• Annals of Clinical Microbiology
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• v.19 no.1
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• pp.20-23
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• 2016

In the RNA-based study, it is important to extract high-quality RNA. However, RNA extraction from Mycobacterium tuberculosis is problematic due to its thick, waxy cell wall rich in mycolic acid, which renders the cells resistant to lysis. Using TRIzol reagent and several powerful bead-beating steps, a high quantity of RNA was obtained.

• Journal of Microbiology and Biotechnology
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• v.34 no.3
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• pp.681-688
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• 2024

The accurate and rapid detection of methicillin-resistance of Staphylococcus aureus (SA) holds significant clinical importance. However, the methicillin-resistance detection strategies commonly require complicated cell lysis and gene extraction. Herein, we devised a novel colorimetric approach for the sensitive and accurate identification of methicillin-resistance of SA by combining allosteric probe-based target recognition with self-primer elongation-based target recycling. The PBP2a aptamer in the allosteric probe successfully identified the target MRSA, leading to the initiation of self-primer elongation based-cascade signal amplification. The peroxidase-like hemin/G-quadruplex undergo an isothermal autonomous process that effectively catalyzes the oxidation of ABTS2- and produces a distinct blue color, enabling the visual identification of MRSA at low concentrations. The method offers a shorter duration for bacteria cultivation compared to traditional susceptibility testing methods, as well as simplified manual procedures for gene analysis. The overall amplification time for this test is 60 min, and it has a detection limit of 3 CFU/ml. In addition, the approach has exceptional selectivity and reproducibility, demonstrating commendable performance when tested with real samples. Due to its advantages, this colorimetric assay exhibits considerable potential for integration into a sensor kit, thereby offering a viable and convenient alternative for the prompt and on-site detection of MRSA in patients with skin and soft tissue infections.

• Journal of Embryo Transfer
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• v.15 no.3
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• pp.247-253
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• 2000

This study was undertaken to optimize enucleation and reconstitution methods for the production of cloned mice by somatic cell nuclear transfer Outbred ICR mouse oocytes at the metapahse- II stage were retrieved from female mice superovulated by PMSG and hCG. In Experiment 1, oocytes were enucleated in medium supplemented with cytochalasin B (CCB) of 3 levels (0, 7.5 or 15 $\mu\textrm{g}$/mL), and higher rate of encleation was obtained at 7.5 and 15 $\mu\textrm{g}$/mL than at $\mu\textrm{g}$/mL. In Experiment 2, oocytes enucleated in 7.5 $\mu\textrm{g}$/mL CCB-containing medium were reconstituted with different types of somatic cell by following methods; 1) cumulus cells by direct cell injection, 2) cumulus cells by electric fusion (1.25 kV/cm, 2 pulses for each 70 $mutextrm{s}$) or 3) STO cells by the electrofusion. Electrofusion of STO cells with enucleated oocytes yielded the greatest (P<0.05) rate of reconstitution without lysis (76%) than any other combinations. Although significant decrease in the rate of somatic cell introduction was found, the electrofusion of cumulus cells yielded better rate of reconstitution than direct injection (0 vs. 18%). In Experiment 3, the duration of electric stimulation for the fusion was changed to either 50 $mutextrm{s}$ or 90 $mutextrm{s}$, but no significant improvement of reconstitution efficacy was obtained. In conclusion, this study showed that ICR mouse oocytes could be used for the production of reconstituted oocytes and a fusion method of 1.25 KV/cm with 2 pulses using 570 cell was the optimal.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1219-1225
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• 2014

Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenol molecule from green tea and is known to exhibit antioxidative as well as tumor suppressing activity. In order to examine EGCG tumor invasion and suppressing activity against adult T-cell leukemia (ATL), two HTLV-1 positive leukemia cells (HuT-102 and C91-PL) were treated with non-cytotoxic concentrations of EGCG for 2 and 4 days. Proliferation was significantly inhibited by 100 ${\mu}M$ at 4 days, with low cell lysis or cytotoxicity. HTLV-1 oncoprotein (Tax) expression in HuT-102 and C91-PL cells was inhibited by 25 ${\mu}M$ and 125 ${\mu}M$ respectively. The same concentrations of EGCG inhibited NF-kB nuclearization and stimulation of matrix metalloproteinase-9 (MMP-9) expression in both cell lines. These results indicate that EGCG can inhibit proliferation and reduce the invasive potential of HTLV-1-positive leukemia cells. It apparently exerted its effects by suppressing Tax expression, manifested by inhibiting the activation of NF-kB pathway and induction of MMP-9 transcription in HTLV-1 positive cells.

• The Korea Journal of Herbology
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• v.26 no.2
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• pp.1-10
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• 2011

Objective ： Lonicera japonica contains anti complementary polysaccharides and polyphenolic compound. Among these polyphenolic substances, chlorogenic acid is the major active component of this plant. However, the immunological mechanisms for these activities, have not been elucidated, nor the active components. To clarify immunomodulatory effects of those we examined the relationship between the activity of CD8+ T cell-mediated lysis and the frequency of cytokine profiles in spleen, thymus (especially IFN-${\gamma}$, IL-4, GM-CSF etc.) expressing CD8+ T cells activated by IL-2. Methods : To study immunomodulatory effects ethyl acetate fraction from Lonicera japonica, chlorogenic acid on cytokine gene expression from spleen, thymus cells, RT-PCR was performed after quantitative normalization for each gene by a densitometry using ${\beta}$-actin gene expression. A modified standard $^{51}Cr$-release assay was used to measure cytotoxic activities of cytotoxic T cells. Spleen, thymus cells from NOD mice were stained with CD3, CD4, CD44, CD69 in staining buffer and analyzed by two color flow cytometry. Results : We showed that ethyl acetate fraction from Lonicera japonica in combination with IL-2 resulted in a significant enhancement of PCR products for IFN-${\gamma}$, IL-4, IL-10, GM-CSF, IL-6 and cytotoxtic CD8+ T cell proportion in spleen and thymus T cells in NOD mice. This suggests that IFN-${\gamma}$, IL-6 like IL-4 may be acting as a regulatory rather than proinflammatory cytokine. Conclusions : In conclusion, based on the results of the present study which showed that ethyl acetate fraction from Lonicera japonica and chlorogenic acid upregulating cytokine gene expression in spleen and thymus, we are tempted to speculate that some of the therapeutic efficacies such as anti-diabetic activity of Lonicera japonica are due to the immunomodulatory its ethylacetate fraction and chlorogenic acid.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.398-403
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• 1999

In our previous studies, we reported that hybridoma B-lymphocytes can be used to determine the virulence of Listeria species in an in vitro cytotoxicity assay. Here, we examined the cytopathic effect, i.e., membrane damage and the nature of cell death induced by Listeria monocytogenes on murine hybridoma B-lymphocytes (Ped-2E9). Membrane damage was assessed by microscopic analyses and by measuring the release of intracellular alkaline phosphatase(AP) and lactate dehydrogenase (LDH). Cell death was determined by DNA fragmentation analyses using agarose gel electrophoresis. Infection by listeriolysin O (LLO)-producing L. monocytogenes strains induced substantial amounts of AP and LDH release from Ped-2E9 hybridoma B-cells, suggesting severe membrane damage in these cells, while an LLO-negative L. monocytogenes mutant strain had no effect. An LLO-producing recombinant L. innocua ($prifA^+hly^+$) strain also induced high AP and LDH release and cytopathic changes in Ped-2E9 cells. Light or scanning electron microscopic examination revealed L. monocytogenes mediated membrane destabilization, pore formation, intense cytoplasmic granulation, bleb formation, and lysis of Ped-2E9 cells. LLO-producing L. monocytogenes and L. innocua ($prifA^{+}hly{^}+$) also induced ladder-like DNA fragmentation in Ped-2E9 cells. Collectively, these results suggest that L. monocytogenes, specifically LLO-producing strains, can induce a severe cytopathic effect leading to apoptosis in hybridoma B-lymphocytes (Ped-2E9).

• Journal of Pharmacopuncture
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• v.10 no.3
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• pp.5-19
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• 2007

Objectives The purpose of this study was to investigate the effects of Bee Venom and Sweet Bee Venom to the primary cultured preadipocyte, adipocytes, and localized fat tissue. Methods Decreased preadipocyte proliferation and decreased lipogenesis are mechanisms to reduce obesity. So, preadipocytes and adipocytes were performed on cell cultures using Sprague-Dawley Rats and treated with 0.01-1mg/ml Bee Venom and Sweet Bee Venom. And porcine skin including fat tissue after treated Bee Venom and Sweet Bee Venom according to the dosage dependent variation are investigated the histologic changes after injection of these Pharmacopuncture. Result Following results were obtained from the preadipocyte proliferation and lipolysis of adipocyte and histologic investigation of fat tissue. 1. Bee Venom and Sweet Bee Venom showed the effect of decreased preadipocyte proliferation depend on concentration. 2. Bee Venom and Sweet Bee Venom showed the effect of decreased the activity of glycerol-3-phosphate dehydrogenase(GPDH) significantly. 3. Bee Venom was not showed the effect of lipolysis, but Sweet Bee Venom was increased in low dosage and decreased in high dosage. 4. Investigated the histologic changes in porcine fat tissue after treated Bee Venom and Sweet Bee Venom, we knew that these Pharmacopuncture was activated nonspecific lysis of cell membranes depend on concentration. Conclusion These results suggest that Bee Venom and Sweet Bee Venom efficiently induces decreased proliferation of preadipocyte and lipolysis in adipose tissue.

• Applied Biological Chemistry
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• v.24 no.4
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• pp.252-259
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• 1981

The effects of tunicamycin (TM) on the growth and ${\alpha}-amylase$ productivity of B. amyloliquefaciens K were studied. The minimal growth inhibitory concentration was $0.25{\mu}\textrm{g}/m\ell$ and its ${\alpha}-amylase$ was stable up to $50^{\circ}C$. When the saking culture with $1{\mu}\textrm{g}/m\ell$ of Tunicamycin caused the change of cell shape from form rod to irregular circular form and the mycelium lysis. the grow th of His-, $TM^{\tau}$ mutant obtained by treatment of TM and ultraviolet ray was similar to that of the parent strain, but the productivity of ${\alpha}-amylase$, protease, and RNase was lower than that of the parent.

• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.20-24
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• 2006

Plasmid DNA (pDNA) is a product of interest for many biopharmaceutical companies and research laboratories, because of increase in the number of gene therapy protocols that use nonviral vectors. This work was undertaken to study the effect of antibiotic and dissolved oxygen concentration (DOC) on the production of a ColE 1-type plasmid (pVAX1-LacZ) hosted in Escherichia coli $DH5\alpha$ and cultured in a batch fermentor with 0.751 of Terrific Broth. A decrease in the DOC from $60\%\;to\;5\%$ was shown to increase the specific pDNA concentration approximately 1.5-fold, due to the downregulation of growth. Additionally, this increase in the pDNA concentration led to a 2.2-fold increase in the purity of cell lysates obtained after cell lysis. However, the use of higher DOC led to 2.8-fold higher volumetric productivity as a consequence of a faster growth rate, reducing the fermentation time from 24 to 8 h. Interestingly, the specific pDNA concentration, and pDNA productivity and purity were always higher $(10-15\%)$ in the absence of antibiotic. Overall, the data indicate that nonselective conditions can be used without compromising yield, productivity, and purity of pDNA.

• Journal of Environmental Science International
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• v.11 no.11
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• pp.1157-1163
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• 2002

The effective removal of microcystins by chlorination was investigated on a laboratory scale. With an initial chl.a concentration of more than 1,000 $\mu\textrm{g}$/ℓ, the required chlorine dose for the effective removal of microcystins from the raw water was more than 8.0 mg/ℓ. Whereas, a chlorine dose of 3.0 mg/ℓcould effectively remove microcystins from raw water containing a chl.a concentration of less than 1,000 $\mu\textrm{g}$/ℓ. The microcystin removal was more effective below pH 8.0, plus the optimum pH range was unrelated to the concentration of toxic algal material. Although chlorination is one of the most effective methods for reducing the toxin from blue-green algae, it causes cell lysis and toxin release. However, it was demonstrated that the released cell lysates and toxins could be effectively removed by a higher dose of the oxidant. The highest removal efficiency of dissolved microcystins(initial concentration: 280 $\mu\textrm{g}$ L$\^$-1/) was with a chlorine dose of 5.0 mg/ℓ.