• The Journal of Korean Physical Therapy
• /
• v.6 no.1
• /
• pp.5-15
• /
• 1994

The purpose of this study was to examine the effect of electroanalgeia and $\beta-endorphin$ action by acupuncture-like (Lof/Hil) transcutaneous electrical nerve stimulation (TENS) applied to acupuncture points. Twelve healthy adult male aged between 19 ann 25 were randomly assigned to TENS group (n=6) and naloxone group (n=6). Subjects of both groups were strongly stimulated TENS with 4 pps and $200{\mu}s$ for 30 minutes on the LI 3 and LI 10 meridian points of dominant am. Naloxone group was injected naloxone hydrochloride before TENS application. The experimental pain threshold was measured by chronaxie meter CX-2 on the distal end of radius just before and after TENS application. The levels of plasma $\beta-endorphin$ and ACTH. serum cortisol and urinary 17-OHCS were analyzed by radioimmunoassay (RIA) kits before and after TENS application. In TENS group, there was a significant increase of experimental pain threshold (p<0.01), plasma $\beta-endorphin$ level (p<0.05), serum cortisol level (p<0,001) and urinary 17-OHCS levels (p<0.05) after TENS application. The plasma ACTH level was not significantly increased, but it showed an increasing tendency. In naloxone group, although there was a decreasing trend, ACTH and cortisol level did not show a significant change, but $\beta-endorphin$ and 17-OHCS level were significantly decreased (p<0.01). The result of this study stewed that acupuncture-like TENS induced analgesic effect, such that the levels of plasma $\beta-endorphin$, plasma ACTH, serum cortisol and urinary 17-OHCS were concomitantly increased with experimental pain threshold. It is suggested that the analgesic mechanism of the acupuncture-like TENS probably related to endogenous opioid component such as $\beta-endorphin$.

• The Journal of Korean Physical Therapy
• /
• v.6 no.1
• /
• pp.85-93
• /
• 1994

The purposes of this study were 1) to examine the effects of microcurrent electrical neuromuscular stimulation 2) to compare surface electrode with needle electrode at somatic acupuncture points on experimental pain threshold measured at the distal end of the radius 3) to determine the changes in effect over time. A total of sixty healthy adult male and female subjects were assigned randomly to one of two experimental group or to a control group. Group 1(n=20) received MENS(Microcurrent Electrical Neuromuscular Stimulation) with surface electrode. Group 2(n=20) received HENS with needle electrode. Group 3(n=20) received no MENS. It measured experimental pain threshold at the wrist on pretreatment, 0 min after treatment. 15 min after treatment, 30 min after treatment in two experimental group. The results were as follows: 1. Experimental pain thresholds were higher in males than females(P<0.01). 2. Only the experimental group exhibited a significant increased in pain threshold after MENS treatment(P<0.05). 3. Surface electrode group increased significant pain threshold 0 min, 15 min after treatment, but greatly decrease 30 min after treatment. 4. Needle electrode group increased significant pain threshold 0 min, 15 min after treatment, but decrease 30 min after treatment. The results suggest that MENS applied to appropriate somatic acupuncture point can increase pain threshold. Further research is needed to assess the effects of greatly variety intensity of MENS of pain sufferes.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.36 no.11
• /
• pp.1405-1411
• /
• 2012

Remote handling manipulators are widely used for performing hazardous tasks, and it is essential to ensure the reliable performance of such systems. Toward this end, tendon-driven mechanisms are adopted in such systems to reduce the weight of the distal parts of the manipulator while maintaining the handling performance. In this study, several approaches for the design of a gripper system for a tendon-driven remote handling system are introduced. Basically, this gripper has an underactuated spring mechanism that is combined with a slave manipulator triggered by a master operator. Based on the requirements under the specified tendon-driven mechanism, the connecting position of the spring system on the gripper mechanism and kinematic influence coefficient (KIC) analysis are performed. As a result, a suitable combination of components for the proper design of the target system is presented and verified.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.2
• /
• pp.148-155
• /
• 2008

The aim of the study is to interpret the distribution of occlusal force by 3-dimensional finite element analysis of ISP(Implant Supported Prosthesis) supported by minimum number of implant to restore the edentulous patients. For this study, the Astra Tech implant system is used. Geometric modeling for 6 and 4 fixture ISP group is performed with respect to the bone, implant and one piece superstructure, respectively. Implants are arbitrarily placed according to the anatomical limit of lower jaw and for the favorable distribution of occlusal force, which is applied at the end of cantilever extension of ISP with 30mm. Element type is tetrahedral for finite element model and the typical mechanical properties, Young's modulus and Poisson's ratio of each material, cortical, cancellous bone and implant material are utilized for the finite element analysis. From this study, we can see the distribution of equivalent stress equal to real situation and speculate the difference in the stress distribution in the whole model and at each implant fixture, From the analysis, the area of maximum stress is distributed on distal contact area between bone and fixture in the crestal bone. The maximum stress is 53MPa at the 0.2mm area from the bone-implant interface in the maximum side for 300N load condition for 4 fixture case, which is slightly less than the stress calculated from allowable strain. This stress has not been deduced to directly cause the loss of crestal bone around implant fixture, but the stress can be much reduced as the old peoples may have lower chewing force. Thus, clinical trial may be performed with this treatment protocol to use 4 fixtured ISP for old patients.

• Archives of Plastic Surgery
• /
• v.32 no.4
• /
• pp.485-490
• /
• 2005

Fingertip is the end of tactile organ and the part of hand most frequently injured. Fingertip injuries should be evaluated on an individual basis considering patient's overall physical condition, medical history, etiology, time of injury, and anticipated future hand use, and accordingly one of various methods of reconstruction should be selected. Complications after the reconstruction of fingertip injuries have been reported as pain, hypersensitivity, numbness, distal paresthesia, cold intolerance, and atrophy. From January to December 2002, dermofat grafts were performed on 15 patients to correct painful fingertips after injury. The thickness of the soft tissue of fingertip was measured both preoperatively and postoperatively with simple X-ray. To evaluate the improvement of pain, visual analogue scale(VAS) was used through the direct interview with patients. The average of postoperative follow-up period was 10.9 months. The average of increased soft tissue thickness ratio was 88.4%(2.3mm to 3.8mm). The average of preoperative VAS was 7.6, and postoperative VAS was 3. Dermofat graft on fingertip needs a further long-term follow-up study for the absorption ratio of dermofat, however, this procedure is simple and could be done under local anesthesia, and would be a useful alternative procedure to correct painful fingertips with the soft tissue atrophy after injury.

• Journal of Biomedical Engineering Research
• /
• v.28 no.1
• /
• pp.84-94
• /
• 2007

In order to collect information on local distribution of conductivity and permittivity underneath a scan probe, we developed a multi-frequency trans-admittance scanner (TAS). Applying a sinusoidal voltage with variable frequency on a chosen distal part of a human body, we measure exit currents from 320 grounded electrodes placed on a chosen surface of the subject. The electrodes are packaged inside a small and light scan probe. The system includes one voltage source and 17 digital ammeters. Front-end of each ammeter is a current-to-voltage converter with virtual grounding of a chosen electrode. The rest of the ammeter is a voltmeter performing digital phase-sensitive demodulation. Using resistor loads, we calibrate the system including the scan probe to compensate frequency-dependent variability of current measurements and also inter-channel variability among multiple. We found that SNR of each ammeter is about 85dB and the minimal measurable current is 5nA. Using saline phantoms with objects made from TX-151, we verified the performance of the lesion estimation algorithm. The error rate of the depth estimation was about 19.7%. For the size estimate, the error rate was about 15.3%. The results suggest improvement in lesion estimation algorithm based on multi-frequency trans-admittance data.

• Journal of Biomedical Engineering Research
• /
• v.29 no.6
• /
• pp.451-456
• /
• 2008

Total knee arthroplasty(TKA) using computer-assisted navigation has been increased in order to improve the accuracy of femoral and tibial components implantation. Recently, a few clinical studies have reported on the femoral stress fracture after TKA using computer-assisted navigation. The purpose of this study is to investigate the stress concentration around the femoral pin-hole for different pin-hole diameter, the modes of pin penetration by finite element analysis to understand the effects of pin-hole parameters on femoral stress fracture risk. A three-dimensional finite element model of a male femur was reconstructed from 1 mm thick computed tomography(CT) images. The bone was rigidly fixed to a 25 mm above the distal end and 1500 N of axial compressive force and 12 Nm of axial torsion were applied at the femoral head. For all cases, transcortical pin penetration mode showed the highest stress fracture risk and unicortical pin penetration mode showed the lowest stress concentration. Pin-hole diameter increased the stress concentration, but pin number did not increase the stress dramatically. The results of this study provided a biomechanical guideline for pin-hole fracture risk of the computer navigated TKA.

• Journal of Microbiology and Biotechnology
• /
• v.11 no.6
• /
• pp.1046-1054
• /
• 2001

Bioleaching is the process in which insoluble metal sulfide is oxidized by specialized iron- and/or sulfur-oxidizing lithotrophic bacteria in acidic, metal-rich environments. Most of these processes are carried out by the genus Thiobacillus. Three novel Thiobacillus strains (Thiobacillus thiooxidans AZ11, Thiobacillus thiooxidans MET, and thiobacillus thiooxidans TAS) associated with bioleaching have been isolated from soil and sludge (Korean patent No. 1999-0073060 for T. thiooxidans AZ11, Korean patent No. 1999-0005798 for T. thiooxidans MET, and Korean patent No. 1999-0073059 for T. thiooxidans TAS). A partial sequence of 16S ribosomal RNA gene (16S rDNA) and the entire sequence of 16S/23S intergenic spacer region (ISR) were determined in the three above novel strains and in Thiobacillus ferrooxidans ATCC19859 as a reference strain. When phylogenetic analysis was performed based on G+C contents and sequence alignments, T. ferroxidans ATCC19859 was found to be closely related to previously registered T. ferrooxidans strains in a monophyletic manner, while the three novel T. thiooxidans strains were classified in a paraphyletic manner. Close examination on the base composition of 16S/23S ISR revealed that the 5\` part (nucleotide residues 21-200) was specific for the genus Thiobacillus. On the other end, the 3\` part (nucleotide residues 201-520) showed specificity in T. ferrooxidans strains, but not in T. thiooxidans strains. These results suggest that the proximal and distal halves of 16S/23S could be used as a genetic marker for the identification of the genus Thiobacillus and the species T. ferrooxidans, respectively.

• Journal of the Korean Arthroscopy Society
• /
• v.4 no.1
• /
• pp.67-70
• /
• 2000

Osgood-Schlatter's disease is generally treated conservatively. However, surgical treatment is necessary for some patients with recurrent or persistent pain that does not respond to conservative treatment. Most authors recommend the excision of the loose ossicles present around the distal end of the patellar tendon. The authors report the technique of arthroscopic removal of the ossicles for Osgood-Schaltter's disease instead of the conventional technique through the incision at the tibial tuberosity. The advantages of this technique are less damage to the patellar tendon, early postoperative recovery, making no incisional scar in front of the tuberosity which causes the scar discomfort in kneeling, and more cosmetic result.

• Proceedings of the Korean Society of Medical Physics Conference
• /
• 2002.09a
• /
• pp.90-93
• /
• 2002

In particle radiotherapy, a shape of the beam to conform the irradiation field is statically defined by the compensator, collimator and potal devices at the outside of the patient body. However the target such as lung or liver cancer moves along with respiration. This increases the irradiated volume of normal tissue. Prior discussions about organ motions along with respiration have been mainly focused on inferior-superior movement that was usually perpendicular to beam axis. On the other hand, the change of the target depth along the beam axis is very important especially in particle radiotherapy, because the range end of beam (Bragg peak) is so sharp as to be matched to distal edge of the target. In treatment planning, the range of the particle beam inside the body is calculated using a calibration curve relating CT number and water equivalent path length (WEL) to correct the inhomogeneities of tissues. The variation in CT number along the beam path would cause the uncertainties of range calculation at treatment planning for particle radiotherapy. To estimate the uncertainties of the range calculation associated with patient breathing, we proposed the method using sequential CT images with respiration waveform, and analyzed organ motions and WELs at patients that had lung or liver cancer. The variation of the depth along the beam path was presented in WEL rather than geometrical length. In analyzed cases, WELs around the diaphragm were remarkably changed depending on the respiration, and the magnitude of these WEL variations was almost comparable to inferior-superior movement of diaphragm. The variation of WEL around the lung was influenced by heartbeat.