• The korean journal of orthodontics
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• v.32 no.2 s.91
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• pp.107-115
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• 2002

The aim of this study was to investigate experimentally the mechanical and histological effect of drilling process on the stability of micro-implant used for the orthodontic anchorage. For this purpose, 32 micro-implants(Osas$^{(R)}$, Epoch medical, ${\phi}$1.6 mm) were inserted into maxilla, mandible and palate in two beagle dogs. 16 micro-implants(8 per dog) were inserted after drilling with pilot drilling bur (drill method group). 16 micro-implants(8 per dog) were inserted without drilling (drill-free method group). After 1 week, micro-implants were loaded by means of Ni-Ti coil spring (Ni-Ti springs-extension$^{(R)}$, Ormco) with 200-300 gm force. Following 12 weeks, the micro-implants and the surrounding bone were removed. Before sacrifice, the mobilities were tested with Periotest$^{(R)}$(Siemens). Undecalcified serial sections with the long axis were made and the histologic evaluations were done. The results of this study were as follow ; 1. The osseointegration was found in both of drill-free method group and drill method group 2. Two of drill method group and one of drill-free method group in 32 micro-implants were lost after loading. 3. The mobilities of drill-free method group were less than drill method group 4. The bone contact on surface of micro-implants in drill-free method group was more than drill method group but there was no significant difference between groups. 5. The bone density in threads of micro-implants in drill-free method group was more than drill method group and there was significant difference between groups. These results suggest that drill-free method in insertion of micro-implants is superior to drill method on the stabilities, bone remodeling and osseointegrations under early loading.

• Tuberculosis and Respiratory Diseases
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• v.48 no.5
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• pp.757-765
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• 2000

Background : Angiogenesis plays a critical role in human tumor growth and metastasis. Microvessel count as a measure of tumor angiogenesis, has been significantly correlated with invasive and metastatic patterns in breast. prostate and cutaneous carcinomas. Materials and Methods : Fifty patients with curatively resected non-small cell lung cancer were evaluated. Tumor tissues embedded in paraffin block were stained by anti CD 31 (PECAM, platelet endothelial cellular adhesion molecule) using immunohistochemical method to assess microvessel count. Microvessels were counted in the most active areas of neovascularization(microscopy, 200$\times$). Results: 1) Mean microvessel count was 47.1$\pm$17.7(per 200$\times$field) in total 50 cases. 2) Mean microvessel count of adenocarcinoma (54.4$\pm$19.9) was significantly higher than that of squamous cancer (43.9$\pm$16.2) (p<0.05), but there were no relationship between microvessel count and TNM stages. 3) Median survival time, 2-year and 5-year survival rates of the low microvascular group (microvessel count<45, 22 cases) were 61 months, 80% and 40%, respectively, and those of the high microvascular group(microvessel count$\geq$45, 28 cases) were 46 months, 75% and 12%, respectively. As results, prognosis of low microvascular group is statistically significantly superior to that of the high microvascular group (p=0.0162, Kaplan-Meier, log-rank). Conclusion : Angiogenesis assessed by microvessel count can be used as one of the significant prognostic factors in non-small cell lung cancer.

• Applied Microscopy
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• v.38 no.3
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• pp.151-157
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• 2008

Trigeminal primary afferents expressing $P2X_3$ or transient receptor potential vanilloid 1 (TRPV1) are involved in the transmission of nociceptive information. In order to characterize $P2X_3$- and TRPV1-immunopositive neurons in the trigeminal ganglion (TG) and trigeminal caudal nucleus (Vc), we performed immunofluorescence experiments using anti-$P2X_3$ and anti-TRPV1 antisera and a morphometric analysis. 77.4% (1,401/1.801) of all the $P2X_3$-postive neurons coexpressed TRPV1 and 51.9% (1,401/2,698) of all the THFV1-immunopositive neurons also costained for $P2X_3$ in the TG. Immunoreactivity for both $P2X_3$ and TRPV1 were present in medium-sized neurons but not in small- and large-sized neurons. $P2X_3$ and/or TRPV1-immunopositive fibers were observed in the primary afferents and their associated axons in the Vc. These fibers and terminals were distributed in the superficial lamina of Vc: $P2X_3$-immunopositive fibers and terminals were distributed in the lamina I and II, expecially in the inner part of lamina II (lamina IIi), whereas TRPV1-immunopositive ones were densely detected in the lamina I and outer part of lamina II (lamina IIo). Immunopositive fibers and terminals for both $P2X_3$ and TRPV1 were observed on the border between lamina IIi and IIo. These results suggest that terminals coexpressing $P2X_3$ and TRPV1 are involved in specific roles in the transmission and processing of orofacial nociceptive information.

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.169-177
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• 2002

Purpose: Hypertension accelerates the progression of chronic renal disease, whether it results from, or causes, the renal disease. Therefore, the control of hypertension is one of the important factors that retard the rate of renal deterioration. We compared the effects of different antihypertensive agents on renal function and glomerular morphology In subtotal nephrectomized rats. Materials and methods: After induction of chronic renal failure with 5/6 nephrectomy, the rats were divided into three groups; control group (Group C), enalapril group (Group E), and nicardipine group (Group N). Systolic blood pressure was measured by tail cuff method every 4 weeks until 12 weeks after nephrectomy. At 12 weeks after nephrectomy, all rats were placed in metabolic cages for 24 hour urine collections to measure urinary protein and creatinine excretion. After urine collection and blood sampling for serum creatinine, all rats were sacrificed. The renal tissue was processed for morphometric study with light microscope and electron microscope. Results: 1. The blood pressure of Group C increased progressively, but both enalapril and nicardipine prevented the development of hypertension, and the two drugs were equally effective in maintaining normal blood pressure throughout the study. 2. Twenty-four hour urinary protein excretion was lower in Group E compared to Group C and Group N 3. Mesangial expansion score in both treated groups were significantly lower than the control group. Mean glomerular volume in Group E was significantly reduced compared to Group C and Group N. There was no significant difference in mean glomerular volume between Group C and Group N. 4. There was no significant difference in podocyte structural changes, estimated by filtration slit length density, among control, enalapril and nicardipine treated groups. Conclusion: Control of hypertension with enalapril or nicardipine afforded considerable protection from mesangial expansion in the rat remnant kidney model. But protein excretion and glomerular growth were significantly reduced in Group E compared to Group N. There was no significant difference in podocyte structural changes among the 3 groups.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.1-7
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• 2010

Purpose: The purpose of this study was to evaluate the fit of zirconia core using MAD/MAM system comparing to that of conventional metal-ceramic and CAD/CAM system. Materials and methods: Duplicating the prepared resin tooth, 50 improved stone dies were fabricated. These dies are classified as a group of 5 to create the core. The groups were composed of metal-ceramic, $Cercon^{(R)}$, $Ceramill^{(R)}$, $Rainbow^{TM}$, and $Zirkonzhan^{(R)}$. Each core was cemented to stone die, and then, absolute marginal discrepancy was measured with microscope at a magnification of ${\times}50$. Statistical analysis was done with one-way ANOVA test and Tukey's HSD test. Results: The mean absolute marginal discrepancy for metal-ceramic was $51.97{\pm}23.38{\mu}m$, for $Cercon^{(R)}$ was $62.16{\pm}25.88{\mu}m$, for $Ceramill^{(R)}$ was $67.64{\pm}40.38{\mu}m$, for $Rainbow^{TM}$ was $125.07{\pm}42.19{\mu}m$, and for $Zirkonzhan^{(R)}$ was $105{\pm}44.61{\mu}m$. Conclusion: 1. Fit of margin was identified as in the order of metal-ceramic, $Cercon^{(R)}$, $Ceramill^{(R)}$, $Zirkonzhan^{(R)}$, and $Rainbow^{TM}$. 2. Absolute marginal discrepancy of the zirconia core that designed by MAD/MAM system had significant differences in order of $Ceramill^{(R)}$, $Zirkonzhan^{(R)}$, and $Rainbow^{TM}$. 3. The mean absolute marginal discrepancy between $Cercon^{(R)}$ and $Ceramill^{(R)}$ did not show significant differences.