• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.31.1-31.20
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• 2020

Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were "matrix metalloproteinases", "collagen", and "dentin" and "hybrid layer". MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (synthetic-peptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.

• Journal of Radiation Industry
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• v.9 no.4
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• pp.193-198
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• 2015

Most of targeted therapies block the action of certain enzymes, proteins, or other molecules involved in the growth and spread of cancer cells to produce its cytotoxic effect. Either small molecule drugs or monoclonal antibodies are mostly used in targeted therapies. Unfortunately, targeted therapy has a certain degree of unwanted side effect like other cytotoxicity inducing chemotherapies. To overcome and to reduce unwanted side effects during a cancer therapy, recently radiopeptide therapies has got the worlds' attraction for the tumor targeting modalities due to its beneficial effect on less side effect compared to cytotoxic chemotherapies. Among radiopeptide therapies, $^{177}Lu$-DOTATATE is a major modality as an effective one invented so far in treating neuroendocrine tumor (NET) and it has been in clinical trials at least one decade. Although it does have rather effective therapeutic effect on NET, it has less effective in rather large solid tumor. There are many ways to improve or increase therapeutic effect of radiopeptide are a finding the potent small molecules to target the tumor site selectively, or a labeling with radioisotope of emitting high energy, or an improving its biological half-life by introducing different moieties to increase lipophilicity. Present study was focus to increase a biological half-life of radio somatostatin which will target the somatostatin receptor by altering the bifunctional chelator (BFCA) by introducing lipophilic moiety to the somatostatin, which would make the labeled peptide stay longer in the tumor site and thus it can intensify the therapeutic effect on tumor cell itself and around tissues.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2342-2348
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• 2014

Poly(lactic-co-glycolic acid) (PLGA) were grafted to both ends of Pluronic$^{(R)}$ F68 ($(EO)_{75}(PO)_{30}(EO)_{75}$) triblock copolymer to produce poly{(lactic acid)$_m$-co-(glycolic acid)$_n$}-b-poly(ethylene oxide)$_{75}$-b-poly(propylene oxide)$_{30}$-b-poly(ethylene oxide)$_{75}$-b-poly{(lactic acid)$_m$-co-(glycolic acid)$_n$} (PLGA-F68-PLGA) pentablock copolymers. Molecular weights of PLGA blocks were controlled and five kinds of pentablock copolymers with different PLGA block lengths were synthesized using in-situ ring-opening polymerization of D,L-lactide and glycolide with tin(II) 2-ethylhexanoate ($Sn(Oct)_2$) catalyst. PLGA-F68-PLGA pentablock copolymers were characterized by $^1H$- and $^{13}C$-NMR, GPC, and TGA. The numbers (2m, 2n) of repeating units for lactic acid and glycolic acid inside PLGA segments were obtained as (48, 17), (90, 23), (125, 40), (180, 59), and (246, 64), with $^1H$-NMR measurement. From NMR data, the resultant molecular weights were determined in the range of 12,700-29,700, which were similar to those obtained from GPC. Polydispersity index was increased in the range of 1.32-1.91 as the content of PLGA blocks increased. TG and DTG thermograms showed discrete degradation traces for PLGA and F68 blocks, which indicate the weight fractions of PLGA blocks in pentablock copolymers can be calculated by TG profile and it is possible to remove PLGA block selectively. Hydrodynamic radius and radius of gyration of pentablock copolymer micelle were obtained in the range of 46-68 nm and 31-49 nm, respectively, in very dilute (i.e. 0.005 wt %) aqueous solution of THF:$H_2O$ = 10:90 by volume at $25^{\circ}C$.

• The KIPS Transactions:PartC
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• v.13C no.1 s.104
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• pp.83-94
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• 2006

This paper describes ATM cell encipherment method using Rijndael Algorithm adopted as an AES(Advanced Encryption Standard) by NIST in 2001. ISO 9160 describes the requirement of physical layer data processing in encryption/decryption. For the description of ATM cell encipherment method, we implemented ATM data encipherment equipment which satisfies the requirements of ISO 9160, and verified the encipherment/decipherment processing at ATM STM-1 rate(155.52Mbps). The DES algorithm can process data in the block size of 64 bits and its key length is 64 bits, but the Rijndael algorithm can process data in the block size of 128 bits and the key length of 128, 192, or 256 bits selectively. So it is more flexible in high bit rate data processing and stronger in encription strength than DES. For tile real time encryption of high bit rate data stream. Rijndael algorithm was implemented in FPGA in this experiment. The boundary of serial UNI cell was detected by the CRC method, and in the case of user data cell the payload of 48 octets (384 bits) is converted in parallel and transferred to 3 Rijndael encipherment module in the block size of 128 bits individually. After completion of encryption, the header stored in buffer is attached to the enciphered payload and retransmitted in the format of cell. At the receiving end, the boundary of ceil is detected by the CRC method and the payload type is decided. n the payload type is the user data cell, the payload of the cell is transferred to the 3-Rijndael decryption module in the block sire of 128 bits for decryption of data. And in the case of maintenance cell, the payload is extracted without decryption processing.

• Journal of Chest Surgery
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• v.52 no.6
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• pp.392-399
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• 2019

Background: The surgical strategies for carotid endarterectomy (CEA) vary in terms of the anesthesia method, neurological monitoring, shunt usage, and closure technique, and no gold-standard procedure has been established yet. We aimed to analyze the feasibility and benefits of CEA under regional anesthesia (RA) and CEA under general anesthesia (GA). Methods: Between June 2012 and December 2017, 65 patients who had undergone CEA were enrolled, and their medical records were prospectively collected and retrospectively reviewed. A total of 35 patients underwent CEA under RA with cervical plexus block, whereas 30 patients underwent CEA under GA. In the RA group, a carotid shunt was selectively used for patients who exhibited negative results on the awake test. In contrast, such a shunt was used for all patients in the GA group. Results: There were no cases of postoperative stroke, cardiovascular events, or mortality. Nerve injuries were noted in 4 patients (3 in the RA group and 1 in the GA group), but they fully recovered prior to discharge. Operative time and clamp time were shorter in the RA group than in the GA group (119.29±27.71 min vs. 161.43±20.79 min, p<0.001; 30.57±6.80 min vs. 51.77±13.38 min, p<0.001, respectively). The hospital stay was shorter in the RA group than in the GA group (14.6±5.05 days vs. 18.97±8.92 days, p=0.022). None of the patients experienced a stroke or restenosis during the 27.23±20.3-month follow-up period. Conclusion: RA with a reliable awake test reduces shunt use and decreases the clamp and operative times of CEA, eventually resulting in a reduced length of hospital stay.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.535-543
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• 1998

In the present study, we designed and constructed new microdialysis probe in order to improve the efficacy and accuracy of microdialysis method. In addition, extracellular concentrations of GABA, glutamate, aspartate and glycine were monitored with new designed probe in the lateral portion of the ventrocaudal periaqueductal gray using unanesthetized and unrestrained rats. Furthermore, the effect of opiates on release of these amino acids, especially GABA, was analyzed by measuring their concentration in PAG dialysates following veratridine administration in the presence of systemic morphine. The results were summerized as follow : 1. The damaging rates of 1.0mm or 1.5mm window probe were 12.5% or 42.8%, respectively. In the group using 1.5mm window probe, the damaging area was extended into mesencephalic aqueduct because of microdialyzing pressure. 2. Because of the unique design of our probes with an opening facing one side, dialysis occurs in a hemisphere($600{\mu}m$ in mediolateral direction and $100{\mu}m$ in opposite side of the dialysis probe) around the opening rather than in a spherical shaped configuration which is typical of most commercially available probe designs. 3. Glutamate, taurine and glycine were present in the highest concentration in the dialysate sample obtained before treatment with veratridine, whereas, aspartate and GABA were present in the lowest concentration. 4. The concentration of all 5 amino acids increased significantly following $75{\mu}m$ veratridine perfusion into lateral ventrocaudal PAG. 5. There was no significant difference between basal and peak amino acid concentrations according to window sizes. 6. Morphine had no effect on baseline concentrations of amino acids in dialysates obtained from the lateral PAG as compared to saline treated controls. However, following veratridine treatment, morphine selectively affected GABA release in the lateral ventrocaudal PAG as compared to saline treated controls. These results suggest that GABAergic interneurons in the PAG are inhibited by opioids. Therefore, endogenous enkephalins or endorphins may directly inhibit intrinsic GABAergic intemeurons and block their tonic inhibition of PAG-NMR projection neurons. Moreover, new designed probes demonstrate improved efficiency and accuracy in collecting samples as compared to commercial types of microdialysis probes.

• Journal of the Korea Society of Computer and Information
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• v.18 no.12
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• pp.1-9
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• 2013

Even though the multiple pages TLB are effective in improving the performance, a conventional method with OS support cannot utilize multiple page sizes in user application. Thus, we propose a new multiple-TLB structure supporting multiple page sizes for high performance and low power consumption without any operating system support. The proposed TLB is organised as two parts of a S-TLB(Small TLB) with a small page size and a L-TLB(Large TLB) with a large page size. Both are designed as fully associative bank structures. The S-TLB stores small pages are evicted from the L-TLB, and the L-TLB stores large pages including a small page generated by the CPU. Each one bank module of S-TLB and L-TLB can be selectively accessed base on particular one and two bits of the virtual address generated from CPU, respectively. Energy savings are achieved by reducing the number of entries accessed at a time. Also, this paper proposed the simple 1-bit LRU policy to improve the performance. The proposed LRU policy can present recently referenced block by using an additional one bit of each entry on TLBs. This method can simply select a least recently used page from the L-TLB. According to the simulation results, the proposed TLB can reduce Energy * Delay by about 76%, 57%, and 6% compared with a fully associative TLB, a ARM TLB, and a Dual TLB, respectively.

• Investigative Magnetic Resonance Imaging
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• v.9 no.1
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• pp.43-49
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• 2005

A few studies have shown that the function of fusiform face area is selectively involved in the perception of faces including a race difference. We investigated the neural substrates of the face-selective region called fusiform face area in the ventral occipital-temporal cortex and same-race memory superiority in the fusiform face area by the event-related fMRI. In our fMRI study, subjects (Oriental-Korean) performed the implicit distinction of the race while they consciously made familiar-judgments, regardless of whether they considered a face as Oriental-Korean or European-American. For race distinction as an implicit task, the fusiform face areas (FFA) and the right parahippocampal gyrus had a greater response to the presentation of Oriental-Korean faces than for the European-American faces, but in the conscious race distinction between Oriental-Korean and European-American faces, there was no significant difference observed in the FFA. These results suggest that different activation in the fusiform regions and right parahippocampal gyrus resulting from superiority of same-race memory could have implicitly taken place by the physiological processes of face recognition.

• Journal of Chest Surgery
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• v.36 no.8
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• pp.595-601
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• 2003

Background: It has been known that the most effective treatment method of hyperhidrosis is video-assisted thoracoscopic sympathetic nerve block. Postoperative compensatory hyperhidrosis and anhidrosis are major factors that decrease the postoperative satisfaction. Although sympathetic rami have been selectively blocked to decrease the complications, technical difficulties and excessive bleeding have prevented the universal application. Material and Method: Three pre-fixative cadavers were dissected before clinical application. Bilateral sympathetic chains were exposed in supine position after the whole anterior chest wall was removed. Second and third sympathetic rami were blocked using clips. After the sympathetic chains including ganglia were removed, we evaluated the extents of rami block. Twenty-five patients were subjected to the clinical application. Surgeries were performed in semi-fowlers position under general anesthesia and bilateral ventilation. 2 mm thoracoscopy and 5 mm trocar were intro-duced through third and fourth intercostal space, respectively. Second and third sympathetic rami were blocked using thoracoscopic clips. The postoperative complications, satisfaction, and compensatory hyperhidrosis rate were evaluated retrospectively. Result: Sympathetic rami were completely blocked in cadaver dissection study Hyper-hidrosis symptom was improved in all patients without operative complication. Operative time was shorter than that of traditional ramicotomy. All patients, except four, were satisfied with postoperative palmar hyperhidrosis. Com-pensatory hyperhidrosis was more severely happened in fifteen patients (60%). The remaining six patients had no complaint. Two patients had a minimal degree of gustatory hyperhidrosis. Conclusion: This operative method had shorter operative time and less complication rate, compared with traditional ramicotomy Operative success rate was similar to the traditional syrnpathicotorny; lower extent and occurrence rate of compensatory hyperhidrosis. The thoracic sympathetic rami clipping was suggested as an alternative method for treatment of palmar hyperhidrosis.