• Korean Journal of Animal Reproduction
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• v.22 no.1
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• pp.89-94
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• 1998

A study was made to investigate the effects of concerning factors with IGF-I recovery on the final IGF-I concentration in the effluent and to establish recovery conditions of IGF-I using liquid emulsion membranes(LEM). D2EHPA was best carrier among Amberlite LA2, Aliquit 336 and D2EHPA for recovery rate of IGF-I. Recovery rate of IGF-I by D2EHPA volume in the oil phase was increased as increasing D2EHPA volume, and optimal volume of D2EHPA was 5% in this experiment. The recovery rate of IGF-I by D2EHPA was increased by the decreasing from pH 7 to pH 4 of external phase. Therefore, optimal pH value was 4.0. Optimal concentrations of sulfuric acid in internal phase, paraffin oil in oil phase and Span 80 for recovery rate of IGF-I were 0.1M, 2.0% and 5%, respectively, and optimal W/O rate was 2. These results suggested that optimal conditions for recovery of IGF-I were D2EHPA(5%) as carrier, pH 4.0, 0.1M sulfuric acid, 2% paraffin oil, 2.0 W/O rate and 5.0% Span 80.

• Journal of Life Science
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• v.10 no.6
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• pp.621-629
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• 2000

Camptothecin (CPT) is an antitumor alkaloid that has been isolated from the Chinese tree, Camptotheca acuminata. The cytotoxicity of CPT has been correlated to its inhibition of DNA topoisomerase (Topo) I by stabilizing drug-enzyme-DNA “cleavable complex" resulting in DNA single-strand breaks and DNA-protein crosslinks. This studies were designed to elucidate whether CPT regulates Topo I mediated by CPT in DNAs containing c-myc protooncogene. We have conducted experiments on Topo I purification, pUC-MYC I cloning and Topo I assay using electrophoresis, quantitative RT-PCR and Northern blotting techniques. CPT ingibited the relaxation activity of Topo I in pUC19 DNA at various concentrations (1-1000 $\mu$M), while it enhanced the cleavage of Topo I in the pUC-MYC I by forming a cleavable complex at relatively high concentrations (100-1000 $\mu$M). In HL-60 cells treated with CPT, the expression of c-myc gene was decreased over that in the control group with no changes in the expression of Topo I mRNA. Our results suggest that Topo I is the target of CPT cytotoxicity but it does not affect Topo I extression, and the suppression of c-myc mRNA expression by CPT is due to c-myc damage resulted from formation of a cleavable complex with CPT. CPT.

• Honam Mathematical Journal
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• v.27 no.3
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• pp.399-404
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• 2005

Let M be a finite commutative nilpotent algebra over a perfect field k of prime characteristic p and let $M^p$ be the sub-algebra of M generated by $x^p$, $x{\in}M$. Eggert[3] conjectures that $dim_kM{\geq}pdim_kM^p$. In this paper, we show that the conjecture holds for $M=R^+/I$, where $R=k[X_1,\;X_2,\;{\cdots},\;X_t]$ is a polynomial ring with indeterminates $X_1,\;X_2,\;{\cdots},\;X_t$ over k and $R^+$ is the maximal ideal of R generated by $X_1,\;X_2,{\cdots},\;X_t$ and I is a monomial ideal of R containing $X_1^{n_1+1},\;X_2^{n_2+1},\;{\cdots},\;X_t^{n_t+1}$ ($n_i{\geq}0$ for all i).

• Structural Engineering and Mechanics
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• v.39 no.2
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• pp.287-301
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• 2011

This paper is focused on the residual capacity of steel columns, as a damage criterion. Load-Impulse (P-I) diagrams are frequently used for analysis, design, or assessment of blast resistant structures. The residual load carrying capacity of a simply supported steel column was derived as a damage criterion based on a SDOF computational approach. Dimensionless P-I diagrams were generated numerically with this quantitative damage criterion. These numerical P-I diagrams were used to show that traditional constant ductility ratios adopted as damage criteria are not appropriate for either the design or damage assessment of blast resistant steel columns, and that the current approach could be a much more appropriate alternative.

• Development and Reproduction
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• v.10 no.2
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• pp.85-92
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• 2006

Progesterone(P4) is an important intermediate in the synthesis of androgens and estrogens. Furthermore, P4 itself plays a crucial role in ovulation, atresia and luteinization, and is essential for the continuation of early pregnancy in all mammalian species. In spite of the hormone's physiological importance, the exact action mechanism(s) of P4 in mammalian ovary has not been fully understood yet. In this context, a decades-long controversy regarding the identity of receptors that mediate non-genomic, transcription-independent cellular responses to P4 is presently attracting huge scientific interests. P4 may exert its action in mammalian ovary by several ways: 1) the well-documented genomic pathway, involving hormone binding to so-called classic cytosolic receptor(PGR) and subsequent modulation of gene expression by the ligand-receptor complex as transcription factor. 2) pathways are operating that do not act on the genome, therefore refered to as non-genomic actions. The prominent characteristics of the non-genomic P4 actions are: (i) rapid, (ii) insensitive to transcription inhibitors, (iii) transduced by membrane associated molecules. In particular, the non-genomic P4 actions could be mediated by: (a) classic genomic P4 receptor(PGR) that localizes at or near the plasma membrane, (b) a family of membrane progestin receptors(MPR $\alpha$, MPR $\beta$ and MPR $\gamma$), (c) progesterone receptor membrane component I(PGRMC1), and (d) a membrane complex composed of serpine I mRNA binding protein(SERBP1). The present review summarized these rapid signaling pathways of P4 in the mammalian ovary.

• Journal of Sensor Science and Technology
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• v.1 no.1
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• pp.5-12
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• 1992

We have fabricated a-Si:H multilayer for contact-type linear image sensor by means of RF glow discharge decomposition method. The ITO/i-a-Si:H/Al structure has relatively high dark current due to indium diffusion and carrier injection from both electrodes, resulting in low photocurrent to dark current. To suppress the dark current and to enhance interface electric field between ITO and i-a-Si:H film we have fabricated ITO/insulator/i-a-S:H/p-a-S:H/Al multilayer film with blocking structure. The photocurrent of ITO/$SiO_{2}(300{\AA})$/i-a-Si:H/p-a-Si:H($1500{\AA}$)/Al multilayer sensor with 5V bias voltage became saturated at about 20nA under $20{\mu}W/cm^{2}$ light intensity, while the dark current was less than 0.1nA. To increase the light generation efficiency we have adopted ITO/$SiO_{x}N_{y}(300{\AA})$/i-a-Si:H/p-a-Si:H($1500{\AA}$)/Al structure, showing photocurrent of 30nA and dark current of 0.08nA with 5V bias voltage. Also the spectral photosensitivity of the multilayer was enhanced for short wavelength visible region of 560nm, compared with that of the a-Si:H monolayer of 630nm. And its photoresponse time was about 0.3msec with the film homogeneity of 5% deviation.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.6
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• pp.479-485
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• 2001

The existence of opioid receptors in mammalian cerebellum except human, has not been clearly understood. In the present study, we found that NPY was inducible by morphine in the mouse cerebellar granular and Purkinje cell layers. We performed in situ RT-PCR and immunohistochemistry to characterize the NPY expression. The increase of NPY gene expression by morphine (30 mg/kg, i.p.) was inhibited by pretreatment with not only naloxone (100 mg/kg, i.p.) but also a noncompetitive NMDA antagonist, MK-801 (0.3 mg/kg, i.p.). The competitive NMDA antagonist, AP-5 (0.9 mg/kg, i.p.) slightly attenuated the increased NPY expression by morphine. Also, the finding similar to morphine was shown by NMDA (70 mg/kg, i.p.) treatment. Our results indicate that NPY was inducible by morphine and this might reflect activation of NMDA receptors in granule cells that relay mossy fiber inputs to Purkinje cells via parallel fibers.

• Journal of Trauma and Injury
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• v.34 no.1
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• pp.31-38
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• 2021

Purpose: Traumatic vertebral injuries have a prevalence of 4-5% at level I centers. Studies have demonstrated that isolated thoracolumbar transverse process fractures (iTPF) rarely require brace or surgical interventions. We hypothesized that similarly isolated thoracolumbar spinous process fractures (iSPF) would have less need for bracing and operative interventions than SPFs with associated vertebral body (VB) fractures (SPF+VB). We performed a similar analysis for iTPF compared to transverse process fractures associated with VB injury (TPF+VB). Methods: In this single-center, retrospective study from 2012 to 2016, patients were classified into iSPF, SPF+VB, iTPF, and TPF+VB groups. Data including the fracture pattern, neurologic deficits, and operative intervention were obtained. The primary outcome studied was the need for bracing and/or surgery. A statistical analysis was conducted. Results: Of 98 patients with spinous process fractures, 21 had iSPF and 77 had SPF+VB. No iSPF patients underwent surgery, whereas 24 (31.17%) SPF+VB patients did undergo surgery (p=0.012). In the iSPF group, three patients (15%) received braces only for comfort, whereas 37 (48.68%) of the SPF+VB group required bracing (p=0.058). Of 474 patients with transverse process fractures, 335 had iTPF and 139 had TPF+VB. No iTPF patients underwent surgery, whereas 28 (20.14%) TPF+VB patients did (p≤0.001). Of the iTPF patients, six (1.86%) were recommended to receive braces only for comfort, while 68 (50.75%) of the TPF+VB patients required bracing (p<0.001). Conclusions: No patients with iSPF or iTPF required surgical intervention, and bracing was recommended to patients in these groups for comfort only. It appears that these injures may be safely managed without interventions, calling into question the need for spine consultation.

• Korean Journal of Microbiology
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• v.23 no.1
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• pp.13-19
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• 1985

Acc I endonuclease has been isolated from 300g (wet weight) cells of Acinetobacter calcoaceticus. The cells were broken by using French press at 20, 000p.s.i. After ammonium sulfate fractionation, the enzyme was further purified by heparin agarose, DEAE-sephades, Affi.-gel Blue, phosphocellulose, and hydroxylapatite column chromatography. The purified Acc I endonudlease has a single polypeptide species and its subunit molecular weight was 45,000 ${\pm}$ 1,000 daltons as judged by 10% SDS-polyacrylamide gel electrophoresis. The isolated enzyme was essentially free of contaminating nucleases as judged by homochromatography by using a $^{32}P-labeled$ oligonucleotide. The enzyme showed maximum activity at pH values between 8.0 and 11.0 and in the presence of $MgCl_2$. Acc I endonuclease was maximally active in the absence of NaCl and was completely inhibited at 200 mM NaCl.

• Journal of the Korean Mathematical Society
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• v.32 no.3
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• pp.427-446
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• 1995

Let S be a set and B be a $\sigma$-field on S. We consider $(\Omega = S^Z, T = B^z, P)$ as the basic probability space. We denote by T the left shift on $\Omega$. We assume that P is invariant under T, i.e., $PT^{-1} = P$, and that T is ergodic. We denote by $X = \cdots, X_-1, X_0, X_1, \cdots$ the coordinate maps on $\Omega$. From our assumptions it follows that ${X_i}_{i \in Z}$ is a stationary and ergodic process.