• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.8
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• pp.737-743
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• 2004

A fixed-tuned SIS(Superconductor-Insulator-Superconductor) mixer across 120∼180 GHz band has been developed. This mixer employs an SIS chip fabricated by Nobeyama radio observatory which consists of a series array of 6 Nb/Al-Al$_2$O$_3$/Nb junctions in a microstrip line on a fused quartz substrate. The SIS chip is placed at the center of the half-height waveguide mixer mount to have a good incoming signal coupling over the whole frequency band. No mechanical tuner was used in the SIS mixer and the RF signal and local oscillator power are injected to the mixer via a cooled cross-guide coupler. In order to prevent the IF signal loss, the If output impedance of the SIS mixer was matched to the 50 $\Omega$ input impedance of the IF chain. Measured double sideband noise temperatures of a receiver using the SIS mixer are 32∼131 K over 120∼180 GHz band. The developed SIS mixer is now in use for radio astronomical observations on the TRAO 14 m radio telescope.

• Polymer(Korea)
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• v.32 no.3
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• pp.199-205
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• 2008

In this study, we fabricated poly (lactide-co-glycolide) (PLGA) scaffold modified with small intestinal submucosa (SIS) as a drug delivery matrix of bioactive molecules. SIS derived from the submucosa layer of porcine intestine has been widely used as biomaterial because of low immune response. PLGA scaffold was prepared by the method of solvent casting/salt leaching. Novel composite scaffolds of SIS/PLGA were manufactured by simple immersion method of PLGA scaffold in SIS solution under vacuum. SEM observation shows that PLGA and SIS/PLGA scaffolds have interconnective and open pores. Especially, SIS/PLGA scaffold showed that micro-sponge of SIS with interconnected pore structures were formed in the pores of PLGA scaffold. In order to assay release profile of proteins, we manufactured FITC conjugated BSA loaded PLGA and SIS/PLGA scaffold. And the release amount was identified by fluorescence intensity using the fluorescence spectrophotometer. The initial burst of BSA containing SIS/PLGA scaffolds was lower than that of PLGA scaffolds resulting in constant release. And release of BSA in SIS/PLGA scaffold was fast and incremental because of the increased content of BSA. In conclusion, we confirmed that penetrated SIS solution prevented the initial burst of BSA and PLGA modified with SIS scaffold is useful as protein carriers with controlled release pattern.

• Physical Therapy Korea
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• v.15 no.1
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• pp.12-19
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• 2008

The purpose of this study was to determine the relationship between activities of daily living and health-related quality of life in ambulatory stroke patients. This was a cross-sectional survey study of 60 patients who had survived one year or more after a stroke in community. Activities of daily living were assessed using the Functional Independence Measure (FlM) and health-related quality of life using the Stroke Impact Scale (SIS). The association between FIM and SIS was examined using Pearson' s correlation. The FIM score was higher than the SIS score. Most domains of FIM exhibited a high rate (45-85%) of ceiling effects. However, only the communication and memory domain of SIS exhibited of ceiling effects. The correlation coefficients were .835 (p<.01) for FIM-motor vs. SIS-ADL, .257 (p<,05) for FIM-motor vs. SIS-communication, .596 (p<.01) for FIM-motor vs. SIS-social participation, .635 (p<.01) for FIM-cognition vs. SIS-memory, .369 (p<.01) for FIM-cognition vs. SIS-ADL, and .289 (p<.05) for FlM-cognition vs. SIS-social participation. In conclusion, the correlation between FIM-motor and SIS-social participation was higher than that of FlM-cognition and SIS-social participation. The domains of emotion and hand function of SIS showed no correlation coefficients with FIM-total. To examine the activities of daily living and the quality of life in ambulatory stroke patients in community, it is necessary to use both the FIM and SIS.

• Polymer(Korea)
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• v.32 no.5
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• pp.415-420
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• 2008

The porcine small intestinal submucosa (SIS) without immunorejection responses and hyalunonic acid (HA) can be used as biomaterials. In this study, we tried to design and characterize novel sponge. SIS- HA sponge was prepared by freeze-drying after addition 1wt% HA solution into fabricated SIS sponge. Sponge was crosslinked with 1-ethyl-(3-3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) solution with 100mM concentration for 24 hrs and lyophilized. SIS-HA sponge was characterized by scanning electron microscopy and fourier transform infrared spectrometer. And water absorption ability of sponge was evaluated. We seeded NIH/3T3 cells in SIS-HA sponge and cellular attachment was assayed by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltertazolium-bromide (MTT) test. We demonstrated presence of HA in SIS-HA sponge from C-O functional group observed by the FT-IR analysis. Moreover, we confirmed low cytotoxicity and high cell viability of the SIS-HA sponges. Therefore, we could expect that SIS- HA scaffolds are applicable for the tissue regeneration.

• Polymer(Korea)
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• v.30 no.3
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• pp.259-265
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• 2006

Small intestinal submucosa (SIS) consists of some growth factors which can stimulate cell activity, and PVA has been widely utilized in the area of wound dressing as hydrogel which is easy to be removed from wounds. In this study, native SIS sheets were coated with PVA by immersing them into 2, 4, and 10 wt% of PVA solution and then lyophilized on two type of molds to endow the prepared wound dressing with easy removal property from wounds. The mechanical properties were examined through tensile test. Moreover, enzymatic degradation, water uptake, and in vitro test were carried out to characterize the prepared SIS sheets. The tensile strength of the SIS sheets coated with PVA (PVA-SIS) were decreased, whereas the elongation were increased. Degradation ratio of the PVA-SIS sheets was decreased compare to native SIS. Water uptake ability was improved at 2 and 4 wt% of PVA. The degree of fibroblast attachment was lower than the native SIS sheets. In conclusion, this study suggests that the PVA coated SIS sheets have a potential for the applications of wound dressing and biodegradable injectable materials.

• Polymer(Korea)
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• v.28 no.6
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• pp.478-486
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• 2004

Small intestinal submucosa (SIS) is consisted with collagen and glycosaminoglycan as well as some growth factors which can stimulate cell activity. Recently, it has been recognized that SIS has been successfully examined in the bio-medical application as biomaterials without xenograft immune-rejection response. We prepared native SIS sheets and acid treated SIS sheets by acetic acid with 1 or 5-layered sheets, respectively. The water uptake ability of native and acid treated SIS sheets was examined to evaluate the possibility as wound dressings. Morphologies of SIS sheets were characterized by SEM and the effects of various buffer solutions and different pH solutions on the water uptake ability were observed for 16 days. We observed that the acid treated SIS sheets had higher water uptake ability than native SIS sheets. Also, the water uptake ability of these was slightly higher in various buffers than distilled water. In conclusion, this study suggests that native and acid treated SIS sheets could be useful for the applications of wound dressing and biodegradable injectable materials.

• Macromolecular Research
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• v.10 no.3
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• pp.158-167
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• 2002

In order to endow with new bioactive functionality from small intestine submucosa (SIS) powder as natural source to poly (L-lactide) (PLA) and poly (lactide-co-glycolide) (PLGA) synthetic biodegradable polymer, porous SIS/PLA and SIS/PLGA as natural/synthetic composite scaffolds were prepared by means of the solvent casting/salt leaching methods for the possibility of the application of tissue engineered bone and cartilage. A uniform distribution of good interconnected pores from the surface to core region was observed the pore size of 40~500 ${\mu}{\textrm}{m}$ independent with SIS amount using the solvent casting/salt leaching method. Porosities, specific pore areas as well as pore size distribution also were almost same. After the fabrication of SIS/PLA hybrid scaffolds, the wetting properties was greatly enhanced resulting in more uniform cell seeding and distribution. Five groups as PGA non-woven mesh without glutaraldehyde (GA) treatment, PLA scaffold without or with GA treatment, and SIS/PLA (Code No.3 ; 1 : 12 of salt content, (0.4 : 1 of SIS content, and 144 ${\mu}{\textrm}{m}$ of median pore size) without or with GA treatment were implanted into the back of nude mouse to observe the effect of SIS on the induction of cells proliferation by hematoxylin and eosin, and von Kossa staining for 8 weeks. It was observed that the effect of SIS/PLA scaffolds with GA treatment on bone induction are stronger than PLA scaffolds, that is to say, in the order of PLA/SIS scaffolds with GA treatment > PLA/SIS scaffolds without GA treatment > PGA nonwoven > PLA scaffolds only with GA treatment = PLA scaffolds only without GA treatment for the osteoinduction activity. The possible explanations are (1) many kinds of secreted, circulating, and extracellular matrix-bound growth factors from SIS to significantly affect critical processes of tissue development and differentiation, (2) the exposure of SIS to GA resulted in significantly calcification, and (3) peri-implant fibrosis due to covalent bonding between collagen molecule by crosslinking reaction. In conclusion, it seems that SIS plays an important role for bone induction in SIS/PLA scaffolds for the application of tissue engineering area.

• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.690-697
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• 2017

In this study, styrene-isoprene-styrene (SIS)-styrene-butadiene-styrene (SBS) modified asphalt was prepared for waterproof-sheet to measure its properties including softening point, penetration, low temperature flexibility, viscosity and adhesion. Then the properties of SIS-SBS modified asphalt imparted with self-healing were optimized to seek for optimal compositions of SIS and SBS versus asphalt according to response surface methodology (RSM). As the content of SBS or SIS was increased, both properties of softening point and viscosity, measured at high temperature, were increased with a statistical significance. However, the increments of softening point and viscosity per unit content of SBS added, were observed to be greater than those per unit content of SIS added, respectively. It was due to the difference of thermal properties of SBS and SIS at high temperature that the cross-linking degree of SBS was increased by gelation accompanied with the increase of viscosity, while chain-entanglement of SIS was relatively reduced owing to a chain scission of poly(isoprene) blocks causing the decrease of viscosity. To the contrary, SIS-SBS modified asphalt showed a behavior of the least elasticity resulting in both the maximum of penetration and adhesion, measured at room temperature, as well as the lowest low temperature flexibility at the composition of SIS, 4 g and SBS, 8.5 g based on asphalt, 63 g.

• The Korean Journal of Pain
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• v.33 no.1
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• pp.60-65
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• 2020

Background: Anatomic changes in the acromion have been considered a main cause of shoulder impingement syndrome (SIS). To evaluate the relationship between SIS and the acromion process, we devised a new morphological parameter called the acromion process cross-sectional area (APA). We hypothesized that the APA could be an important morphologic diagnostic parameter in SIS. Methods: We collected APA data from 95 patients with SIS and 126 control subjects who underwent shoulder magnetic resonance imaging (MRI). Then we measured the maximal cross-sectional area of the bone margin of the acromion process on MRI scans. Results: The mean of APAs were 136.50 ± 21.75 ㎟ in the male control group and 202.91 ± 31.78 ㎟ in the male SIS group; SIS patients had significantly greater APAs (P < 0.001). The average of APAs were 105.38 ± 19.07 ㎟ in the female control group and 147.62 ± 22.90 ㎟ in the female SIS group, and the SIS patients had significantly greater APAs (P < 0.001). The optimal APA cut-off in the male group was 165.14 ㎟ with 90.2% sensitivity, 91.4% specificity, and an area under the curve (AUC) of 0.968. In the female group, the optimal cut-off was 122.50 ㎟ with 85.2% sensitivity, 84.9% specificity, and an AUC of 0.928. Conclusions: The newly devised APA is a sensitive parameter for assessing SIS; greater APA is associated with a higher possibility of SIS. We think that this result will be helpful for the diagnosis of SIS.

• Polymer(Korea)
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• v.32 no.1
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• pp.49-55
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• 2008

It is recognized that Schwann cells (SC) are essential for peripheral nerve development and regeneration. SIS (small intestinal submucosa) consists of some growth factors which can stimulate cell activity without immune rejection responges. SCs were harvested from the femurs and tibias of female Fischer rat and then suspended with $2{\times}10^6$ cell/sponge in SIS sponge. Fischer rat received an implant consisting of the SCs and the SIS sponge at the place of a 5 mm gap created by the sciatic nerve resection. Thin sections were stained with H &E staining and immunostaining of S-100, GFAP and NF after 1, 2, and 4 weeks. It was observed that the effects of the SIS sponge with SCs on neuroinduction(Group II, with scaffold & cell) are strong as much as uninjured model(Control I), and significantly stronger than SIS sponge model (Group 1, with scaffold only) and blank model (Control II). In conclusion, these results suggest that SIS sponge filled with SCs may have an important role for peripheral nerve regeneration of tissue engineering.