1.Histomorphologic Changes of Small Intestinal Mucosa after Irradiation in Rats.
Chan Hwan KIM ; Eun Sook CHANG ; Keon Young KWON ; Kwan Kyu PARK ; Ok Bae KIM
Korean Journal of Pathology 1999;33(9):639-651
Inadvertent application of ionizing radiation, a valuable tool in diagnostic radiology and radiotherapy, results in injury and death of adjacent normal cells, inducing gene mutations or even producing latent cancers. Captopril, an angiotensin I converting enzyme (ACE) inhibitor, has been reported to prevent the structural and functional changes in variable organs, such as lung and kidney, from radiation injury in different experimental animal models. An experiment was carried out to elucidate the radiation-induced histomorphologic changes of small intestine, especially jejunum, and to determine whether captopril can reduce or prevent the radiation-induced injuries in jejunum. Twenty-six healthy Sprague-Dawley rats were used. Experimental group (n=24) was divided into two large groups: the first one (n=16) was treated with two different single dose (9 Gy, 17 Gy) irradiation only and was sacrificed at 12 hours and at 8 weeks following irradiation; the second one (n=8) received captopril 500 mg/l per oral continuously after same doses of irradiation and was sacrificed at 8 weeks. The control group (n=2) was maintained on a stock diet in a same period of experimental group and sacrificed coincidentally. On light and electron microscopy, the 9 Gy and 17 Gy 12 hours groups revealed frequent apoptosis and necrosis but extremely decreased mitotic figures of the crypt cells. However, the 9 Gy and 17 Gy 8 weeks groups and the combined irradiation with captopril groups showed extremely reduced apoptosis and necrosis with increased mitotic figures. There was good correlation between experimental groups in apoptotic count and mitotic count (p<0.05). In the 9 Gy and 17 Gy 12 hours groups, the mucosal surface was focally or diffusely fragmented and the villi were slightly to moderately distorted. Collagen deposition was very mild and confined to the lower portion of the lamina propria. The 9 Gy and 17 Gy 8 weeks groups showed more severe mucosal surface fragmentation even with foci of erosion, short and distorted villi, and more intense collagen deposition. In contrast, the combined irradiation with captopril groups revealed complete regeneration of the mucosal surface epithelium and absent collagen deposition. These findings suggest that the acute radiation injuries to small intestine occur principally in the mucosal crypt cells. Captopril, the ACE inhibitor, might provide a useful intervention in the radiation injuries of intestinal mucosa.
Animals
;
Apoptosis
;
Captopril
;
Collagen
;
Diet
;
Epithelium
;
Intestinal Mucosa*
;
Intestine, Small
;
Jejunum
;
Kidney
;
Lung
;
Microscopy, Electron
;
Models, Animal
;
Mucous Membrane
;
Necrosis
;
Peptidyl-Dipeptidase A
;
Radiation Injuries
;
Radiation, Ionizing
;
Radiotherapy
;
Rats*
;
Rats, Sprague-Dawley
;
Regeneration
2.Immunohistochemical Stain and Electron Microscopic Study on the Pericytes of Fibrovascular Diabetic Preretinal Membrane.
Kyung Ho WOO ; Kwang Soo KIM ; Keon Young KWON
Journal of the Korean Ophthalmological Society 1996;37(10):1648-1655
Seven fibrovascular diabetic preretinal membranes were examined with lightmicroscophic immunohistochemical stain and electron-microscopy to evaluate the possibility of pericytes to be involved in membrane contraction. Pericytes were positively stained with anti-actin antibody together with some stromal cells thought to be myofibroblasts presumedly. On transmission electron microscopic study, pericytes were highly active with numerous cytoplasmic processes and contained abundant microfilaments considered as actin in their cytoplasm. Pericyte/endothelial cell ratio of vascular channels were increased in some actively proliferative portion of the membranes. Myofibroblasts that contain abundant cytoplasmic microfilaments were also demonstrated in the extravascular stroma of the membranes and were very similar to the pericytes morphologically. Although the evidence that the pericytes are related to the origin of the myofibroblasts could not be demonstrated, this study suggested that the pericytes may play important roles in development and contraction mechanism of fibrovascular diabetic preretinal membranes.
Actin Cytoskeleton
;
Actins
;
Cytoplasm
;
Membranes*
;
Myofibroblasts
;
Pericytes*
;
Stromal Cells
3.Tissue engineering of urinary organs.
Ki Dong PARK ; Il Keon KWON ; Young Ha KIM
Yonsei Medical Journal 2000;41(6):780-788
Tissue engineering can serve as an alternative treatment for a malfunctioning or lost organ. Isolated and expanded cells adhere to a temporary scaffold, proliferate, and secrete their own extracellular matrices (ECM) replacing the biodegrading scaffold. The genitourinary system, composed of the kidney, ureter, bladder, urethra, and genital organs, is exposed to a variety of possible injury sites from the time of fetal development. All the urinary organs are mainly composed of smooth muscle and uroepithelial cells and which may be approached by tissue engineering techniques. A large number of materials, including naturally-derived and synthetic polymers have been utilized to fabricate prostheses for the genitourinary system. Usually, whenever there is a lack of native urologic tissue, reconstruction is considered with native non-urologic tissue, such as, gastrointestinal segments, or skin or mucosa from multiple body sites. Engineering tissues using selective cell transplantation may provide a means to create functional new genitourinary tissues. This review concerns urinary tissues reconstructed with bladder uroepithelial cells and smooth muscle cells (SMCs) implanted on biodegradable polymer matrices.
Animal
;
Biomedical Engineering*/methods
;
Bioreactors
;
Cytological Techniques/trends
;
Human
;
Stem Cells/physiology
;
Urinary Tract*
4.Surgical Management of Thoracolumbar Spine Fracture with Pedicle Screws and Inferior Laminar Hooks.
Jin Man WANG ; Kwon Jae ROH ; Yeo Hun YUN ; Young Do KO ; Jong Keon OH ; Hoon JEONG ; Dong Jun KIM
Journal of Korean Society of Spine Surgery 1998;5(1):62-69
STUDY DESIGN: Clinical and radiographic results of spine fracutre treated with pedicle screws and hooks were reviewed. OBJECTIVES: Evaluate the efficacy of tile pedicle screw and hook for thoracolumar bursting fracture. SUMMARY OF LITERATURE REVIEW: Despite of the mechanical advantage of the pedicle screw, the metal failure in short segment fusion has been reported. A biomechanical study showed additional laminar hook increased rotational strength. MATERIALS AND METHODS: Between 1994 and 1996, seventeen patients who had a Denis type B bursting fracture of the thoracolumbar spine were treated by posterior instrumentation with pedicle screws and laminar hooks and auterior interbody fusion after partial corpectomy. They have been followed for an average of 13.4 months. RESULTS: At last follow-up, radiographs showed successful fusion of the injured spinal segment in all patient. The subsidence of grafts which were used In anterior interbody fusion was an average of 0.76mm. There was a loss of 2.6 degrees on average in the correction of the kyphosis. No patients had screw breakage or loosening. CONCLUSIONS: We concluded that posterior fixation with screws and hooks, anterior decompression by partial corpectomy, and strut-grafting in patient who had a Denis type B bursting frafture of the thoracolumbar spine yielded good radiographic and functional results.
Decompression
;
Follow-Up Studies
;
Humans
;
Kyphosis
;
Spine*
;
Transplants
5.Subcutaneous Emphysema and Inadvertent One Lung Ventilation during General Anesthesia for Laparascopic Hysterectomy.
Keon Sik KIM ; Chae Kyu KANG ; Hwa Ja KANG ; Young Kyoo CHOI ; Ok Young SHIN ; Moo Il KWON
Korean Journal of Anesthesiology 1995;29(6):922-926
In obsterics and gynecology laparoscopic surgery is increasing in numbers and gaining wide popularity replacing classical laparotomy and is becoming new trend in surgical fields. Laparoscopic surgery is favoured over the classical laparotomy because of numerous advantages but it can cause complications by insuffulatory CO2 to induce artificial pneumoperitoneum. Therefore, wide knowledges and thorough understandings of anesthesiologist on the prevention of complications and their treatments are essential. Authors present one case that the patient developed subcutaneous emphysema and ateleciasis on right upper lobe, pulmonary edema in left side lung resulting from inadvertent one lung ventilation during laparoscopic hysterectomy under general anesthesia and on trendelenberg position.
Anesthesia, General*
;
Gynecology
;
Humans
;
Hysterectomy*
;
Laparoscopy
;
Laparotomy
;
Lung
;
One-Lung Ventilation*
;
Pneumoperitoneum, Artificial
;
Pulmonary Edema
;
Subcutaneous Emphysema*
6.Botulinum toxin type A therapy in cluster headache: A case report.
So Young KWON ; Dong Eon MOON ; Young Hoon KIM ; Sung Hyun LEE ; Keon Hee RYU
Anesthesia and Pain Medicine 2012;7(1):12-15
Cluster headache is a severe pain syndrome with a piercing, tearing sensation, nicknamed the suicide headache. It is associated with an autonomic symptom. No effective therapy is available in approximately 4-15% of patients with cluster headache. One of the treatment methods is occipital nerve block. It is conventionally performed with local anaesthetics, and in this case we used the botulinum toxin type A. Botulinum toxin is an effective therapeutic agent for various disorders, and has recently been discovered to be an effective treatment for chronic migraine. The efficacy of Botulinum toxin in headache invokes possible neurogenic effects that may reduce or even prevent sensitization of both the peripheral and central nervous system. Therefore, we describe a case of a 45-year-old male with a cluster headache that could not be controlled with conventional therapy. We performed botulium toxin type A therapy. Cluster headache VAS showed improvement after occipital nerve block using the botulinum toxin A.
Botulinum Toxins
;
Botulinum Toxins, Type A
;
Central Nervous System
;
Cluster Headache
;
Headache
;
Humans
;
Male
;
Middle Aged
;
Migraine Disorders
;
Nerve Block
;
Sensation
;
Suicide
7.Comparision of Propofol and Thiopental Sodium as Anesthetic Induction Agents for Electroconvulsive Therapy.
Chae Kyu KANG ; Ok Young SHIN ; Keon Sik KIM ; Young Kyoo CHOI ; Moo Il KWON
Korean Journal of Anesthesiology 1996;31(2):184-189
BACKGROUND: Electroconvulsive(ECT) or electroshock therapy(EST) remains controversial and its indications are still the subject of discussion. Despite both medical and legal opposition, it is still widely practiced. The aim of ECT is to produce a grand mal seizure rather than the electrical stimulus which is responsible for the therapeutic effect. This causes widespread physiological changes, particularly affecting the cardiovascular and nervous system. The anesthetic agents for ECT should provide a smoooth rapid induction, a rapid recovery and attenuation of the physiologic effect of ECT. METHODS: Propofol(1 mg/kg) and thiopental sodium(2 mg/kg) were compared as anesthetic agents for ECT in 20 patients on four occasions in a repeated measure crossover study. In each patients receiving propofol or thiopental sodium on different occasions, arterial pressure, heart rate, seizure duration and recovery time were recorded. RESULTS: The incidence of discomfort on injection was significantly higher with propofol (47.5%) compared to thiopental sodium (2.5%). The duration of seizure with propofol was 37+/-11.3 sec and thiopental sodium was 41.2+/-11.6 sec but it was not significant(P=0.11). The increase in systolic and diastolic arterial pressure and heart rate were higher with thiopental sodium. Recovery time was significantly shorter with thiopental sodium (476.5+/-47.7 sec) compares to propofol (506.6+/-62.2 sec) (P<0.05). CONCLUSIONS: Propofol is more effective than thiopental sodium at obtunding the hypertensive to ECT without causing significant hypotention.
Anesthetics
;
Arterial Pressure
;
Cross-Over Studies
;
Electroconvulsive Therapy*
;
Electroshock
;
Heart Rate
;
Humans
;
Incidence
;
Nervous System
;
Propofol*
;
Seizures
;
Thiopental*
8.Effects of Blood-Brain Barrier Disruption on Cerebral Oxygen Balance.
Doo Ik LEE ; Young Kyu CHOI ; Dong Ok KIM ; Keon Sik KIM ; Ok Young SHIN ; Moo Il KWON
The Korean Journal of Critical Care Medicine 1999;14(2):126-130
BACKGOUND: Disruption of the blood-brain barrier (BBB) can alter the internal milieu and may increase the release of excitatory amino acid neurotransmitters or catecholamines, which may affect metabolic rate or coupling. This study was performed to evaluate whether disruption of BBB by unilateral intracarotid injection of hyperosmolar mannitol would alter oxygen supply/consumption balance in the ipsilateral cortex. METHODS: Rats were anesthetized with 1.4% isoflurane using mechanical ventilation via tracheostomy. 25% mannitol was administered at a rate of 0.25 mlxkg-1s-1 for 30 s through unilateral internal carotid artery. The BBB transfer coefficient (Ki) of 14C-alpha-aminoisobutyric acid was measured in one group (N=7) after administering mannitol. Regional cerebral blood flow (rCBF), regional arterial and venous O2 saturation and O2 consumption were measured in another group using a 14C-iodoantipyrine and microspectrophotometry (N=7). RESULTS: Vital signs were similar before and after administering mannitol. Ki was significantly higher in the ipsilateral cortex (IC) than in the contralateral cortex (CC), (22.3+/-8.4 vs 4.4+/-1.1 microliterxg-1min-1). rCBF was similar between IC (105+/-21 mlxg-1min-1) and the CC (93+/-20). Venous O2 saturation was lower in the IC (43+/-7%) than in the CC (55+/-4). O2 consumption was higher in the IC (9.6+/-3.0 mlx100 g-1min-1) than in the CC (6.7+/-1.5). CONCLUSIONS: Our data suggested that increasing permeability of the BBB increased cerebral O2 consumption and deteriorated cerebral oxygen balance.
Animals
;
Blood-Brain Barrier*
;
Brain
;
Carotid Artery, Internal
;
Catecholamines
;
Excitatory Amino Acids
;
Isoflurane
;
Mannitol
;
Microspectrophotometry
;
Neurotransmitter Agents
;
Oxygen*
;
Permeability
;
Rats
;
Respiration, Artificial
;
Tracheostomy
;
Vital Signs
9.MR Imaging of Uterine Cervical Carcinoma: Is Contrast-enhanced Imaging Useful in Staging?.
Keon Woo KIM ; Tae Hun KIM ; Sang Kwon LEE ; Young Joo KIM ; Duk Sik KANG
Journal of the Korean Radiological Society 1998;39(6):1195-1201
PURPOSE: To evaluate the usefulness of contrast-enhanced T1-weighted MR imaging in the diagnosis and stagingof uterine cervical carcinoma. MATERIALS AND METHODS: MR images (T1WI, T2WI and CE-T1WI) of 40 patients withhistologically proven uterine cervical carcinoma were reviewed by three radiologists. Tumor visualization, signalintensity, degree of enhancement, delineation of tumor margin, assessment of parametrial involvement, andevaluation of pelvic lymph node metastasis were analynized on each sequence, retrospectively. We compared theaccuracy of CE-T1WI with that of T2WI in the diagnosis and staging of uterine cervical carcinoma. RESULTS: Tumorswere detected in 35/40 cases (87.5%) on T2WI, and in 34/40 (85.0%) on CE-T1WI. On T2WI, signal intensities of allvisualized tumors were more hyperintense than those of normal cervical stroma. The signal intensities of enhancedtumors were lower(79.4%), similar to (5.9%), or higher than (14.7%) those of well-enhanced normal myometrium. Inthe assessment of parametrial involvement and the evaluation of pelvic lymph node metastasis, accuracy during eachsequence was 85.7% (12/14) and 100% (28/28), respectively. With regard to delineation of tumor margin, nostatistical difference was found between CE-T1WI and T2WI, though in cases of lesions greater than 3 cm in maximalsize, the margin was clearer in 14 cases, and less clear in 4 cases, on CE-T1WI than on T2WI, with a significantstatistical difference. The accuracy of tumor staging was 78.6% (11/14) on T2WI, and 71.4% (10/14) on CE-T1WI. CONCLUSION: There was no significant statistical difference in tumor visualization, accuracy of staging, andevaluation of pelvic lymph node metastasis between T2W1 and CE-T1WI. CE-T1WI was superior to T2WI in delineatingthe margin of tumors more than 3 cm in maximal size. Contrast-enhanced T1WI appears to be useful for evaluatingthe extent of large cervical carcinomas.
Animals
;
Diagnosis
;
Female
;
Humans
;
Lymph Nodes
;
Magnetic Resonance Imaging*
;
Mice
;
Myometrium
;
Neoplasm Metastasis
;
Neoplasm Staging
;
Retrospective Studies
10.The Effects of Lidocaine and Clonidine Premedication on Cardiovascular Response during Induction of Anesthesia with Ketamine.
Hyun Wha LEE ; Keon Sik KIM ; Hwa Ja KANG ; Young Kyoo CHOI ; Moo Il KWON ; Kwang Il SHIN
Korean Journal of Anesthesiology 1995;28(5):618-625
Ketamine may increase blood pressure and heart rate and should be avoided in hypertensive patients. However, in hypovolemic and asthmatic patients, ketamine is used as an induction agent because of its cardiovascular stimulating effect and bronchodilating effect. This study aims to assess the effects of clonidine and lidocaine on the cardiovascular response of intravenous ketamine administration during induction of anesthesia. sixty patients were divided into 3 groups as followed: group I: control ( received no lidocaine or no clonidine) group II: received lidocaine (1.5 mg/kg IV) 3 minutes before intubation group IIl: received clonidine (0.3 mg PO) 90 minutes before induction of anesthesia The changes of blood pressure, heart rate and rate pressure product following intubation were measured at different time interval (before induction,before intubation just after intubation, postintubation 1, 3, 5, 10 min) and compared with the value of control (2 hours before induction of anesthesia). The results are as follows 1) Group I and Group II: The systolic and diastolic blood pressure increased significantly compared to the control value from preinduction to 5 minutes after intubation(p<0.05). It recovered to the control value in 10 minutes, but heart rate and rate-pressure product increased significantly for 10 minutes after intubation(p<0.05) 2) Group III: The systolic and diastolic blood pressure, heart rate and rate-pressure product of preinduction and preintubation values decreased significantly compared to control values but 1 minute after intubation,all values increased significantly(p<0.05). The systolic and diastolic blood pressure and rate-pressure product values recovered to control value in 3 minutes after intubation and heart rate recovered in 5 minutes. Comparing group III with group I and II, it showed significant changes(p<0.05). From the above results, it can be concluded that clonidine inhibits cardiovascular stimulating response by ketamine during induction of anesthesia. the above results, it can be concluded that clonidine inhibits cardiovascular stimulating response by ketamine during induction of anesthesia.
Anesthesia*
;
Blood Pressure
;
Clonidine*
;
Heart Rate
;
Humans
;
Hypovolemia
;
Intubation
;
Ketamine*
;
Lidocaine*
;
Premedication*