• Journal of Sensor Science and Technology
• /
• v.1 no.2
• /
• pp.147-154
• /
• 1992

This paper describes the design of implantable 8-channel telemetering system to get physiological signals. The internal circuits of this system are designed not only to achieve as small size and low power dissipation as possible, but also to enable continuous measurement of physiological signals. Its main functions are to enable continuous measurement of physiological signals and to accomplish on-off power switching of an implantable battery by receiving appropriate command signals from an external circuit. To integrate implantable biotelemetry system, we performed layout of internal system using Lambda based $2{\mu}m$ n-well design rules. This system, used together with appropriate sensors, is expected to be capable of measuring and transmitting such significant parameters as pressure, pH, and temperature.

• Journal of Sensor Science and Technology
• /
• v.5 no.1
• /
• pp.43-50
• /
• 1996

This paper presents a manufacture of the multiple subjects biotelemetry system using custom CMOS IC fabricated $1.5{\mu}m$ n-well process technology. The implantable circuits of the system except sensor interface circuits including FM transmitter are fabricated on a single chip with the sire of $4{\times}4mm^{2}$. It is possible to assemble the implantable system in a hybrid package as small as $3{\times}3{\times}2.5cm$ by using this chip, It's main function is to enable continuous measurement simultaneously up to 7-channel physiological signals from the selected one among 8 subjects. Another features of this system are to enable continuous measurement of physiological signals, and to accomplish ON/OFF switching of an implanted battery by subject selection signal with command signal from the external circuit. If this system is coupled with another appropriate sensors in medical field, various physiological parameters such as pressure, pH and temperature are to be measured effectively in the near future.

• Applied Microscopy
• /
• v.37 no.3
• /
• pp.175-183
• /
• 2007

The Drosophila retinal cell is widely used to study cell development and cell signaling processes. In the past decades, conventional chemical fixation had been used to study the structure of retinal cells in Droscphila. Rapid freezing methods are superior to chemical fixation methods due to their fixation speed. Some Drosophila tissues, such as the eyes, should not be freezed due to their surrounding cuticle layer. Therefore, in the case of the Drosophila retina, the benefits of high pressure freezing and freeze substitution (HPF-FS) had not been verified. In this study, a retinal cell from Drosophila melanogaster had been studied by using the HPF-FS method. Compared to chemical fixation, the preservation of the cytoplasm in the HPF-FS sample was improved on the whole. The HPF-FS cell membranes were smoother than that of chemical fixation. In addition, HPF-FS preserved the mitochondria structures very well. These results of the present study suggest that HPF-FS is superior to other fixation methods for the preservation of the retinal cell structure.

• Journal of Sensor Science and Technology
• /
• v.16 no.6
• /
• pp.441-448
• /
• 2007

In this study, the fiber-optic fluoro-immunosensor was designed to detect foodborne pathogens. The fabricated system is composed of the multimode optical fiber on which antibodies are immobilized. Then, a sandwich immunoassay is applied to the fabricated the fiber-optic fluoro-immunosensor. In the "sandwich" binding format, a primary or "capture" antibody is immobilized on the core surface of the multimode optical fiber and a secondary or named as "tracer" antibody is added to the bulk solution. A tracer is labeled FITC (fluorescein isothiocyanate; ${\lambda}ex$=492 nm, ${\lambda}em$= 520 nm). Different concentrations of antigens are tested in different fibers. The detection limit of the fabricated system is 5.08×103 cfu/ml for Vibrio antigen and $0.1{\mu}g/ml$, $0.05{\mu}g/ml$ in non-labeled monolayer phosphate buffered saline (NMP), non-labeled monolayer carbonate bicarbonate buffer (NMC), respectively.

• Journal of the Korean Chemical Society
• /
• v.41 no.11
• /
• pp.590-593
• /
• 1997

Square-wave anodic stripping voltammetry was applied to the germanium(IV)- Morin complex in 0.5 M sulfuric acid as a supporting electrolyte. The peak potential appeared at - 0.606 V vs. Ag/AgCl. Effects of sulfuric acid concentration, Morin concentration, accumulation potential, and accumulation time on the stripping peak current for the complex of germanium(IV)-Morin were studied. Interferences by other metal cations that affect on stripping peak current were also investigated. The detection limit was found to be $3.76{\times}10^{-7}M(27 {\mu}g/L)$ for germanium(IV) using 60 seconds of accumulation time. The relative standard deviation (n=8) for 0.4 mg/L($5.5{\times}10^{-6}$ M) germanium(IV) was 3.2%.

• International Journal of Oral Biology
• /
• v.42 no.1
• /
• pp.33-38
• /
• 2017

Background: Periodontitis is an inflammatory disease characterized by the breakdown of tooth-supporting tissues, leading to tooth loss. Aggregatibacter actinomycetemcomitans are major etiologic bacterium causing aggressive periodontitis. Ursodeoxycholic acid (UDCA), a hydrophilic gall bladder acid, has been used as an effective drug for various diseases related to immunity. The aim of this study was to investigate the effect of UDCA on the inflammatory response induced by A. actinomycetemcomitans. Methods: A human acute monocytic leukemia cell line (THP-1) was differentiated to macrophage- like cells by treatment with phorbol 12-mystristate 13-acetate (PMA) and used for all experiments. The cytotoxic effect of UDCA was examined by MTT assay. THP-1 cells were pretreated with UDCA for 30 min before A. actinomycetemcomitans infection and the culture supernatant was analyzed for various cytokine production by ELISA. The effect of UDCA on bacterial growth was examined by measuring optical densities using a spectrophotometer. Results: UDCA showed no cytotoxic effect on THP-1 cells, up to $80{\mu}M$ Ed highlight: Please confirm technical meaning. UDCA pretreatment inhibited the A. actinomycetemcomitans-induced $IL-1{\beta}$, $TNF-{\alpha}$, and IL-17A secretion in a dose-dependent manner. UDCA also inhibited IL-21 production at $60{\mu}M$. The production of IL-12 and IL-4 was not influenced by A. actinomycetemcomitans infection. Conclusion: These findings indicate that UDCA inhibits the production of inflammatory cytokines involved in innate and Th17 immune responses in A. actinomycetemcomitans-infected THP-1- derived macrophages, which suggests its possible use for the control of aggressive periodontitis.

• Journal of Sensor Science and Technology
• /
• v.2 no.1
• /
• pp.19-27
• /
• 1993

Capacitive pressure sensor for low pressure measurements has been fabricated by using $n^{+}$ epitaxial layer electrochemical etching stop and glass-to-silicon electrostatic bonding technique. The sensor had hybrid configuration of a sensor chip, which consists of sensor capacitor and reference capacitor, and two output signal detection IC chips. A fabricated sensor, with a $1.0{\times}1.0 mm^{2}$ square size and a $10{\mu}m$ thick flat diaphragm, showed a 7.1 pF zero pressure capacitance, and 5.2 % F.S, sensitivity in 10 KPa pressure range. By using a capacitance to voltage converter, the thermal zero shift of 0.051 %F.S./$^{\circ}C$ and the thermal sensitivity shift of 0.12 %F.S./$^{\circ}C$ for temperature range of $5{\sim}45^{\circ}C$ were obtained.

• Korean Journal of Materials Research
• /
• v.16 no.10
• /
• pp.606-613
• /
• 2006

This study was purposed to evaluate the influence of anodically oxidized film on titanium (Ti) onto MG-63 osteoblast-like cell attachment and activity. Only scratch lines created by polishing were seen in ASR and ANO-1 groups. About $1.5{\mu}m$-thick homogeneous oxide film which has pores of about $0.5{\mu}m$ diameter were formed in ANO-12. The crystalline structure of the oxide films formed by anodization in phosphoric acid electrolyte was $TiP_2O_7$. The total protein amounts of ANO-1 and ANO-12 groups showed higher values of maximum protein amount than that of AS-R group. At 3 days of incubation, total protein amount showed higher value in ANO-2 when comparing to that of AS-R (p<0.05). Based on the results of ALPase activity test, the degree of MG-63 cell differentiation for initial mineralization matrix formation was similar. For all the test groups after 1 day of incubation, MG-63 cells grew healthily in mono-layer with dendritic extensions. After incubation for 3 days, the specimen surfaces were covered more densely by cells, and numerous micro filaments were extruding to the extracellular matrix.

• Childhood Kidney Diseases
• /
• v.17 no.2
• /
• pp.132-136
• /
• 2013

Parainfluenza virus infection is one of the causes of fatal rhabdomyolysis. Rhabdomyolysis can be aggravated by mitochondrial fatty acid ${\beta}$-oxidation disorders during prolonged periods of fasting. Moreover, in patients with late-onset isovaleric acidemia, hyperammonemia may occur following catabolic stress. In the present report, we describe a case of a 4-year-old boy with parainfluenza virus infection and late-onset isovaleric acidemia that rapidly progressed to coma, seizures, and cardiorespiratory collapse. His serum ammonia and creatinine kinase (CK) levels were $385{\mu}Mol/L$ and 23,707 IU/L, respectively. Continuous renal replacement therapy (CRRT) was initiated using continuous venovenous hemodiafiltration, after which the ammonia and CK levels returned to normal. Thus, we recommend the immediate initiation of CRRT in the management of patients with life-threatening rhabdomyolysis and hyperammonemia.

• Korean Journal of Acupuncture
• /
• v.22 no.1
• /
• pp.85-93
• /
• 2005

목적 : 본 연구는 봉독 약침액이 BV2 microglial cell에서 LPS로 유발된 염증반응에 대한 억제효과를 관찰하고자 하였다. 방법 : 봉독 약침액의 항염증작용을 관찰하기 위하여 BV2 microglial cell에 봉독약침액을 1시간전에 농도별$(0.1,\;1,\;100\;{\mu}g/ml)$로 전처치한 후 LPS $(5\;{\mu}g/ml)$로 24시간 동안 처리하여 RT-PCR, western blot, $PGE_2$, assay, NO synthesis assay등의 방법으로 관찰하였다. 결과 : LPS 염증유발에 의해서 BV2 microglial cell에서 COX-2 및 NOS 발현이 증가하였고, 이 러한 증가는 prostaglandin E2 및 NO 합성을 증가시켰다. 이에 반하여 봉독약침액으로 전처치한 군에서는 COX-2 및 NOS 발현을 억제시켜 결과적으로 prostaglandin 합성 및 NO 합성을 억제시킴을 확인할 수 있었다. 또한 LPS 염증유발에 의해서 활성화된 NF-kB의 발현을 억제 시켰다. 결론 : 봉독약침 액은 LPS 염증유발에 의해서 증가된 prostaglandin E2 및 NO 합성을 억제시킴으로써 여러 가지 염종질환의 치료에 유효한 효과가 있을 것으로 사려 된다.