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1.
Int J Med Robot ; 18(5): e2415, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35512295

ABSTRACT

BACKGROUND: The camera of an endoscope is fixed to the device, and the image rotates together with the endoscope. This can lead to visual confusion for the user and incorrect image reading. The problem also occurs with endoscopic robots. Using a master device with the same degrees of freedom as the endoscope to control an endoscopic robot causes visual-motor misorientation, making intuitive control difficult. METHODS: The roll misorientation between the image and master device handle was removed by measuring and correcting for the roll axis displacement of the master device. This enabled intuitive manipulation of the master device. The work speed and number of mistakes were experimentally measured with and without image correction. RESULTS: The tasks were completed significantly faster and more accurately with image orientation correction than without. CONCLUSIONS: The proposed method enables intuitive manipulation of the master device by correcting the image orientation in endoscopic robot control.


Subject(s)
Robotics , Endoscopes , Endoscopy/methods , Equipment Design , Humans
2.
Int J Med Robot ; 18(4): e2402, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35384304

ABSTRACT

BACKGROUND: Commercialised laparoscopic surgical robotic systems require a large operating room and can only be used in large hospitals. If the robotic system is to be used in a small- or medium-sized hospital, the occupied volume must be reduced further. METHODS: In this paper, we propose a bed-mounted system that can be installed in a general operating room. Furthermore, we proposed a novel positioning arm suitable for a bed-mounted surgical robot system. RESULTS: The surgical possibility of the proposed bed-mounted system has been verified. Furthermore, the surgical possibility of the proposed system was confirmed using in vivo animal experiments. CONCLUSIONS: A bed-mounted laparoscopic robotic system and a novel positioning arm was proposed. The study's ultimate goal is to enable robotic surgery in small and medium-sized hospitals by introducing the proposed bed-mounted laparoscopic robot system, allowing many people to receive high-quality medical services.


Subject(s)
Laparoscopy , Robotic Surgical Procedures , Robotics , Animals , Arm , Humans
3.
Int J Med Robot ; 18(3): e2397, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35349215

ABSTRACT

BACKGROUND: Master devices exclusively used for endoscopes with position control are being developed as an isomorphic form of endoscopes. These master devices are difficult to intuitively operate because the movement direction of the endoscopic image and control handle do not match. METHODS: To solve this problem, a master device was developed. Its movement direction is compatible with that of the endoscopic image. It analyzes image movements according to flexible endoscopic ureteroscope movements for each degree of freedom. A driving testbed experiment was conducted that modelled the internal structure of a kidney. RESULTS: The time taken in the experiment was shorter when using the proposed master device than the existing isomorphic master device. The proposed device yielded fewer mistakes. CONCLUSIONS: It was confirmed the proposed device is effective in exclusive use for endoscopes because of its feasibility of position control and movement direction's coinciding with that of the endoscopic image.


Subject(s)
Robotics , Endoscopes , Endoscopy/methods , Equipment Design , Humans
4.
Int J Med Robot ; 18(2): e2357, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34962681

ABSTRACT

BACKGROUND: Control of the joints of robotic surgical instruments is difficult owing to hysteresis, and tendon twisting due to axial rotation of surgical tools also causes hysteresis. Therefore, a new mechanism is needed to prevent tendon twisting. METHODS: Tendon tension and hysteresis change were analysed by observing the movement of the joint depending on whether the tendons twisted for the same input signal. An anti-twist tendon mechanism to prevent twisting was developed. A 3-mm needle driver applied with the proposed mechanism was manufactured. RESULTS: The anti-twist mechanism makes no tension change because of twisting or friction between the tendon and the system, that is, the operating performance was the same regardless of rotation. CONCLUSION: The proposed mechanism has been verified and can be applied to small surgical instruments 3 mm in size. These findings can be applied in the development of instruments for precise surgeries such as microsurgery.


Subject(s)
Robotic Surgical Procedures , Robotics , Humans , Rotation , Surgical Instruments , Tendons/surgery
6.
Mycobiology ; 41(2): 82-5, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23874130

ABSTRACT

The needled leaves of three conifer species were collected in Mt. Taehwa during different seasons of the year. Total 59 isolates and 19 species of endophytic fungi were isolated from the leaves and identified using morphological and molecular characteristics. As a result, Shannon index was different in its host plant; Larix kaempferi had a highest value of species diversity. According to the sampling season, 9 species of 19 species were isolated during fall season. The results suggest that the existing of host plant and sampling season are major factors of distribution of endophytic fungi.

7.
Korean J Anesthesiol ; 64(2): 168-71, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23458916

ABSTRACT

The case of a 33-day-old boy with Pierre Robin syndrome using a Cook® airway exchange catheter in laryngeal mask airway-guided fiberoptic intubation is presented. After induction with sevoflurane, classical reusable laryngeal mask airway (LMA) #1 was inserted and ultrathin fiberoptic bronchoscope (FOB) was passed through. A Cook® airway exchange catheter (1.6 mm ID, 2.7 mm OD) was passed through the LMA under the guidance of the FOB but failed to enter the trachea despite many trials. Then, an endotracheal tube (3.0 mm ID) was mounted on the FOB and railroaded over the FOB. After successful intubation, the Cook® airway exchange catheter was placed in the midtrachea through the lumen of the endotracheal tube. Even though the tracheal tube was accidentally displaced out of the trachea during LMA removal, the endotracheal tube could be easily railroaded over the airway exchange catheter.

8.
Radiat Prot Dosimetry ; 123(4): 540-5, 2007.
Article in English | MEDLINE | ID: mdl-17223642

ABSTRACT

This study is the first nationwide investigation aimed at estimating the patient dose for radiographic examinations in Korea including gastrointestinal studies, computed tomography and mammography. The survey data from 161 hospitals and the dose data from 32 hospitals were analysed. The third quartile entrance surface dose, dose area product (DAP), weighted CT dose index (CTDIw) and mean glandular dose (MGD) were reported. All the estimated doses were less than the stated International Atomic Energy Agency (IAEA) reference levels for radiographic examinations. However, DAPs for the fluoroscopic examinations had higher dose values than the IAEA reference levels. In addition, the CTDIw and MGD were lower than the IAEA reference levels.


Subject(s)
Diagnostic Imaging/standards , Radiation Protection/methods , Radiography/statistics & numerical data , Radiology , Risk Assessment/methods , Body Burden , Humans , Korea/epidemiology , Radiation Dosage , Reference Values , Relative Biological Effectiveness , Risk Factors
9.
Mol Cell Biol ; 22(22): 7721-30, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12391142

ABSTRACT

Heat shock protein 72 (Hsp72) is thought to protect cells against cellular stress. The protective role of Hsp72 was investigated by determining the effect of this protein on the stress-activated protein kinase signaling pathways. Prior exposure of NIH 3T3 cells to mild heat shock (43 degrees C for 20 min) resulted in inhibition of H(2)O(2)-induced activation of apoptosis signal-regulating kinase 1 (ASK1). Overexpression of Hsp72 also inhibited H(2)O(2)-induced activation of ASK1 as well as that of downstream kinases in the p38 mitogen-activated protein kinase (MAPK) signaling cascade. Recombinant Hsp72 bound directly to ASK1 and inhibited ASK1 activity in vitro. Furthermore, coimmunoprecipitation analysis revealed a physical interaction between endogenous Hsp72 and ASK1 in NIH 3T3 cells exposed to mild heat shock. Hsp72 blocked both the homo-oligomerization of ASK1 and ASK1-dependent apoptosis. Hsp72 antisense oligonucleotides prevented the inhibitory effects of mild heat shock on H(2)O(2)-induced ASK1 activation and apoptosis. These observations suggest that Hsp72 functions as an endogenous inhibitor of ASK1.


Subject(s)
Heat-Shock Proteins/metabolism , MAP Kinase Kinase Kinases/metabolism , MAP Kinase Signaling System/physiology , 3T3 Cells , Animals , Apoptosis/physiology , Enzyme Activation , Genes, Reporter , HSP72 Heat-Shock Proteins , Heat-Shock Proteins/genetics , Hot Temperature , Humans , Hydrogen Peroxide/pharmacology , MAP Kinase Kinase Kinase 5 , MAP Kinase Kinase Kinases/genetics , Mice , Oligonucleotides, Antisense/metabolism , Oxidants/pharmacology , Protein Binding , Recombinant Fusion Proteins/metabolism
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