• Parasites, Hosts and Diseases
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• v.30 no.1
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• pp.33-42
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• 1992

Naegleria fowleri, a free-living amoeba commonly found in moist soil and fresh water, enters the body via the nasal mucosa and migrates along the olfactory nerve to t he brain, where it causes acute amoebic meningoencephalitis. In the present study 7 clones secreting monoclonal antibodies (McAbs) against N. fowleri were produced and the effector function of them was investigated. Their isotopes were IgGl (Nf 1, Nf 154), 19G3 (Nf 137) and 19A (Nf 1, Nf 2, Nf 256, Nf 279). Five McAbs (McAb Nf 2, Nf 279, Nf 27, Nf 154, Nf 137) were specific for N. fowleri by ELISA and recognized the antigenic determinants located on the trophoBoite surface by IFAT and immunoperoxidase stain. These aye McAbs had capacity to agglutinate N. fowleri trophozoites and inhibited the growth of the amoeba in culture medium. McAb Nf 2 inhibited proliferation of trophozoites in vitro significantly. Also the cytotoxicity of JV. fowleri against CHO cell was reduced in the presence of McAb Nf 2 and McAb Nf 154. From these results McAb Nf 2 was confirmed to weaken the virulence of the amoeba among 7 screened McAbs.

• BMB Reports
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• v.33 no.6
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• pp.519-524
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• 2000

NF1 proteins are a family of DNA binding proteins which consist of two separate domains, N-terminal DNA binding domain and C-terminal transcription activation domain. The N-terminal 220 amino acids are highly conserved and are also known to mediate dimerization of NF1 proteins. The C-terminal regions of different type of NF1 proteins are heterogeneous and responsible for transcriptional activation. In this study, we tested the interaction between different domains of rat NF1-A protein by yeast two hybrid analysis and observed the interaction between C-terminal regions of NF1-A which do not contain the N-terminal dimerization domain. Our results showed that the C-terminal region of rat NF1-A between residues 231 and 509 strongly interacted not only with itself, but also with human NF1/CTF1 which is a different type of NF1. When the C-terminal region was divided into two fragments, one from residue 231 to 447 and the other from 448 to 509, the two fragments were able to interact with the C-terminal region of NF1-A significantly. This indicates that both fragments contain independent interaction domains. Analysis of the interactions with alanine substituted fragments showed that substitutions of the heptasequence, SPTSPTY of NF1-A, affected interaction between NF1 proteins. Our results strongly suggest that C-terminal regions may also be important for the formation of homo- and heterodimers in addition to the N-terminal dimerization domain. Also, the heptasequence motif may play some roles in dimer formation.

• BMB Reports
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• v.44 no.8
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• pp.553-557
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• 2011

We previously reported that CDK2/Cyclin A can phosphorylate and activate the transcription factor NF-Y. In this study, we investigated a potential regulatory role for NF-Y in the transcription of Cyclin A and other cell cycle regulatory genes. Gel-shift assays demonstrate that NF-Y binds to CCAAT sequences in the Cyclin A promoter, as well as to those in the promoters of cell cycle G2 regulators such as CDC2, Cyclin B and CDC25C. Furthermore, expression of Cyclin A increases NF-Y's affinity for CCAAT sequences in the CDC2 promoter; however, Cyclin A's induction of CDC2 transcription is antagonized by p21, an inhibitor of CDK2/Cyclin A. These results suggest a model wherein NF-Y binds to and activates transcription from the Cyclin A promoter, increasing cellular levels of Cyclin A/CDK2 and potentiating NF-Y's capacity for transcriptional transactivation, and imply a positive feedback loop between NF-Y and Cyclin A/CDK2. Our findings are additionally indicative of a role for Cyclin A in activating Cyclin B/CDK1 through promoting NF-Y dependent transcription of Cyclin B and CDC2; NF-Y mediated crosstalk may therefore help to orchestrate cell-cycle progression.

• Journal of Genetic Medicine
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• v.21 no.1
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• pp.22-30
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• 2024

Purpose: Neurofibromatosis 1 (NF1) is one of the most common autosomal dominant diseases caused by heterozygous mutation in the NF1 gene. Mutation detection is complex owing to the large size of the NF1 gene, the presence of a high number of partial pseudogenes, and the great variety of mutations. We aimed to study the mutation spectrum of NF1 gene in Korean patients with NF1. Materials and Methods: We have analyzed total 69 unrelated patients who were clinically diagnosed with NF1. PCR and sequencing of the NF1 gene was performed in all unrelated index patients. Additionally, multiplex ligation-dependent probe amplification (MLPA) test of the NF1 and SPRED1 gene analysis (sequencing and MLPA test) were performed in patients with negative results from NF1 gene sequencing analysis. Results: Fifty-five different variants were identified in 60 individuals, including six novel variants. The mutations included 36 single base substitutions (15 missense and 21 nonsense), eight splicing mutations, 13 small insertion or deletions, and three gross deletions. Most pathogenic variants were unique. The mutations were evenly distributed across exon one through 58 of NF1, and no mutational hot spots were found. When fulfilling the National Institutes of Health criterion for the clinical diagnosis of NF1, the detection rate was 84.1%. Cafe-au-lait macules were observed in all patients with NF1 mutations. There is no clear relationship between specific mutations and clinical features. Conclusion: This study revealed a wide spectrum and genetic basis of patients with NF1 in Korea. Our results aim to contribute genetic management and counseling.

• The Journal of Pediatrics of Korean Medicine
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• v.15 no.2
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• pp.69-73
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• 2001

The neurofibromatosis (NF) are a set of genetic disorders which cause tumors to grow along various types of nerves and, in addition, can affect the development of non-nervous tissues such as bones and skin. NF causes tumors to grow anywhere on or in the body. It also leads to developmental abnormalities. For example, individuals with NF have a higher incidence of learning disabilities. Neurofibromatosis(NF) has been classified into two distinct types: NF-I and NF-II. neurofibromatosis 1(NF-I), also known as von Recklinghausen NF or Peripheral NF, occurring in 1:4,000 births, is characterized by multiple cafe-au-lait spots and neurofibromas on or under the skin. Enlargement and deformation of bones and curvature of the spine (scoliosis) may also occur. Occasionally, tumors may develop in the brain, on cranial nerves, or on the spinal cord. About 50% of people with NF also have learning disabilities. Neurofibromatosis 2(NF-II), also known as Bilateral Acoustic NF(BAN), is much rarer occurring in 1:50,000 births. NF-II is characterized by multiple tumors on the cranial and spinal nerves, and by other lesions of the brain and spinal cord. Tumors affecting both of the auditory nerves are the hallmark. Hearing loss beginning in the teens or early twenties is generally the first symptom. We reported a 10-year-old female patient with NF-I, she has pain and edema in left leg, no symptoms of NF.

• Molecules and Cells
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• v.20 no.2
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• pp.241-246
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• 2005

PDK-1 activates PI3-kinase/Akt signaling and regulates fundamental cellular functions, such as growth and survival. NF-${\kappa}B$ is involved in the induction of a variety of cellular genes affecting immunity, inflammation and the resistance to apoptosis induced by some anti-cancer drugs. Even though the crucial involvement of the PI3-kinase/Akt pathway in the anti-apoptotic activation of NF-${\kappa}B$ is well known, the exact role of PDK-1 as well as PI3-kinase/Akt in NF-vactivation is not understood. Here we demonstrate that PDK-1 plays a pivotal role in transcriptional activation of NF-${\kappa}B$ by dissociating the transcriptional co-repressor HDAC1 from the p65 subunit of NF-${\kappa}B$. The association of CBP with p65 was not directly modulated by PDK-1 or by PI3-kinase. Etoposide activated NF-${\kappa}B$ through PI3-kinase/Akt, and the transcription activation domain (TAD) of p65 was further activated by wild-type PDK-1. Overexpression of a dominant negative PDK-1 mutant decreased etoposide-induced NF-${\kappa}B$ transcription and further down-regulated the ectopic HDAC1-mediated decrease in NF-${\kappa}B$ transcriptional activity. Thus activation of PDK-1 relieves the HDAC1-mediated repression of NF-${\kappa}B$ that may be related to basal as well as activated transcription by NF-${\kappa}B$. This effect may also explain the role of the PI3-kinase/PDK-1 pathway in the anti-apoptotic function of NF-${\kappa}B$ associated with the chemoresistance of cancer cells.

• Molecules and Cells
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• v.20 no.1
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• pp.105-111
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• 2005

Mannasantin B, a dilignan structurally related to manssantin A, is an inhibitor of NF-${\kappa}B$ transactivation. In the present study, we found that it inhibited PMA-induced expression of IL-$1{\beta}$, IL-$1{\beta}$ mRNA, and IL-$1{\beta}$ promoter activity in U937 cells with $IC_{50}$ values of about 50 nM. It also inhibited NF-IL6- and NF-${\kappa}B$-induced activation of IL-$1{\beta}$, with $IC_{50}$ values of 78 nM and $1.6{\mu}M$, respectively, revealing a potent inhibitory effect on NF-IL6. Electrophoretic mobility shift assays showed that manassantin B had an inhibitory effect on DNA binding by NF-IL6, but not by NF-${\kappa}B$. Further analysis revealed that transactivation by NF-IL6 was also inhibited. Our results indicate that manassantin B suppresses expression of IL-$1{\beta}$ in promonocytic cells by inhibiting not only NF-${\kappa}B$ but also NF-IL6 activity. Furthermore, our observations suggest that manassantin B may be clinically useful as a potent inhibitor of NF-IL6 activity.

• Journal of the Korean earth science society
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• v.39 no.6
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• pp.519-532
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• 2018

We investigated the effect of galactic plane toward molecular motion and kinematics in the northern filament (NF) of Orion Molecular Clouds Complex (OMC) using $^{12}CO$ (J=1-0) line. Observed data were from three areas including NF1, NF2, and NF3 in far-out order from galactic plane, for a total 270 hours by Seoul National University Radio Astronomy Observatory (SRAO) 6m telescope, with 2arcmin spatial resolution. galactic plane and OMC NF were connected to each other along the magnetic field at a density of 3% for $^{12}CO$ (J=2-1) and 9% for the case of dust. $^{12}CO$ (J=1-0), $^{12}CO$ (J=2-1), and interstellar dusts were distributed uniformly in NF3, but only in certain regions with relatively high density in NF1 and NF2. NF showed a single structure, partial shrinking motion in NF1, and rotational motion at the bottom of NF2, and spiral rotation associated with magnetic field only in NF3. The position-velocity analysis showed that the materials including $^{12}CO$ (J=1-0) could flow toward galactic plane along NF2 and NF3. However, there was no clear cause for the material to flow toward galactic plane in this result. Further detailed observation for rotational motion at the top of NF1 and NF2 might help to confirm it.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.128-128
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• 2018

Nypa fruticans wurmb (NF) has been used as traditional medicinal food in Asian countries. Especially, NF has been used for conventional medicine to treat inflammatory periodontal diseases. Previous studies have been shown that NF has large amount of useful constituents such as phenolic acids, polyphenols and flavonoids. Also, NF is known as having medicinal effects such as anti-oxidant, anti-inflammatory and cholesterol-lowering effects. NF has recently been attracted to use complementary medicinal food on inflammatory diseases in Korea. However, there are no obvious effects in inflammatory and metabolic diseases also mechanisms has been studied yet. The purpose of this study was to investigate the anti-inflammatory effects of NF and steamed-NF (SNF), which recently has been used as health food, using Human keratinocyte cell line (HaCaT) and Human mast cell line (HMC-1). The cytotoxicities of NF and SNF were measured by using MTT assays in HaCaT cells and HMC-1 cell. To evaluate anti-inflammatory effects of NF and SNF, HaCaT cells were stimulated with tumor necrosis factor $(TNF)-{\alpha}$ and Interferon $(IFN)-{\gamma}$. Also, HMC-1 cells were stimulated with phorbol-12-myristate-13-acetate (PMA) and A23187 calcium ionophore (A23187) to induce allergic inflammation. Inflammatory cytokine were measured by enzyme-linked immunosorbent assay (ELISA). In this result, the extract of NF and SNF (0.01 - 1mg/ml) did not show cytotoxicity in HaCaT cells and HMC-1 cells. In addition, the NF and SNF suppressed the production of interleukin (IL)-6 and IL-8 in HaCaT cells at highest concentration. Furthermore, the treatment of SNF significantly inhibited the secretion level of IL-8 in PMA plus A23187-stimulated HMC-1 cells compared with NF treatment group. These results suggest that the extract of NF and SNF may serve as a potential therapy for skin inflammatory diseases.

• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.488-498
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• 2003

Background : Activation of the transcription factor NF-${\kappa}B$ has been shown to protect cells from tumor necrosis factor-alpha, chemotherapy, and radiation-induced apoptosis. NF-${\kappa}B$-dependent cIAP expression is a major antiapoptotic mechanism for that. NF-${\kappa}B$ activation and cIAP expression in A549 lung cancer cells which is relatively resistant to radiation-induced cell death were investigated for the mechanism of radioresistance. Materials and methods : We used A549 lung cancer cells and Clinac 1800C linear accelerator for radiation. Cell viability test was done by MTT assay. NF-${\kappa}B$ activation was tested by luciferase reporter gene assay, Western blot for $I{\kappa}B{\alpha}$ degradation, and electromobility shift assay. For blocking ${\kappa}B$, MG132 and transfection of $I{\kappa}B{\alpha}$-superrepressor plasmid construct were used. cIAP expression was analyzed by RT-PCR and cIAP2 promoter activity was performed using luciferase assay system. Results : MTT assay showed that cytotoxicity even 48 hr after radiation in A549 cells were less than 20%. Luciferas assay demonstrated weak NF-${\kappa}B$ activation of $1.6{\pm}0.2$ fold compared to PMA-induced $3.4{\pm}0.9$ fold. Radiation-induced $I{\kappa}B{\alpha}$ degradation was observed in Western blot and NF-${\kappa}B$ DNA binding was confirmed by EMSA. However, blocking NF-${\kappa}B$ using MG132 and $I{\kappa}B{\alpha}$-superrepressor transfection did not show any sensitizing effect for radiation-induced cell death. The result of RT-PCR for cIAP1 & 2 expression was negative induction while TNF-${\alpha}$ showed strong expression for cIAP1 & 2. The cIAP2 promoter activity also did not show any change compared to positive control with TNF-${\alpha}$. Conclusion : We conclude that activation of NF-${\kappa}B$ does not determine the intrinsic radiosensitivity of cancer cells, at least for the cell lines tested in this study.