Diabetic neuropathy is an axonal degenerative disease characterized by progressive axonal atrophy and reduced axonal transport. We were interested in the potential neuroprotective effects of nerve growth factor against diabetic neuropathies. To this aim we studied the effect of nerve growth factor on satellite cells, which might play a trophic role toward the related neuron, of the dorsal root ganglion in the streptozotocin-induced diabetic rats by electron in microscope . Diabetes was induced in rats by the streptozotocin. And recombinant human NGF was administrated everyday for 10 consecutive weeks. The results obtained are as follows : 1.In the diabetic induced group, the satellite cells revealed irregular nuclei.The neuron-satellite cell interface was more irregular and plicated than that of control. Large vacuoles and dense bodies were observed and no defects were in the ribosomes and rough endoplasmic reticulum. In the vacuoles, medium electron dense, fiber -like materials were occasionally observed. 2. In the experimental group of diabetic rats treated with NGF for 10 weeks, nucleus was round and the neuron-satellite interface was more regular. Vacuoles and dense bodies were less seen than diabetic rats. In the cytoplasm, many microtubules were observed. In these studies, we considered that streptozotocin induces changes of the satellite cell structure and NGF might improve cellular changes of the satellite cell exposed with streptozotocin.
Animals ; Atrophy ; Axonal Transport ; Axons ; Cytoplasm ; Diabetic Neuropathies ; Endoplasmic Reticulum, Rough ; Ganglia* ; Ganglia, Spinal ; Humans ; Microtubules ; Nerve Growth Factor* ; Neurons ; Neuroprotective Agents ; Rats* ; Ribosomes ; Streptozocin ; Vacuoles

Recently, in most medical schools of Korea, the educational method of gross anatomy, the first subject in medical education, has changed in several directions such as integrated lecture or problem-based learning (PBL). Therefore, the time of the lecture was constrained to reduce. The name of the gross anatomy integrated with embryology changed to 'human body and development' in Konkuk university since 2006. In addition to the classical dissection practice, the 'dissection seminar' was introduced since 2006. It was a method of dissection practice that one group demonstrate the procedure of dissection and explains the structures of the predissected cadaver to other students about the assigned subject. The questionnaire about dissection seminar was performed after the anatomy course. The most common opinion about dissection seminar was 'interesting and helpful for studying anatomy'. The common answers about the attitude were 'very positive' and 'positive'. The affirmatives during dissection seminar were in depth study and improve in collaboration. The inconveniences or lacks were insufficient time to prepare, unfairness in difficulty between the subjects, and discord among group members. The propositions for development were requirement of sufficient preparation time, request of guideline, and consideration of other schedule. As a result of self-estimation about dissection seminar, the direction of the dissection seminar have been advancing with time, and students became more interested in studying anatomy. The most important thing for maintaining the dissection seminar is making proper plan such as avoidance of examination of another subject.
Appointments and Schedules ; Cadaver ; Cooperative Behavior ; Education, Medical ; Humans ; Korea ; Problem-Based Learning ; Surveys and Questionnaires ; Schools, Medical

Osteoporosis is a major health-care problem for aging communities. And postmenopausal osteoporosis is a common disorder characterized by an increase in bone resorption relative to bone formation, generally in conjunction with an increased rate of bone turnover. Twenty female rats were used as rat model of osteoporosis. They randomly were divided into two groups: a normal control group, and calcium-free diet groups treated with bilateral ovariectomy. The animals were sacrified at 12 weeks after treatment. In the rats with osteoporosis, there was significant thining and loss of trabeculae, accompanied by a disconnection of trabeculae. And acid mucopolysaccharides were decreased in osteoporotic animals. In order to setup conditions of invivo micro-CT, proper anesthetic is ketamine (50 mg/kg) /xylazine (6 mg/kg). And proper breathing rate of experimental animals is 1.3~1.6/sec. Our finding suggest that bilateral ovariectomy and calcium-free diet induce decrease in thickeness of trabecular bone and decrease in acid mucopolysaccharide, therefore cause weakness of bone. And micro-CT imaging system is useful to evaluate trabecular bone. Anesthetic time, anesthetics and respiration rate also signify much in micro-CT imaging system.
Aging ; Anesthetics ; Animals ; Bone Resorption ; Diet ; Female ; Glycosaminoglycans ; Humans ; Ketamine ; Models, Animal ; Osteogenesis ; Osteoporosis* ; Osteoporosis, Postmenopausal ; Ovariectomy ; Rats ; Respiration ; Respiratory Rate

To provide the information about overall test reliability and test improvement, we analyzed the first fundamental medical sciences examination at the Kon-Kuk University College of Medicine on August 23, 1997. The results are as follows: 1. The number of the items in the test is 230. The range of the scores is from 32.5 to 61.3(average percentage score: 50.0+/-6.1). Among the 39 students, three(7.7%) passed the examination with percentage scores of higher than 60. 2. The correlation coefficients between the fundamental medical sciences examination and academic records are 0.4682(the first semester in 1st grade), 0.5933(the second semester in 1st grade), and 0.6538(the first semester of 2nd grade), respectively. 3. Among the 230 items, 47(20.4%) are too difficult or too easy. Therefore these items are recommended to be discarded. 4. Among the 230 items, 115(50%) have lower discriminative indices(lower than 0.14) and 55(23.9%) have higher discriminative indices(higher than 0.23). 5. Among the 230 items, overall acceptable items are 101; the range of difficulty is 0.15~0.84 and discriminative indices are higher than 0.15. Good acceptance is shows in pharmacology and microbiology.
Humans ; Pharmacology

Previous studies showed that whole body vibration could prevent bone resorption and stimulate new bone formation. The aim of this study is to detect and track effect of whole body vibration for osteoporotic bone of OVX rats. 12 Female rats were used and allocated into 5 group, CON, SHAM, WBV 17, WBV 30 and WBV 45. Rats except SHAM group were ovariectomised to induce osteoporosis. Rats in WBV groups were stimulated whole body vibration at magnitude of 1 mm(peak-peak) and frequency 17 Hz, 30 Hz and 45 Hz, repectively, for 8 weeks (20 min, 5 days/week). The 4th lumbar in rats were scanned at a resolution of 35 micrometer at baseline, before stimulation, and 8 weeks by In-vivo Micro-CT. To detect and track changes of morphological characteristics in lumbar trabecuar bone of rats, structural parameters were measured and calculated from acquiring images. In the results, changes of structural characteristics of WBV group were smaller than those of CON group. Loss of quantity of trabecular bone in WBV 45 was the least. In contrast, that in WBV 17 was the biggest. These results showed that reasonable whole body vibration beneficially affected osteoporotic bones. In addition to, whole body vibration was likely to be substituted partly for drug treatment.
Animals ; Bone Resorption ; Female ; Humans ; Osteogenesis ; Osteoporosis ; Rats* ; Vibration*

PURPOSE: This study purposed to measure the standard volume of the cerebellum of normal Koreans who were in their 20s and 40s, and we also wished to find out the difference in the volume of the cerebellum according to gender and age. MATERIALS AND METHODS: This study collected MR brain images from 118 people in their 20s (males: 58, females: 60) and 100 people in their 40s (males: 41, females: 59), for a total of 218 people. For each of sagittal, coronal and axial sections, the cerebellar part of the images was segmented using automatic and manual methods, and the volume was then measured. In order to observe differences according to gender and age and also to observe the interactive effect between gender and age, a two-way ANOVA test was performed using gender (2 levels) and age (2 levels) as independent variables. RESULTS:The average volume of the cerebellum of Koreans in their 20s was 133.74 (cm3) and that of Koreans in their 40s was 121.83 (cm3). The average volume of the cerebellum of male Koreans in their 20s and 40s was 134.55 (cm3) and that of female Koreans was 123.06 (cm3). The volume of the cerebellum was significantly larger in Koreans in their 20s than those volumes of the cerebellum of Koreans in their 40s, and the cerebellum volumes in male Koreans were larger than those of the Korean females. Moreover, the reduction of the volume of the cerebellum with age was significantly larger in male Koreans than in the Korean females. CONCLUSION: According to the results of measuring the volume of the cerebellum for normal Koreans in their 20s and 40s, the volume was significantly different according to gender and age, and the reduction of the volume of the cerebellum with age was significantly larger in men than in women.
Brain ; Cerebellum ; Female ; Humans ; Magnetic Resonance Imaging* ; Male

BACKGROUND AND OBJECTIVES: The degree of noise induced hearing loss was determined principally according to the level and duration of noise and patient's state. The purpose of this study was to investigate the cochlear histopathology and hearing threshold immediately after noise exposure according to duration of noise exposure, and finally to draw relationship between the cochlear pathology and hearing threshold. MATERIALS AND METHOD: Each group of animals (6 ears) has been exposed for 10 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 24 hours and 48 hours to an octave band of noise with a center frequency of 4000 Hz and a sound pressure level of 110 dB. After noise exposure, the hearing thresholds of the subjects were determined with auditory brainstem response (ABR) and immediately their inner ear were fixed and observed with transmission electron microscopy (TEM). RESULTS: ABR thresholds were increased according to lengthening of duration of noise exposure. TEM findings of outer hair cells, Deiters' cells and ganglion cells showed more severe degeneration according to lengthening of duration of noise exposure. Damages of all kinds of cells appeared almost at the same time. CONCLUSION: Through the foregone study, cochlear pathology was proportioned to increased hearing threshold, and the damages of outer hair cells and ganglion cells appeared almost at the same time. It seems that not only damages of outer hair cells, but also damages of ganglion cells contribute to early hearing threshold shift during continuous intense noise exposure.
Animals ; Cochlea* ; Ear, Inner ; Evoked Potentials, Auditory, Brain Stem ; Ganglion Cysts ; Hair ; Hearing Loss ; Hearing* ; Microscopy, Electron, Transmission ; Noise ; Pathology ; Rats*

BACKGROUND AND OBJECTIVES: Quinolone-induced arthropathy is an unusual toxic effect observed in juvenile animals of multiple species. Such toxic effects are usually found in joint cartilages. The reports of chondrotoxic potential of quinolones in juvenile animals were mainly performed in weight bearing joints such as hips and knees. The purpose of this study was to investigate the morphological changes in the incudomalleolar joint of immature rats dosed with ciprofloxacin, and to draw relationship between the incudomalleolar joint pathology and hearing. MATERIALS AND METHODS: An experimental group of 21-day-old rats were administrated intraperitoneally with 200 mg ciprofloxacin/kg for 10 days. The hearing threshs of the control and experimental animals were determined with auditory brainstem response (ABR). Their ossicles were obtained and fixed, and we observed them with light microscopy (LM) and transmission electron microscopy (TEM). RESULTS: The ABR threshs were increased in the ciprofloxacin administrated group, and the increased latency of the first waves were identified in the ciprofloxacin administrated group, but there were no differences in the interval of wave I-III. The LM findings of incudomalleolar joint in the ciprofloxacin administrated group showed cartilage lesions such as disrupted articilar surface, irregular cellularity of the chondrocytes, matrix swelling, cleft formation, decreased matrix staining. The TEM findings of the incudomalleolar joint cartilage in the ciprofloxacin administrated group showed decreased bundle-like matrix and cell process, condensed nucleus, and vacuolated cytoplasm. CONCLUSION: From the results of recent works and the present study, we suggest that ciprofloxacin may induce morphological changes in the incudomalleolar joint, and that such morphological changes may induce conductive hearing loss.
Animals ; Cartilage ; Chondrocytes ; Ciprofloxacin* ; Cytoplasm ; Evoked Potentials, Auditory, Brain Stem ; Hearing Loss, Conductive ; Hearing* ; Hip ; Joints* ; Knee ; Microscopy ; Microscopy, Electron, Transmission ; Pathology ; Quinolones ; Rats* ; Weight-Bearing

The purpose of this study is to measure the standard volume of the ventricle of normal Koreans in their 20s and 40s and find out difference in the volume of the ventricle according to age and gender. We collected MR brain images from 118 people in their 20s (male 58, female 60)and 100 people in their 40s (male 41, female 59), so a total of 218 people.For each of sagittal, coronal and axial sections, the ventricular part was segmented using automatic and manual methods, and the volume was measured. In order to observe difference according to age and gender and to observe the interactive effect between age and gender, two-way ANOVA was carried out using age (2 levels)and gender (2 levels)as independent variables. The average volume of the ventricle of Koreans in their 20 s was 16.2 [cm3]and that of Koreans in their 40s was 23.1 [cm3].The average volume of the ventricle of male Koreans in their 20s and 40s was 21.9 [cm3]and that of female Koreans was 17.5 [cm3].The volume of the ventricle was significantly larger in Koreans in their 40s than those in their 20s, and in male Koreans than n female ones. Moreover, the increase of the volume of the ventricle with age was significantly larger in male Koreans than in female ones. According to the results of measuring the volume of the ventricle of normal Koreans in their 20s and 40s, the volume was significantly different according to age and gender, and the increase of the volume of the ventricle with age was significantly larger in men than in women.
Brain ; Female ; Humans ; Magnetic Resonance Imaging ; Male

BACKGROUND AND OBJECTIVES: Cisplatin is frequently used in the treatment of various forms of malignancies. It's therapeutic efficacy, however, is limited due to the occurrence of sensorineural hearing loss. Little is known about the course of hearing loss after cessation of cisplatin administration. We observed the cochlear duct morphology with normal and cisplatin treated animals. MATERIALS AND METHODS: Healthy rats (strain Sprague-Dawly, weighting 80-100 mg) were used for all experiments. Total 15 rats were selected. They were divided into two groups, a treated group and a control. Four survival groups (n=3, respectively) were assigned as the treated group. After treatment with cisplatin, each survival group was sacrificed 1, 4, 10, 20 days. Except for the normal control (n=3), twelve animals were treated with cisplatin by daily I.P. injection of 1.5 mg/kg for 8 consecutive days. RESULTS: One day after cessation of cisplatin administration, outer hair cells (OHCs) loss and stria vascularis were degenerated especially in the basal turn. At 4, 10, 20 days, the OHCs and stria vascularis morphology of the survival group were similar to those of the survival group at one day. CONCLUSION: Our findings suggest cisplatin ototoxicity is predominantly involved in the basal turn of cochlear duct. This finding was significantly correlated with high frequency hearing loss of cisplatin ototoxicity.
Animals ; Cisplatin* ; Cochlear Duct ; Hair ; Hearing Loss ; Hearing Loss, Sensorineural ; Rats ; Stria Vascularis