• International Journal of Stem Cells
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• v.15 no.2
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• pp.217-226
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• 2022

Background and Objectives: Stroke is the most common cause of human death and functional disability, resulting in more than 5 million deaths worldwide each year. Bone marrow mesenchymal stem cells (BMSCs) are a kind of stem cell that are able to self-renew and differentiate into many types of tissues. Therefore, BMSCs have the potential to replace damaged neurons and promote the reconstruction of nerve conduction pathways and connective tissue. However, it remains unknown whether transplanted BMSCs promote angiogenesis or improve the tissue microenvironment directly or indirectly through paracrine interactions. This study aimed to determine the therapeutic effect of BMSCs on ischemic stroke with hypertension in a rodent model and to explore the possible mechanisms underlying any benefits. Methods and Results: Middle cerebral artery occlusion was used to establish the experimental stroke model. The area of cerebral infarction, expression of vascular endothelial growth factor (VEGF) and glial cell line-derived neurotrophic factor (GDNF), and increment of astrocyte were measured by TTC staining, western blot, real-time quantitative polymerase chain reaction (RT-qPCR) and immunocytochemistry. The results showed a smaller area of cerebral infarction and improved neurological function scores in animals treated with BMSCs compared to controls. The results of RT-qPCR and western blot assays showed higher expression of VEGF and GDNF in BMSC-treated animals compared with controls. Our study also showed that one round of BMSCs transplantation significantly promoted the proliferation of subventricular zone and cortical cells, especially astrocytes, on the ischemic side following cerebral ischemia. Conclusions: Above findings support that BMSCs have therapeutic effects for ischemic stroke complicated with hypertension, which may occur via up-regulated expression of VEGF and GDNF and reduction of neuronal apoptosis, thereby promoting the recovery of nerve function.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.12 no.2
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• pp.126-132
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• 2001

Background and Objectives : Signal traduction through phospholipase C(PLC) participate in the regulation of cell growth and differentiation. Growth factors bind to their receptors and thereby induce tyrosine phophorylation of the phospholipase C-${\gamma}$1(PLC-${\gamma}$1). PLC-${\gamma}$1 is a substrate for several receptor tyrosine kinases and its catalytic activity is increased by tyrosine phosphorylation. Tyrosine kinase phosphorylation of PLC-${\gamma}$1 stimulates PLC activation and cell proliferation. However the signal transduction pathway and the significance of PLC in injured recurrent laryngeal nerve regeneration is unknown. Therefore after we obtained fuctionally recovered rats using PEMF in this study, we attempt to provide some evidence that PLC plays a role in nerve regeneration itself and regeneration related to PEMF through the analysis of the difference between fucntional recovery group and non-recovery group in the recurrent laryngeal nerve. Materials and Method : Using 32 healthy male Sprague-Dawley rats, transections and primary anastomosis were performed on their left recurrent laryngeal nerves. Rats were then randomly assigned to 2 groups. The experimental group(n=16) received PEMS by placing them in custom cages equipped with Helm-holz coils(3hr/day, 5days/wk, for 12wk). The control group(n=16) were handled the same way as the experimental group, except that they did not receive PEMS. Laryngo-videoendoscopy was performed before and after surgery and followed up weekly. Laryngeal EMG was obtained in both PCA and TA muscles. Immunohistochemisty staining and Western blotting analysis using monoclonal antibody was performed to detect PLC-${\gamma}$1 in recurrent laryngeal nerve and nodose ganglion. Results : 10 rats(71%) in experimental group and 4 rats(38%) in the control group showed recovery of vocal fold motion. Functionally-recoverd rats show PLC-${\gamma}$1 positive cells in neuron and ganglion cells after 12 weeks from nerve injury. Conclusion : This study shows that PLC1-${\gamma}$ involved in singnal trasduction pathway in functinal recovery of injured recurrent laryngeal nerve and PEMF enhance the functional recovery by effect on this molecule.

• Toxicological Research
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• v.15 no.1
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• pp.79-87
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• 1999

To know the stress response and antioxidative effect of sulfur containing compounds, we observed the expression of the stress protein (heat shock protein; inducible protein) from mouse tissues and evaluated the protective effects to hydroxyl radical in mouse brain cell culture. Cysteine, methionine or sodium sulfide was fed by oral administration of 1 ml/per 6hr/three times with 1 mM, 2mM or 3mM to mouse, respectively. After that, the stress proteins were extracted from mouse tissues and analyzed the features of expression. The stress proteins by sulfur containing compounds were showed different aspects in the kinds and concentrations of their compounds, and in the tissues of mouse. In the liver, the stress proteins were appeared at different time on the concentration of sulfur containing compounds and had less than 20 KDa as small molecules. In general, the molecular weights of stress protein in liver, the stress proteins were appeared at different time on the concentration of sulfur containing compounds and had less than 20 KDa as small molecules. In general, the molecular weights of stress protein in the spleen were evaluated from 32KDa to 50KDA, and the induced times were relatively late at high concentration of cysteine, early at low concentration of methionine or sodium sulfide. The stress proteins in mouse muscle were detected mostly between 24hr after treatment of sulfur containing compounds. Their molecular weights were 15~24KDa. In the antioxidative effects of sulfur containing compounds to hydroxyl radical, cell viabilities were measured by 63.2% at 10 $\mu\textrm{M}$, 65.5% at 50 $\mu\textrm{M}$, 68.6% at 100 $\mu\textrm{M}$, 78.3% at 150 $\mu\textrm{M}$, or 83.0% at 200 $\mu\textrm{M}$ of cysteine, respectively. At addition of methionine, the cell viabilities were assessed as 58.1% at 10 $\mu\textrm{M}$, 62.8% at 50 $\mu\textrm{M}$, 75.7% at 100 $\mu\textrm{M}$, 78.6% at 150 $\mu\textrm{M}$, and 79.2% at 200 $\mu\textrm{M}$ after 4hrs exposure with 20mU/ml glucose oxidase (GO) system, while the numbers of live cells to hydroxyl radicals in treatment of sodium sulfide were showed 48.6% at 10 $\mu\textrm{M}$, 54.8% at 100 $\mu\textrm{M}$, 51.8% at 150 $\mu\textrm{M}$, and 51.6% at 200 $\mu\textrm{M}$ in the neuronal cells. In the inhibitory effects on the proliferation of tumor cells, percentages of dead cells of the CT-26 or HeLa cell were generally less than 30% even 48hr after addition of sulfur containing compounds. Conclusively, the results of these experiments indicate that stress protein by sulfur containing compounds can be used as physiological indicator for animal nutrition and for environment, and also that cysteine and methionine can play critical roles as an antioxidant.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1565-1570
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• 2016

Background: Central neurocytomas are rare neuronal neoplasms with a favorable prognosis. They are typically located in the lateral ventricles of the brain and mostly histologically correspond to WHO grade II with a Mib 1 labelling index of <2%. Similar tumors located in the cerebral hemispheres and spinal cord, for example, are called "extraventricular neurocytomas". A few tumors histologically show atypia, mitoses, vascular proliferation and/or necrosis and a Mib 1 index >2 % and are designated as "atypical neurocytomas. Aim: The aim of our study was to describe the common as well as unusual morphologic features and the role of various immunohistochemical stains in the diagnosis of these rare tumors. Materials and Methods: We retrieved and reviewed 35 cases diagnosed between 2001 and 2015. Results: Sixty percent of patients were males, and the mean age was 26 years. 31 cases (88.6%) were intraventricular and 4(11.4%) were extraventricular. Histologically, 6 cases (17.1%) were compatible with "atypical neurocytomas". All cases showed the classic morphology comprising nests and sheets of uniform, round cells with uniform round to oval nuclei with finely speckled chromatin and perinuclear cytoplasmic clearing (halos). All cases also showed delicate, fibrillary, neuropil-like matrices. Other common histologic features included capillary-sized blood vessels in a branching pattern in 57.1%, foci of calcification in 34.3% and perivascular pseudorosettes in 20%. Rare findings included Homer-Wright or true rosettes in 8.6% and ganglioid cells in 2.9%. Synaptophysin was the most consistent and valuable marker, being positive in almost all cases. GFAP positivity in tumor cells was seen in 25.7% of cases. Follow up was available in 13 patients. Of these 9 had histologically typical and 4 had atypical tumors. Only 1 (with an atypical neurocytoma) died, probably due to complications of surgery within one month, while 12 (including 3 with atypical neurocytomas) remained alive. Recurrence developed in 1 of these 12 patients (histologically consistent with typical morphology) almost 9 years after surgery. Only 4 patients, including 2 with atypical tumors, received postoperative radiotherapy, all with surgery in 2010 or later. Overall, prognosis was excellent with prolonged, recurrence free survival and most patients, even without receiving radiation therapy, were alive and well for many years, even a decade or more after surgery, without developing any recurrence, indicating the benign nature of these neoplasms.

• Journal of Life Science
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• v.29 no.12
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• pp.1329-1336
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• 2019

Subventricular zone (SVZ) in the brain contains neural stem cells (NSCs) which self-renew and differentiate to neurons and glial cells during postnatal period and throughout adulthood. Since fate decision to either proliferation or differentiation has to respond to intracellular and extracellular conditions, many intrinsic and extrinsic factors are involved. Among them, mitochondria have been reported to participate in fate decision of NSCs. In our previous report, we showed that long-term treatment of a mitochondrial inhibitor rotenone greatly inhibited neurogenesis. In this study, we examined the effects of short-term treatment of rotenone on SVZ NSCs. We found that (1) even one-day treatment of rotenone significantly reduced neurogenesis and earlier time points seemed to be more sensitive to rotenone, (2) a number of Mash1+ transit amplifying cells was decreased by one-day treatment of rotenone, (3) short-term treatment of rotenone eliminated most of the differentiated Tuj1+ neurons and Olig2+ oligodendrocytes, while glial fibrillary acidic protein (GFAP)+ astrocytes were not affected, and (4) sulfiredoxin 1 (Srxn1) gene expression was increased after one-day treatment of rotenone, indicating activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway. All these results confirm that functional mitochondria are necessary during differentiation to neurons or oligodendrocytes as well as maintenance of neurons after differentiation. Also, these data suggest that temporary exposure to mitochondrial inhibitor such as rotenone might have long-term effects on neurogenic potential of NSCs.

• Journal of Life Science
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• v.23 no.12
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• pp.1532-1540
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• 2013

T-box transcription factor 2 (Tbr2) is a member of the T-box family of transcription factors and it plays an important role in brain development, progenitor cell proliferation, and the modulation of differentiation and function in immune cells, such as CD8+ T cells and natural killer cells. This study aims to elucidate the involvement of Tbr2 in the pathophysiological events following pilocarpine-induced status epilepticus in mice. Status epilepticus resulted in prominent neuronal cell death in discrete brain regions, such as CA3, the hilus, and the piriform cortex. Interestingly, when the immunoreactivity of Tbr2 was examined two days after status epilepticus, it was transiently increased in CA3 and in the piriform cortex. Tbr2-positive cells in CA3 and the piriform cortex were double-labeled with CD11b, a marker of microglia and a subset of white blood cells, such as monocytes, CD8+ T cells, and natural killer cells. Moreover, the double-labeled cells with Tbr2 and CD11b showed amoeboid morphology, and this data indicates that Tbr2-expressing cells may be reactive microglia or infiltrating white blood cells. Furthermore, clustered Tbr2-positive cells were observed in the platelet endothelial cell adhesion molecule-1 (PECAM-1)-positive blood vessels near the CA3 area, which suggests that Tbr2-positive cells may be infiltrating the white blood cells. Based on this data, this study is the first to indicate the involvement of Tbr2 in neuropathophysiology in status epilepticus.

• Journal of Veterinary Clinics
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• v.11 no.1
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• pp.485-505
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• 1994

Lead toxicity was evaluated in forty-five cats on a balanced diet, treated with 0(control), 10, 100(low), 1, 000, 2, 000 and 4, 000(high)ppm of lead acetate orally on a body weight basis. The objectives were to describe the gross and histopathologic changes and to demonstrate what tissue lead concentrations correlate with the known dosages of lead. In subclinical lead toxicity, greater than 80% of the absorbed lead was deposited in the bone, whereas in more acute lead toxicity, 42% of absorbed lead was deposited in the bone and 36% and 20% of absorbed lead was deposited in the kidneys and in the liver, respectively. No gross lesions were found in the nervous system. Yellow-brown colored livers appear to be associated with lead toxicity. Neuronal necrosis in the cerebrum was the most predominant histopathologic finding. Astrocytic proliferation in the cerebral gray matter was observed in 1 high dose cat. Gliosis was noted in the cerebral cortex of 6 high dose cats. Two high dose cats had demyelination in the deepest layer of the cortical gray matter of the cerebrum. Extravasation of red cells and cavitation around the vessels were found in the cerebrum of 1 high dose cat. Six high dose cats had degeneration of Purkinje cells in the cerebellum. The microscopic findings in the peripheral nerves were ambiguous. In more acute toxicity, the cats had lead inclusions in the epithelial cells of proximal tubules of the kidneys of 7 cats and hepatocytes of the liver of S cats. These inclusions could be seen wlth H&E, but were more prominent with orcein staining. Two high dose cats had granulomas and connective tissue hyperplasia between tubules of the kidneys. Periportal hepatocyte vacuolization was observed in the liver of 22 cats. Vacuolization of seminiferous tubules and a reduced number of spermatogonia(indicative of reduced spermatogenesis) were found in the testis of 5 treated cats. Cystic ovaries were observed in 3 high dose cats and poor development of oogonia was found in 2 cats. The diagnosis of lead toxicity in cats can be suspected on the basis of the histopathologic lesions described, and can be of value in contributing to a diagnosis. A reliable diagnosis of lead poisoning can be helped utilizing tissue lead analysis(post molten)

• Journal of Life Science
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• v.19 no.1
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• pp.21-33
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• 2009

In this study, we investigated the effect of Rhei Rhizoma (RR; 大黃) water extract on gene expression in a hypoxia model of cultured rat hippocampal neurons. RR water extract $(2.5{\mu}g/ml)$ was added to the culture media on day 10 in vitro (DIV10), and a hypoxic shock (2% $O_2$/5% $CO_2$, $37^{\circ}C$, 3 h) was given on DIV13. After maintaining the cultures in normoxia for 24 hr, total RNA was isolated and used for microarray analysis. The MA-plot indicated that most genes were up- or downregulated within 2-fold. There were more downregulated genes (725 ea) than upregulated ones (472 ea) when larger than Global M value 0.2 (i.e., >15% increase) or smaller than Global M value -0.2 (i.e., >15% decrease) were considered. Antiapoptosis genes such as Tegt (2.4-fold), Nfkb1 (2.4-fold) Veg (1.8-fold), Ngfr (1.6-fold) were upregulated, while pro-apoptosis genes such as Bad (-64%), Cstb (-66%) were downregulated. Genes for combating environmental stress (stress response genes) such as Defb3 (2.7-fold), Cygb (2.2-fold), Ahsg (2.18-fold), Alox5 (2-fold) were upregulated. Genes for cell proliferation (cell cycle-related genes) such as Erbb2 (1.84-fold), Mapk12 gene (1.8-fold) was upregulated. Therefore, RR water extracts upregulate many pro-survival genes while downregulating many pro-death genes. It is interpreted that these genes, in combination with other regulated genes, can promote neuronal survival in a stress such as hypoxia.

• Applied Microscopy
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• v.35 no.3
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• pp.121-128
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• 2005

It has been known that ras signaling transduction leads to cell proliferation and migration including various adaptor molecules. Dynamin protein has been implicated in the formation of nascent vesicles in both the endocytic and secretory pathways. Dynamin was classified into three isoforms: dynamin I is only expressed in neuronal tissue, dynamin II is expressed ubiquitously in all tissue but that of dynamin III is confined to testis. We have reported in previous study that Grb2, binding to ras, was associated with dynamin II in NIH3T3 cells. Therefore we have tried to identify the relative expression of dynamin II according to overexpressed ras protein in ras oncogene transfected cells (NIH3T3 (ras)). For the detection of differential expression of dynamin II, we have used immunofluorescent staining and western blot methods in NIH3T3 and NIH3T3 (ras) cells. Next we have described the morphological differences between NIH3T3 and NIH3T3 (ras) cells using SEM and TEM. From these experiments dynamin II was highly expressed in NIH3T3 (ras) cells. NIH3T3 cells was transformed to more spindle shape with many cell process by transfection of ras oncogene. Moreover dynamin II was more concentrated in endocytotic membrane of the NIH3T3 (ras) cells compared to that of NIH3T3 cells. The present results suggested that dynamin II may involve the intermediate messenger in Ras signaling transduction pathway.

• Applied Microscopy
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• v.41 no.2
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• pp.109-116
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• 2011

Polycystic ovary syndrome (PCOS) is hormonal imbalance condition as the endocrine and metabolic disorder that induces the infertility and various complications in reproductive age women. Estradiol valerate (EV) is used hormone replacement therapy in menopausal women and is reported that excessive administration of EV induces the PCOS. Nerve growth factor (NGF) is the factor to regulate the survival and maturation of developing neuronal cell and is also synthesized in ovary. And NGF is overexpressed in EV-induced polycystic ovary (PCO) as previously reported. Therefore, this study examined the possibility of NGF as can be used the biological marker in diagnosis of PCOS, the hormonal imbalance condition, using PCO and CHO (chinese hamster ovarian) cell lines. The concentration of EV treatment is optimized a 1 mg as not influence on the proliferation of CHO cell but 2 mg and 3 mg of EV treatment have the inhibition effect at initial stage. The morphological change was not observed in CHO cell after dose dependent manner treatment of EV. Expression of NGF mRNA and protein is significantly increased at 30 min after EV treatment in CHO cells compared to that of control. And NGF protein expression is strongly increased in PCO tissue, which observed many follicular cysts compared to normal ovary tissue. Taken together, overexpression of NGF may be act as a molecule to induce an abnormal development of follicle, suggesting that NGF can be used as a biological marker in diagnosis of PCOS.