• v.36 no.1
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• pp.64-68
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• 2000

The immunopotentiating effects of the polysaccharides, both intracellular and extracellular, was examined by an animal feeding test. The results are summarized as follows. The oral administration of intracellular and extracellular polysaccharides of Agrocybe cylindracea for 10 days resulted in the enhanced phagocytic activity of peritoneal exudate cells(PEC), spleen cells(SC), and monolymphocytes(ML). In the experiment of PFC(plaque forming cell) and RFC(rosette forming cell), the results showed that all the polysaccharide fractions enhanced the immune related cells. The EAC II group(the extracellular polysaccharide of Agrocybe cylindracea 10 mg/0.2 ml distilled water/day/ mouse) increased the PFC and RFC by 46~50% and 43%, respectively, compared to the control group. On the other hand, the IAC I group(the intracellular polysaccharide of Agrocybe cylindracea 1 mg/0.2 ml distilled water/day/mouse) increased the PFC and RFC by 49~70% and 91%, respectively. In terms of the mitogenic activity, the extracellular polysaccharides of A. cylindracea showed a higher activity than the intracellular polysaccharides.