Perinatal asphyxia can cause ischemic injury to immature kidney of neonates. Proximal renal tubule is the most sensitive area, showing various manifestations ranging from mild reversible injury to irreversible tubular necrosis. Aminoglycosides can be nephrotoxic in therapeutic range in immature or damaged kidney. Thess are the very important factors to be taken into corsideration on fluid therapy and nephrotoxic drugs in neonates. The purpose of this study is to detect renal dysfunction resulting from asphyxia and gentamicin treatment. The results were as follows; 1) Urinary 2-microglobulin concentration was significantly higher in neonatal asphyxia group irrespective of meconium stain (p<0.05). The group with neonatal asphyxia only (Ia) showed a gradual decline in urinary 2-microglobulin concentration and no significant difference shown when compared with control group on 7 days old (p>0.05). The group with neonatal asphyxia and meconium stain (Ib) received gentamicin for 7 days. Their urinary 2-microglobulin concentration dropped on 4 the day and increased again on 7 th day (p<0.05). The group with meconium stain only(3) showed no significant difference in urinary 2-microglobulin concentration when compared with control group (p>0.05). 2) No differences were shown in serum creatinine, serum sodium level and urinary creatinine concentrations between each group (p>0.05). 3) No differences were shown in creatinine clearance between each group (p>0.05).Fractional excretion of urinary sodium (FENa) was significantly higher on lst day in group, I, but no differences were shown afterwards (p>0.05). 4) There is no relationship between urinary 2-microglobulin concentration and serum creatinine level, creatinine clearance of FENa. 5) No differences were shown in incidence of renal dysfunction between each group. In conclusion, acute tubular injury by perinatal asphyxia recovered soon after birth. But nephrotoxic gentamicin worsened the recovering tubular injury. In case of mild fetal hypoxia without neonatal asphyxia, proximal tubular injury was not significant.
Aminoglycosides ; Asphyxia* ; Creatinine ; Fetal Hypoxia ; Fluid Therapy ; Gentamicins* ; Humans ; Incidence ; Infant, Newborn* ; Kidney ; Kidney Tubules, Proximal ; Meconium ; Necrosis ; Parturition ; Sodium

The category of striatal complex contains caudate nucleus, putamen, nucleus accumbens septi, and olfactory tubercle. The striatal complex is composed of two compartments, dorsal and ventral striatum. In the striatum, cholinergic neuron is known as one of the most important intrinsic neurons, but there were little morphological reports about the early postnatal expression of mouse striatal cholinergic neurons. So, we planned to investigate the distribution of mouse striatal cholinergic neurons in their early postnatal period by the immunohistochemistry. We used ICR mouse as the experimental animals and divided them into 5 groups according to their postnatal age : 3-day, 1-week, 2-week, 4-week, and 6-week. Immunohistochemistry was done with anti-choline acetyl transferase antibody (chemicon). The results were as follow. 1 The striatal cholinergic neurons are already detected in the 3-day group, but the intensity was weak and the expression rate was extremely low. In the caudoputamen, the cholinergic expression rate was increased significantly between 3-day and 2-week. And in the nucleus accumbens septi, it was increased significantly between 1-week and 2-week. 2. The cholinergic expression rates of the adult mouse striatum were similar in both compartments. But, the difference of maturational time was noted. In the dorsal striatum, the cholinergic expression rate was increased significantly in the first postnatal week, but in the ventral striatum, it was approached to the adult level only after second postnatal week. In conclusion, the cholinergic expression rate in the mouse striatum was significantly increased after birth. And it was approached nearly to the adult level after 2-week of postnatal age. But, according to the compartments or rostrocaudal subdivisions, the difference of maturational time was noted.
Adult ; Animals ; Basal Ganglia ; Caudate Nucleus ; Cholinergic Neurons* ; Humans ; Immunohistochemistry ; Mice* ; Mice, Inbred ICR ; Neurons ; Nucleus Accumbens ; Olfactory Pathways ; Parturition ; Putamen ; Transferases

No abstract available.
Adult* ; Humans ; Respiratory Distress Syndrome, Adult*

No abstract available.
Apgar Score* ; Humans ; Hydrogen-Ion Concentration* ; Infant, Newborn*

Tyrosine hydroxylase-immunoreactive (TH-IR) neurons are known to exist in the substantia nigra pars compacta (SNpc), but not in the striatum in normal rats. In this study, injection of 6-OHDA into the 7 or 14 day neonatal rat striatum resulted in the appearance of ectopic TH-IR neurons in striatum. TH-IR cells were observed as early as postlesion day 3 and confirmed as neurons by TH/NeuN double immunohistochemistry. One or two neurons were found in most striatal sections at post-lesion day 4 where they were preferentially located in the ventro-lateral striatum, striatopallidal junction and globus pallidus. A small portion of these neurons persisted at least until post-lesion day 56, the oldest age studied. TH-IR neurons were found bilaterally in 6-OHDA-lesioned animals, but never in normal or vehicle-injected controls. To determine if these neurons resulted from stem cells, bromodeoxyuridine (BrdU) was injected daily for the first five days to label dividing cells. There was no co-localization of TH and BrdU immunoreactivity, excluding the possibility of stem cells as the source of these neurons. Although the TH-IR neurons were not numerous, their appearance following injury to the nigrostriatal system suggests that there is a capacity in neonatal brain to compensate for this lesion by upregulating dopaminergic phenotypic characters in pre-existing cells. The mechanism underlying this interesting phenotypic plasticity is unknown, but may be relevant to developing novel therapies for Parkinson's disease through stimulation of the brain's own potential for repair.
Animals ; Brain ; Bromodeoxyuridine ; Globus Pallidus ; Immunohistochemistry ; Neurons* ; Oxidopamine ; Parkinson Disease ; Plastics ; Rats* ; Stem Cells ; Substantia Nigra ; Tyrosine 3-Monooxygenase ; Tyrosine*

Normal angiogenesis is very important in the embryonic period and even in the postnatal period. If the vascularization is inadequate or excessive, several pathologic conditions may develop. Angiogenesis is well controlled and there are several angiogenic factors. Vascular endothelial growth factor (VEGF) has been identiified as an endothelial cell specific mitogen with potent angiogenic properties. Recently, a matricellular protein known as SPARC (secreted protein, acidic and rich in cysteine) is also proposed as one of new angiogenic factors. So, I planned to investigate the expression pattern of these two factors in the rat retina and to correlate their expression pattern with intraretinal vascularization. I used Sprague-Dawley rat as the experimental animals and divided them into 7 groups according to their postnatal age: 0-day, 3-day, 7-day, 14-day, 21-day, 28-day and adult. Immunohistochemistry was done. The results were as follows. 1. No SPARC immunoreactivity is observed in neural retina until postnatal day 7. At that time, weak immunore-activity is noted and it is gradually increased. The most intense immunoreactivity is noted at postnatal day 21 and 28. SPARC immunoreactivity is restricted in the nerve fiber layer and especially prominent around the blood vessels. Although SPARC immunoreactivity is much weaker than that of GFAP, the expression patterns of both factors are similar to each other. But, no SPARC immunoreactivity is observed in the adult retina. 2. Weak VEGF immunoreactivity is observed in the nerve fiber layer, ganglion cell layer and inner portion of inner nuclear layer even at postnatal day 0. After postnatal day 14, VEGF immunoreactivity is dramatically decreased in the nerve fiber layer, but it still remained in the ganglion cell layer and inner portion of inner nuclear layer. Although immunoreactivity is most intense at postnatal day 14 and 21, VEGF immunoreactivity is still observed in the ganglion cells at postnatal day 28 and adult. The spatial and temporal patterns of VEGF expression suggest that VEGF may function as a direct angiogenic factor in the retinal angiogenesis of rat. In the contrary, SPARC immunoreactivity is observed transiently in some period. So, SPARC is seemed to be a regulator that is involved only in limited steps of the retinal angiogenesis.
Adult ; Angiogenesis Inducing Agents ; Animals ; Blood Vessels ; Endothelial Cells ; Ganglion Cysts ; Humans ; Immunohistochemistry ; Nerve Fibers ; Rats* ; Rats, Sprague-Dawley ; Retina* ; Retinaldehyde ; Vascular Endothelial Growth Factor A*

OBJECTIVES: Retinopathy of prematurity (ROP) is one of the major cause of vision loss among children. Recently, the prevalence of ROP is markedly increasing as the survival rate of very-low-birth-weight premature infants has been improved. It is widely accepted that retinal hypoxia results in the release of factors influencing new blood vessel growth. But, it is little known about the morphological changes of retinal astrocytes and Muller cells in the ROP model. So, we planned to investigate the morphological changes of those retinal glial cells induced by alternating hyperoxic and hypoxic injury in ROP. METHODS: Newborn rats (postnatal day 6) were exposed to two different oxygen concentrations alternating every 24 hours until postnatal day 14. Used oxygen concentrations were 10~15% for hypoxic episode and 55~80% for hyperoxic episode. Afterthen, they were returned to room air. A group of animal served as a room air control. Retinal vascularity was assessed by ADPase reaction and morphology of retinal glial cells was observed using transmisson electron microscope. RESULTS: Preretinal neovascular tufts were observed in 2 out of 12 animals of group III (75/10%) and 4 out of 12 animals of group IV (80/10%), respectively. There was no remarkable structural change of astrocytes. But we could observe some morphological changes of Muller cells. Retraction of the radial processes of Muller cells and breaking of basal lamina were noted at the site of preretinal neovascularization. Decrease in the space occupied by the cytoplasmic processes of Muller cells was observed in the inner nuclear layer of group IV retinae. Infiltration of microglia or macrophage into the vitreo-retinal interface and the site of extravasation was noted. Findings suggestive of neuronal cell death were also observed especially in the inner nuclear layer. CONCLUSIONS: Morphological change of Muller cells and resultant loss of integrity of internal limiting membrane seemed to be the most important step for preretinal neovascularization. But, no structural changes of astrocytes were noted.
Animals ; Anoxia ; Apyrase ; Astrocytes* ; Basement Membrane ; Blood Vessels ; Cell Death ; Child ; Cytoplasm ; Ependymoglial Cells* ; Humans ; Infant, Newborn ; Infant, Premature ; Macrophages ; Membranes ; Microglia ; Models, Animal* ; Neuroglia ; Neurons ; Oxygen ; Prevalence ; Rats* ; Retina ; Retinaldehyde ; Retinopathy of Prematurity* ; Survival Rate

The cholinergic neurons in the striatal complex are the major interneurons that integrate the informations incoming to and outflowing from the striatum. The shape of synapses may change even after birth and the synaptic morphology reflects the functional state of synapse. However, it is not well known about the synaptic morphology of the mouse striatal cholinergic neurons in their early postnatal life. Thus, we investigated the synaptic morphology of the mouse striatal cholinergic neurons in their early postnatal life by the electron microscopy combined with immunohis-tochemistry. In addition, we investigated the trends of change in synaptic morphology and whether the difference between two compartments exists or not. Experimental animals which are ICR mice, were divided into 5 groups according to their postnatal age: 3-day, 1-week, 2-week, 4-week, and 6-week. Pre-embedding immunohisto-chemistry was done with anti-choline acetyl transferase antibody. The results were as follows. 1. In synapses that immunoreactive terminals constitute the presynaptic components, most of synapses are symmetric type in all age groups (p<0.05). Most of synapses in the dorsal striatum are symmetric form from 1-week of postnatal age, but it is not prominent in the ventral striatum until 2-week of postnatal age. 2. In synapses that immunoreactive terminals constitute the postsynaptic components, both symmetric and asymmetric synapses are noted in similar proportions (p<0.05). There are no difference in the synaptic morphology between dorsal and ventral striatum. 3. No specific findings are observed in synaptic curve according to the postnatal age or compartment. In conclusion, the synaptic morphology of mouse striatal cholinergic neurons is similar to mature pattern from 2-week of postnatal age. And it is thought that period between birth and 2-week of postnatal age is the critical period for synaptogenesis. The synaptic curve does not reflect the degree of synaptic maturity. Further investigations will be required to generalize the synaptic curve as a marker for synaptic maturity.
Animals ; Basal Ganglia ; Cholinergic Neurons* ; Critical Period (Psychology) ; Humans ; Immunohistochemistry ; Interneurons ; Mice* ; Mice, Inbred ICR ; Microscopy, Electron ; Parturition ; Synapses ; Transferases

In the stratified squamous epithelium, most of basal cells in the entire epithelium function as stem cells. But many researchers report that stem cells in the corneal epithelium are located exclusively in the limbus. We planned to investigate the morphological characteristics of migrating corneal epithelial cells by the electron microscopy. Sprague-Dawley rats at fullterm, postnatal day 5, 10, 15, and adult were used as experimental animals. The results are as follows. 1. Stratification of the corneal epithelium : The number of layers in the corneal epithelium was dramatically increased in the period between postnatal day 10 and 15. 2. Migration of the corneal epithelial cells : In the groups of postnatal day 10 and adult, wide intercellular spaces were noted. Especially in the adult, the limbal side of basal cells was being lifted from the Bowman's membrane and centripetal polarity of them are noted. According to the above results, the wide intercellular spaces at postnatal day 10 seems to be resulted from the migration of corneal epithelial cells for epithelial stratification. The centripetal polarity of limbal basal cells in adult rat suggests that only the limbal basal cells may function as stem cells in that period.
Adult ; Animals ; Bowman Membrane ; Epithelial Cells* ; Epithelium ; Epithelium, Corneal ; Extracellular Space ; Humans ; Microscopy, Electron ; Rats* ; Rats, Sprague-Dawley ; Stem Cells

Cancer development is accompanied by genetic events like losses, gains and amplification of certain chromosome regions or alterations of chromatin structure. Array-based CGH (Array-CGH) is a highly comprehensive, sensitive and fast technique to allow investigation of general changes in target oncogenes and tumor suppressor genes. Recently, the prevalence of colon cancer is rapidly increasing in Korea and now it is the fourth leading cause of cancer death. So, the purpose of this study is to examine genomic alterations in colon cancer cell lines and to search novel genes which might be related to the development of colon cancer. In this study, genomic alterations are analyzed by using array-CGH in three colon cell lines from Korean, SNU-81, SNU-407 and SNU-1047. We observed numerous chromosomal imbalances from all cell lines. The common chromosomal gains were observed in 1p36.33, 1q22, 1q32.1, 2q35, 8p12, 8q22.3, 14q32.33, 16p13.3, and 16q24. Common chromosomal losses were found in 4q22.1, 9q13, 14q21.1, 14q32.33, 20p12.1, Xq21.1, and Yq11.223. Gains of 1p, 2q, 8p, and 8q or losses of 4q, 14q and 20p are already known to be associated with the colon cancer development. For gene alterations, we could see gains of some genes such as ELF3 and AAMP, which were already reported to be associated with colon cancer. Also, we could find some gene alterations which were known to be associated with other cancer types. These genes were GON4L, RNPEP, TMBIM1, TIMM17A, GPBAR1, PPP1R13B and SOX8. Besides, we found alterations of new genes such as PKND and LEPROTL1. The association of these genes with colon cancer is first demonstrated here. These genes may be the novel candidate genes functioning in the development of colon cancer. In conclusion, array-CGH demonstrated the complexity of genetic aberrations in several colon cell lines. These data about the patterns of genomic alterations could be a basic step for understanding more detailed genetic events in the carcinogenesis and also provide information about possible target genes for diagnosis and treatment in colon cancer.
Cell Line ; Chromatin ; Colon ; Colonic Neoplasms ; Genes, Tumor Suppressor ; Korea ; Nucleic Acid Hybridization ; Oncogenes ; Prevalence