Chitin-fibroin-hydroxyapatite membrane for guided bone regeneration: micro-computed tomography evaluation in a rat model / 대한악안면성형재건외과학회지

BACKGROUND: In guided bone regeneration (GBR) technique, many materials have been used for improving biological effectiveness by adding on membranes. The new membrane which was constructed with chitin-fibroin-hydroxyapatite (CNF/HAP) was compared with a collagen membrane (Bio-Gide®) by means of micro-computed tomography. METHODS: Fifty-four rats were used in this study. A critical-sized (8 mm) bony defect was created in the calvaria with a trephine bur. The CNF/HAP membrane was prepared by thermally induced phase separation. In the experimental group (n = 18), the CNF/HAP membrane was used to cover the bony defect, and in the control group (n = 18), a resorbable collagen membrane (Bio-Gide®) was used. In the negative control group (n = 18), no membrane was used. In each group, six animals were euthanized at 2, 4, and 8 weeks after surgery. The specimens were analyzed using micro-CT. RESULTS: Bone volume (BV) and bone mineral density (BMD) of the new bone showed significant difference between the negative control group and membrane groups (P < 0.05). However, between two membranes, the difference was not significant. CONCLUSIONS: The CNF/HAP membrane has significant effect on the new bone formation and has the potential to be applied for guided bone regeneration.

Hepatotoxicity and nephrotoxicity of gallotannin-enriched extract isolated from Galla Rhois in ICR mice / 한국실험동물학회지

To evaluate the hepatotoxicity and nephrotoxicity of Galla Rhois (GR) toward the liver and kidney of ICR mice, alterations in related markers including body weight, organ weight, urine composition, liver pathology and kidney pathology were analyzed after oral administration of 250, 500 and 1,000 mg/kg body weight/day of gallotannin-enriched extract of GR (GEGR) for 14 days. GEGR contained 68.7+/-2.5% of gallotannin, 25.3+/-0.9% of gallic acid and 4.4+/-0.1% of methyl gallate. Also, the level of malondialdehyde (MDA), a marker of lipid peroxidation, was decreased with 19% in the serum of high dose GEGR (HGEGR)-treated mice. The body and organ weight, clinical phenotypes, urine parameters and mice mortality did not differ among GEGR-treated groups and the vehicle-treated group. Furthermore, no significant increase was observed in alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), blood urea nitrogen (BUN) and the serum creatinine (Cr) in the GEGR-treated group relative to the vehicle-treated group. Moreover, the specific pathological features induced by most toxic compounds such as CCl4 were not observed upon liver and kidney histological analysis. Overall, the results of the present study suggest that GEGR does not induce any specific toxicity in liver and kidney organs of ICR at doses of 1,000 mg/kg body weight/day, indicating that this is no observed adverse effect level (NOAEL).

Comparative study of chitosan/fibroin-hydroxyapatite and collagen membranes for guided bone regeneration in rat calvarial defects: micro-computed tomography analysis / 国际口腔科学杂志·英文版

This study aimed to utilize micro-computed tomography (micro-CT) analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite (CFB-HAP) or collagen (Bio-Gide) membranes. Fifty-four (54) rats were studied. A circular bony defect (8 mm diameter) was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group (n=18), the CFB-HAP membrane was used to cover the bony defect, and in the control group (n=18), a resorbable collagen membrane (Bio-Gide) was used. In the negative control group (n=18), no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume (BV) and bone mineral density (BMD) (P<0.05) between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration (GBR) membrane.

Sendai F/HN Viroplexes for Efficient Transfection of Leukemic T Cells

PURPOSE: Most chemical transfection reagents are ineffective for the transfection of cells in suspension, such as leukemic cell and stem cell lineages. We developed two different types of viroplexes, cationic Sendai F/HN viroplexes (CSVs) and protamine sulfate-condensed cationic Sendai F/HN viroplexes (PCSVs) for the efficient transfection of T-leukemic cells. MATERIALS AND METHODS: The viroplex systems were prepared by reconstitution of fusogenic Sendai F/HN proteins in DMKE (O,O'-dimyristyl-N-lysyl glutamate) cationic liposomes. The viroplexes were further optimized for plasmid DNA and siRNA delivery to suspension cells. The particle size and surface charge of the viroplexes were analyzed with a zeta-sizer. Transfection of plasmid DNA (pDNA) and small interfering RNA (siRNA) by CSVs or PCSV was evaluated by measurement of transgene expression, confocal microscopy, FACS, and RT-PCR. RESULTS: The optimized CSVs and PCSVs exhibited enhanced gene and siRNA delivery in the tested suspension cell lines (Jurkat cells and CEM cells), compared with conventional cationic liposomes. In the case of pDNA transfection, the CSVs and PCSVs show at least 10-fold and 100-fold higher transgene expression compared with DMKE lipoplexes (or lipofectamine 2000), respectively. The CSVs showed more effective siRNA delivery to the suspension cells than cationic liposomes, as assessed by confocal microscopy, FACS, and RT-PCR. The effective transfection by the CSVs and PCSVs is presumably due to fusogenic activity of F/HN proteins resulting in facilitated internalization of pDNA and siRNA. CONCLUSION: This study suggests that Sendai F/HN viroplexes can be widely applicable for the transfection of pDNA and siRNA to suspension cell lines.

Altered expression of gamma-secretase components in animal model of major depressive disorder induced by reserpine administration / 한국실험동물학회지

Altered expression of neurotrophic factors as well as neuroinflammation is commonly associated with Major depressive disorder (MDD) and Alzheimer's disease (AD). To investigate whether or not reserpine-induced MDD affects the expression of AD-related proteins, the expression of gamma-secretase components and substrate were measured in brains of ICR mice following reserpine treatment for 15 days. In active avoidance test, total response time and peak slightly increased in the 2 mg/kg reserpine (RSP2)-treated group compared to vehicle-treated group (P<0.05). Expression and phosphorylation of MKP-1, which is a key factor in MDD pathology, were both higher in the RSP2-treated group than the vehicle- and 1 mg/kg reserpine (RSP1)-treated groups (P<0.02). Furthermore, full-length expression of amyloid precursor protein (APP) was enhanced in the RSP1 and RSP2-treated groups compared to the vehicle-treated group, whereas expression of gamma-secretase components decreased (P<0.03). Among the three components of the gamma-secretase complex, nicastrin protein underwent the largest decrease in expression, as detected by Western blotting (P<0.03). Therefore, the data presented here provide additional evidence about the pathological correlation between MDD and AD.

Peroxiredoxin I regulates the component expression of gamma-secretase complex causing the Alzheimer's disease / 한국실험동물학회지

Peroxiredoxin I (Prx I) is a member of the peroxiredoxins (Prxs) family, which are antioxidant enzymes that regulate various cellular process via intracellular oxidative signal pathways. In order to investigate the correlation between Prx I and the gamma-secretase complex, which causes Alzheimer's disease (AD), the expression level of Prx I was firstly evaluated in an animal model for AD. NSE/hPen-2 transgenic (Tg) mice, which were used as animal model in this study, showed a high level of Pen-2 expression and accumulation of Abeta-42 peptides in the hippocampus of brain. The expression level of Prx I was significantly higher on the mRNA and protein level in the brain of this model, while not change in Prx VI expression was observed. Furthermore, to verify the effect of Prx I on the gamma-secretase components in vitro, the expression level of these components was analyzed in the Prx I transfectants. Of the components of the gamma-secretase complex, the expression of PS-2 and Pen-2 was lower in the transfectants overexpressing Prx I compared to the vector transfectants. However, the expression of APP, NCT and APH-1 did not change in Prx I transfectants. Therefore, these results suggested that the expression of Prx I may be induced by the accumulation of Abeta-42 peptides and the overexpression of Prx I in neuroblastoma cells may regulate the expression of gamma-secretase components.

Topical Application of Selenium Can Significantly Relieve UV-induced Skin Aging in Hairless Mice / 한국실험동물학회지

Ultraviolet (UV) irradiation is an environmental factor that causes skin aging, and is also a major factor leading to cumulative alterations of skin structure, function and appearance. To investigate the effects of Selenium (Sel) on UV-induced skin aging, hairless mice were treated for 4 weeks with UV irradiation and topical application of Sel. Then, the effects of Sel were measured in the skin of these mice via histological analysis and Western blotting. According to the results of wrinkle formation analysis, the topical application of Sel induced a reduction in wrinkling formation in the damaged skin of the UV-irradiated mice. Additionally, our histological analysis demonstrated that the skin thickness in the Sel-treated group was less than in the UV-irradiated group. Furthermore, in an effort to investigate the mechanisms underlying the effects of Sel, the expression levels of matrix-metalloproteinase (MMP) and MAPK protein were assessed in both groups. The application of Sel induced a reduction in MMP-1 expression levels to the levels observed in the non-irradiated group. However, the expression level of MMP-9 was increased slightly in the Sel application group as compared with the vehicle application group. Additionally, the levels of ERK phosphorylation were increased by the application of Sel, but the levels of JNK and p38 were not altered by Sel treatment. These results suggest the possibility that Sel should be considered as a skin aging-protective and therapeutic drug candidate, which functions via the regulation of MMP expression levels.

The Bone Grinding and Scaffold Grafting Techniques for Guide Bone Regeneration Induce the Stress on the Rat Brain / 한국실험동물학회지

Guided bone regeneration (GBR) is a technique that a barrier membrane is placed over the bone defect to prevent the cell growth from the connective tissue and epithelium. In this study, in order to determine whether GBR technique could induce stress in rats, the standardized bone defect in rat calvaria was covered with apatitte membrane. Bone and brain tissues were collected from rats at 3 days, 2, 4, and 16 weeks post-operation, and then alteration of the new bone formation at the defects and stress-related factors were detected with histological examination and Western blot, respectively. From 4 to 16 weeks after the operation, the apatitte membrane was attached to the region of regenerated bone and encapsulated with a thick fibrous layer. Furthermore, the concentration of cortisol, a good indicator of stress, significantly increased 3 days post-operation. However, the increase at 3 days was returned to the basal level in 2 weeks. In Western blot analysis, the highest phosphorylation level of extracellular signal-regulated kinase (ERK) was observed 3 day post-operation, while those of the c-jun N-terminal kinase (JNK) and p38 were detected 4 weeks post-operation. Taken together, the results suggest that GBR technique may induce the serious stress on the brain tissue via the induction of ERK phosphorylation during 2 weeks, and that the stress responses restored in 4 week via JNK and p38 signaling pathway.

A Case of Urachal Actinomycosis / 대한비뇨기과학회지

No abstract available.

A Case of Urachal Actinomycosis / 대한비뇨기과학회지

No abstract available.

Spontaneous Retroperitoneal Hematoma due to Liver Cirrhosis: A Case Report / 대한간학회지

Spontaneous retroperitoneal hemorrhage due to liver cirhosis associated with impaired coagulopathy is very rare disease. Spontaneous retroperitoneal hemorrhage has been recorded as having originated from many retroperitoneal organs and blood vessels, and it may be due to local disease and/or systemic factors. In the majority of patients the bleeding arose from the kidney or adrenal gland. Among the systemic causes of spontaneous retroperitoneal hemorrhage are anticoagulation therapy and chronic hemodialysis during the course of which hemorrhagic complications may occur at many site, including the retroperitoneal space. Blood dyscrasias have been a rare cause of spontaneous retroperitoneal hemorrhage. Conditions reported have been included hemophilia, leukemia, polycythemia and sickle cell trait. Virtually every hemostatic function may be impaired in patients with severe hepatic disease as the result of failure of both the biosynthetic and clearence function of the liver, thrombocytopenia, platelet dysfunction, intravascular coagulation and fibrinogenolysis, and the effects of products of fibrinogen catabolism on the coagulation mechanism. We are reporting a case of spontaneous retroperitoneal hematoma in a patient with alcoholic liver cirrhosis with brief review of literature.

Acute Myocardial Infarction in Patient with Spontaneous Coronary

Spontaneous coronary artery dissection is a rere incident occurring usually in young patients, predominautly in females. It is usually fatal and found postmortem. It is also a rare cause of acute myocardial infarction. We present the case of a twenty nine-year-old-man with spontaneous right coronary artery dissection found angiographically which caused an inferior wall myocardial infarction. He was treated with medical therapy only amd after uneventful hospital course, he was discharged with medication. Three months later, coronary angiography was done to follow up the lesion and found that the site was completely healed.