Preparation of Bone Slide for Histomorphometry in Forensic Anthropology / 대한법의학회지

Microscopic analysis of bone is very useful method for estimating age at death of individual identification, diagnosing metabolic disorder or dietary deficiency in bone tissue, and differentiating human bone or not when applied to fragmentary skeletal remains. The purpose of this study was to establish a systematic method for preparing bone tissues by manual grinding method and offer help in application of related histomorphometric field such as estimating age at death. For this, human bone tissues of rib and femur from cadavers were prepared and considered histomorphological variations of osteon with light microscope. As results of this study, Type II osteons, smaller versions of Intact osteons (Type I) that form by radial remodeling of a preexisting Haversian canal, were distinguished from double-zonal osteons, one of the osteons that exhibit hypercalcified ring within their concentric lamellae, by the lack of an internal reversal line and the parallel contours of lamellae, and it is possible to suggest metric basis for drifting osteons as counting one osteon with the exception of size measurement. By applying this method of present study, one could easily make a bone tissue all oneself that would be helpful for establishing basic data in physical and forensic anthropology.

Alteration of Ionic Zinc Distribution in Rat Spinal Ganglion by Inflammatory Pain Stimulus: Autometallography / 대한해부학회지

This study was designed to investigate any correlation between the mechanism of pain development and changes of histochemically reactive zinc contents in the rat spinal ganglion following complete Freund's Adjuvant (CFA) injection, as an inflammatory pain model. Male Sprague-Dawley rats (270~290 g) were used for this study. Surgeries were done under anesthesia using pentobarbital (30 mg/kg). we injected 200 microliter of CFA subcutaneously in the dorsal aspect of one hind paw using a 30- gauge needle and an 1 mL syringe. Semmes-Weinstein monofilaments was used to test for mechanical hyperalgesia. Finally, zinc selenite autometallography (AMG) was done by Danscher's method. The rat suffered from severe painful swelling of the hindpaw 1 day after a CFA inoculation. Changes in pain threshold were significantly changed on 1 day, and lasted during experiment period of 3 weeks after the CFA inoculation. In control group, ganglion cells vary in size from 15 to 100 micrometer. The smaller neurons are strongly stained with AMG, whereas the larger cells are not almostly stained. Each large ganglion cell is surrounded by perineuronal satellite cells, showing apparent AMG stainity. In experiment group, AMG-positive small ganglion cells increased on 1 day after CFA inoculation, and showed a peak in cell number at 3days group, and decreased gradually after 7 days. We found a small number of large-sized ganglion cells with AMG stainity 7 days and 3 weeks after CFA inoculation. Our results indicate that zinc may be involved in pain mechanism in the spinal ganglion level.

Decrease in Zinc Concentration in the Rat Spinal Gray Matter Induced by Peripheral Nerve Ligation, and its Relations with Increased Pain Threshold / 대한해부학회지

This study was designed to investigate any correlation between the mechanism of pain development and changes of histochemically-reactive zinc contents in the rat spinal cords following peripheal nerve ligation. Male Sprague-Dawley rats (270 ~290 g) were used for this study. We ligated a left-sided lumbar spinal nerve with silk under anesthesia using pentobarbital (50 mg/kg). Semmes-Weinstein monofilaments (Stoelting Company, Wood Dale, IL) was used to test for mechanical hyperalgesia. 30 micrometer-thick spinal cord cryosections were stained by automet-allography (Danscher, 1981). The density of zinc was significantly decreased in zinc concentration in the dorsal horn of 4th, 5th and 6th lumbar segments at 5 and 10 days after the spinal nerve ligation. Here, zinc depletion was apparent in superficial gray matter, especially layer III-IV. In addition the nerve ligated rats showed lower pain threshold. This increased pain sensation might be related with lowered vesicular zinc level in the superficial gray matter in the spinal cord. The present findings offer a proposed link between zinc and pain. Our interpretation is that there may be an extension of fine primary afferent fibers into lamina III and possibly lamina IV following peripheral nerve ligation. If further work bears out this conclusion, this would provide a possible explanation for the chronic pain states that sometimes follow peripheral nerve damage.

Case Report on the Application of Tele -education Developed for the Anatomy Education / 체질인류학회지

The authors have made an anatomy CD titled Human Anatomy (Ministry of Culture & Tourism registration number 980052) for the self study by students and have used it in anatomy classes. For better student -centered and individual education, the introduction of remote education or interactive tutorial site was inevitable. In this study, amelioration report will be presented on the development and trials of this interactive tutorial site. Total hits for attending classes were 337.5 times, making 4.1 hits per student. About 76 messages were posted on the Q&A board, less than one per student. One assignment was given per lecture and all 82 students have submitted their report. Without delay after test, all students were able to check their grades and ranks between other students. Professors were able to evaluate the percentage of correct answers per question and the average of the score. An online discussion was held for 30 minutes after each lecture. On average, 37 students were participated in the discussion. After the term, evaluation survey in the remote education or interactive tutorial on the internet was made. Eighteen students (26%) have chosen 'good', 'bad' 13 students (19%), 'not much different' 38 students (55%). One the other side, 8 (12%)-'good', 19 (28%)-'not much different', 32 (46%)-'bad' figures were shown for remote examination. From this result, it is guessed that students who are not used to using computers have shown negative feeling from the burden that they had to use a computer to take exams, not demonstrating their full ability. To see all the results of this study, you can log in at http://anatomy. hallym.ac.kr as guest ID '000' and password '000'.

Regional Distribution of Zinc Transporter 3 (ZnT-3)-Immunoreactivities in the Mouse Cerebellum / 대한해부학회지

The presence of the zinc ion pump antibody ZnT-3 in zinc enriched (ZEN) cerebellar axonal terminals was detected in immunohistochemical sections of mouse cerebellum. All the ZnT-3-immunoreactive structures appeared punctate in the cerebellar cortex, while the white matter including intrinsic nuclei were void. The staining intensity varied in the different phylogenetic divisions of cerebellum. Archicortex was stained most intensively while paleo and in particular neocortex was stained only faintly. The ZnT-3 fraction was detected mainly in the upper half of the granule cell layer (GCL), although where they appeared ultrastructurally in small folded varicosities located corresponding to axon terminals of the Golgi cells. In the molecular layer (ML), the ZnT-3 staining was found to be distributed diffusely but in perpendicular radiating pattern through the layer but with the most intense staining in the upper half of the layer. Ultrastructurally the coarse patches of staining found in the granule cell layers were corresponded to presynaptic axon terminals contacting with granule cells. No ZnT-3 staining was observed in the Purkinje cell layer. The present results suggest that the Golgi cells in the mouse cerebellum are one of the ZEN neurons in the mammalian brain. In conclusion, we first showed putative ZEN terminals in the mouse cerebellum. These results will provide a valuable aid for investigation of further localization of the ZEN neurons in the mammalian cerebellum. More work is needed to further characterize the ZEN terminals, and so autometallographical studies are currently being investigated in this laboratory.

Protection Effects of the Adrenalectomy on the Neuronal Death following Kainc Acid in the Rat Hippocampus / 대한해부학회지

Chelatable zinc ions from synaptic vesicles have been shown to contribute to neuronal death caused by stroke, epilepsy and head trauma. Elevated glucocorticoid concentration exacerbates such neuron loss, while low levels protect. We have tested the notion that the neuroprotective effect of prior glucocorticoid reduction is mediated by a reduction of zinc ions, i.e. a decrease in the level of zinc ions contained in zinc-enriched (ZEN) synaptic vesicles. The level of vesicular zinc ions was evaluated by zinc selenium AMG (ZnSeAMG) staining at 10 and 30 days after adrenalectomy (ADX). The staining intensity was significantly decreased in the hippocampus following the ADX. Adrenalectomized rats showed proconvulsive seizure behavior, i.e. shortened latency to seizure onset time and increased seizure score 3 hrs after i.p injection of kainic acid (KA). However, adrenalectomized rats showed decreased hippocampal CA3 neuronal death 24 hrs following the KA injection. The convulsive seizure in the ADX rats results from the decreased contents of the vesicular zinc in the presynaptic neurons of the hippocampus. The decreased zinc translocation following the KA injection contributes to the increased neuronal survival rates of postsynaptic neurons against the zinc toxicity in the ADX rats. The present data suggest that the glucocorticoid influences vesicular zinc concentration in the CNS.

Cytotoxic Effect of 6-OHDA on the Dopaminergic Neurons and Astrocytes in the Dorsal Raphe Nucleus of the Rat / 대한해부학회지

This study was designed to clarify the cytotoxic effects of 6-hydroxydopamine (6-OHDA) on the dopaminergic neurons and astrocytes in the dorsal raphe nucleus (DRN), and to investigate neurodegenerative changes by immuno-histochemistry. Adult male rats (Sprague-Dawley strain) weighing from 250 to 350 g were used as experimental animals. 6-OHDA (100 micrometer dissolved in 0.1% ascorbic acid) was injected into the lateral ventricle of the rat brain with the Hamilton syringe. The control rats were treated with the similar volume of 0.1 % ascorbic acid. The rats were sacrificed at the 3rd, 5th, 10th and 20th day, respectively, after the injection of 6-OHDA. The cytotoxicity of 6-OHDA resulted in severe neurodegeneration of the dopaminergic neurons in the DRN. In the 3rd day, the dopaminergic fibers were dilated. In the 5th and 10th days, the dopaminergic fibers were depleted, and dopaminergic cell bodies were shrunken. In the 20th day, the dopaminergic cell bodies were almost completely disappeared. Astroglial reactions induced by 6-OHDA were also observed in the DRN. In the 5th day, astrocytes were significantly increased as compared with that of the control value. The value were reached at its maximum by the 20th day. Based on the present results, it suggests that 6-OHDA may act as a specific neurotoxin to dopaminergic neurons in the DRN, and induce severe neurodegenerative changes. Also, it suggests that the astroglial reaction in the DRN is gradually activated during the neurodegerative changes.

Cytotoxic Effect of 5, 7-DHT on the Endogenous Glial Cells in the Dorsal Raphe Nucleus of the Rat / 대한해부학회지

This study was designed to clarify the cytotoxic effects of 5, 7-dihydroxytryptamine (5, 7-DHT) on the serotonergic neurons in the dorsal raphe nucleus, and to investigate the glial reaction during the neurodegenerative changes by light and electron microscopy. Adult male rats (Sprague-Dawley strain) weighing from 250 g to 350 g each were used as experimental animal. 5, 7-DHT (200 mg dissolved in 0.9% NaCl) was injected into the lateral ventricle of the rat brain with the Hamiton syringe fixed on stereotaxic apparatus. The control rats were given with the similar volume of 0.9% NaCl. The rats were sacrified on the 1st, 3rd, 5th, 10th and 20th day after the injection of 5, 7-DHT. The results were as follows : Glial reactions induced by 5, 7-DHT were also observed in DRN. In early experimental stage, microglial reactions prevailed, whereas astroglial reactions were prevailing in later stage. In addition, microglial cells phagocytosed and removed the degenerated cells. However, astrocytes in DRN did not show phagocytotic activities such as microglial cells. Based on the results, author thought that 5, 7-DHT act as a specific neurotoxin to serotonergic neurons in DRN, and induces severe neurodegenerative changes. The glial reactions in DRN are activated during the neurodegerative changes, and show characteristic patterns of glial reactions.

Cytotoxic Effect of 5, 7-DHT on the Serotonergic Neurons in the Dorsal Raphe Nucleus of the Rat / 대한해부학회지

This study was designed to clarify the cytotoxic effects of 5, 7-dihydroxytryptamine (5, 7-DHT) on the serotonergic neurons in the dorsal raphe nucleus, and to investigate the glial reaction during the neurodegenerative changes by light and electron microscopy. Adult male rats (Sprague-Dawley strain) weighing from 250 g to 350 g each were used as experimental animal. 5, 7-DHT (200 microgram dissolved in 0.9% NaCl) was injected into the lateral ventricle of the rat brain with the Hamiton syringe fixed on stereotaxic apparatus. The control rats were given with the similar volume of 0.9% NaCl. The rats were sacrified on the 1st, 3rd, 5th, 10th and 20th day after the injection of 5, 7-DHT. The results were as follows : The cytotoxicity of 5, 7-DHT resulted in severe neurodegenerations of the serotonergic neurons. Most degenerated cells mainly showed necrotic findings, but a few of them exhibited apoptotic features. That is, in early stage of this experiment, the degenerated cells showed edematic changes of cytoplasm, but their nuclei were relatively seen intact. In late stage, the cells showed dark degenerative changes both in their cytoplasm and nuclei. Thereafter the cells were autolysed or phagocytosed by neighboring glial cells. Based on the results, author thought that 5, 7-DHT act as a specific neurotoxin to serotonergic neurons in DRN, and induces severe neurodegenerative changes. The glial reactions in DRN are activated during the neurodegerative changes, and show characteristic patterns of glial reactions.

Effects of Dehydration on Vasopressin and Oxytocin Immunoreactive Neurons of the Hypothalamus in the Mongolian Gerbil / 대한해부학회지

The effects of dehydration on vasopressin and oxytocin immunoreactive neurons in the hypothalamus was investigated by using a immunohistochemistry. Adult Mongolian gerbil[Meriones unguiculates] were deprived of drinking water. Dehydrated animals were sacrificed on the 7th, 14th and 21st day of water retriction. The results are as follows : 1. The body weights were decreased about 1.8% daily. On the 21st day of dehydration, they were shown up to 45% compare to the control. 2. In the hypothalamus of the control group, majority of vasopressin and oxytocin immunoreactive neurons were located in the supraoptic and paraventricular nuclei. 3. Changes due to dehydrated stimulation were mainly observed in vasopressin immunoreactive neurons. And these changes in supraoptic nuclei were more severe than those in paraventricular nucleus. Size of vasopressin immunoreactived cells and of areas were increased as to proceed the dehydration. The numbers of those were increased on the 7th day of dehydration, and then they were continously decreased. 4. Although oxytocin immunoreactive neurons were slightly changed in numbers during dehydration, they were not shown conspicuous changes compare to vasopressin immunoreactive neurons. Thus it is appeared that vasopressin secretory neurons in the hypothalamus of Mongolian gerbil are affected by osmotic stress induced dehydration while oxytocin neurons may be affected by other factors.