Effects of Maxillary Sinus Graft on the Survival of Endosseous Implants: A 10-Year Retrospective Study

Purpose: The aim of this study was to determine the survival rates of implants placed in grafted maxillary sinuses and compare the results obtained with graft materials, implant surfaces and timing of implant placement. Materials and Methods: Between January 1996 and December 2005, 391 implants are placed in 161 patients who underwent sinus grafting treatment simultaneously or separately at Ewha Womans University Hospital. According to inclusion critieria, 272 impants were placed in 102 patients with 112 sinus grafts (30 females, 72 males), aged 26 to 88 years (mean age 49.0±9.7). The follow-up period ranged from 12 to 134 months (mean F/U 47±32). Survival rates were evaluated according to graft material, implant surface and timing of implant placement, The Kaplan-Meier procedure and the log rank (Mantel-Cox) test were used to estimate survival rates and test for equality of survival rates between different groups of patients. Results: Ten-year cumultative survival rate for implants placed in the grafted sinuses was 90.1%. The survival rates for autogenous bone, combination and bone substitutes were 94.6%, 85.9% and 100% respectively (p\u3e0.05). According to implant surface, survival rates were 84.8% in machined group and 97.5% in rough group (p0.05). Conclusion: Ten-year cumultative survival rate for implants placed in the grafter sinuses was 90.1% Rough-shaped implants have a higher survival rate than machined-surface implants when placed in grafted sinuses. (p\u3c0.05)

In-situ analysis of fiber structure development for isotactic polypropylene

Structural development of isotactic polypropylene (iPP) fibers was analyzed in real time through in-situ WAXD/SAXS and fiber temperature measurements during CO(2) laser-heated drawing because the CO(2) laser irradiation can nearly fix the necking position on the running fiber. The in-situ WAXD/SAXS measurements were carried out with a high time-resolution of 0.4 ms. The as-spun iPP fibers of two different initial structures were laser-heat-drawn to a draw ratio of 6.5. For the drawing of PP fiber containing mesophase structure, diffraction from the oriented mesophase remained until an elapsed time of 1.0 ms, when oriented alpha-phase crystal started to form. Meanwhile, for the drawing of PP fiber containing both an alpha-phase and a mesophase structure, fragmented microcrystals were reorganized by orientation-induced crystallization before an elapsed time of 1.0 ms. The long period increased drastically with fragmentation, and decreased with reorganization. The long period was about 16 nm for both drawn fibers.ArticlePOLYMER. 52(9):2044-2050 (2011)journal articl

Effect of drawing stress on mesophase structure formation of poly(ethylene 2,6-naphthalene dicarboxylate) fiber just after the neck-drawing point

The structural development of poly(ethylene 2,6-naphthalene dicarboxylate) (PEN) fibers was analyzed by in situ X-ray diffraction and fiber temperature measurements. The PEN fiber was drawn continuously under three drawing stresses, where the neck-drawing point was fixed accurately by CO2 laser irradiation heating. The developed crystal structures of the drawn fibers depended on the drawing stresses, that is, only the alpha-crystal was obtained under a drawing stress of 148 MPa, an alpha-rich mixed crystal was obtained for 54 MPa, and a beta-rich mixed crystal was obtained under 23 MPa stress. Fiber containing over 70% beta-crystal was obtained in the third case. Orientation-induced crystallization rates (K) and crystallization induction times (t(0)) were estimated for the three drawing stresses: K = 2210 s(-1) and t(0) = 0.5 ms for 148 MPa, K = 940 s(-1) and t(0) = 1.0 ms for 54 MPa, and K= 655 s(-1) and t(0) = 4.0 ms for 23 MPa. In addition, the drawing stress acted as a definitive influence not only on the resulting crystal form but also on the chain conformation of the mesophase structure. The d-spacing of the (001') diffraction increased with drawing stress, and the longer (001') spacing generated the alpha-crystal while the comparatively shorter (001') spacing yielded the beta-crystal. The d-spacings of 1.27 and 1.23 nm for the drawing stresses of 148 and 23 MPa, respectively, were somewhat shorter than the c-axis lengths of the alpha- and beta-crystals of 1.32 and 1.27 nm, respectively.ArticlePOLYMER. 53(19):4272-4279 (2012)journal articl

Protective Mechanism of KIOM-4 in Streptozotocin-Induced Pancreatic β-Cells Damage Is Involved in the Inhibition of Endoplasmic Reticulum Stress

Endoplasmic reticulum stress-mediated apoptosis plays an important role in the destruction of pancreatic β-cells and contributes to the development of type 1 diabetes. The present study examined the effect of KIOM-4, a mixture of four plant extracts, on streptozotocin- (STZ-) induced endoplasmic reticulum (ER) stress in rat pancreatic β-cells (RINm5F). KIOM-4 was found to inhibit STZ-induced apoptotic cell death, confirmed by formation of apoptotic bodies and DNA fragmentation. STZ was found to induce the characteristics of ER stress; mitochondrial Ca2+ overloading, enhanced ER staining, release of glucose-regulated protein 78 (GRP78), phosphorylation of RNA-dependent protein kinase (PKR) like ER kinase (PERK) and eukaryotic initiation factor-2α (eIF-2α), cleavage of activating transcription factor 6 (ATF6) and caspase 12, and upregulation of CCAAT/enhancer-binding protein-homologous protein (CHOP). However, KIOM-4 attenuated these changes induced by STZ. Furthermore, KIOM-4 suppressed apoptosis induced by STZ in CHOP downregulated cells using CHOP siRNA. These results suggest that KIOM-4 exhibits protective effects in STZ-induced pancreatic β-cell damage, by interrupting the ER stress-mediated pathway

Development of a fiber structure in poly(vinylidene fluoride) by a CO(2) laser-heated drawing process

Rapid and uniform heating by CO(2) laser radiation can fix the position where necking occurs. Therefore, this study investigated the development of a fiber structure in poly(vinylidene fluoride) in continuous drawing by in situ measurement using synchrotron X-ray radiation with a time resolution of several hundred microseconds. Two neck-deformation behaviors were observed in the laser drawing: a moderate neck deformation under low drawing stress and a steep neck deformation under high drawing stress. The low drawing stress resulted in a mixture of alpha- and beta-crystals in which the beta-crystal was formed within 1ms after the necking, earlier than the alpha-crystal. The development of the fiber structure under high drawing stress was almost complete in less than 1 ms, and the developed structure contained only beta-crystals. Small-angle X-ray scattering images showed meridional streaks at low drawing stress, whereas a four-pointed pattern occurred under high drawing stress. Low drawing stress generated a long periodic structure that was defective in the periodic regularity of crystalline and amorphous regions, although the molecular chains were nearly oriented along the fiber axis. The high drawing stress resulted in a well-packed structure of adjacent fibrils with alternating amorphous and crystalline regions. Polymer Journal (2010) 42, 657-662; doi: 10.1038/pj.2010.53; published online 23 June 2010ArticlePOLYMER JOURNAL. 42(8):657-662 (2010)journal articl

KIOM-4 Protects against Oxidative Stress-Induced Mitochondrial Damage in Pancreatic β-cells via Its Antioxidant Effects

The protective effect of KIOM-4, a mixture of plant extracts, was examined against streptozotocin (STZ)-induced mitochondrial oxidative stress in rat pancreatic β-cells (RINm5F). KIOM-4 scavenged superoxide and hydroxyl radicals generated by xanthine/xanthine oxidase and Fenton reaction (FeSO4/H2O2), respectively, in a cell-free chemical system. In addition, a marked increase in mitochondrial reactive oxygen species (ROS) was observed in STZ-induced diabetic cells; this increase was attenuated by KIOM-4 treatment. Mitochondrial manganese superoxide dismutase (Mn SOD) activity and protein expression were down-regulated by STZ treatment and up-regulated by KIOM-4 treatment. In addition, NF-E2 related factor 2 (Nrf2), a transcription factor for Mn SOD, was up-regulated by KIOM-4. KIOM-4 prevented STZ-induced mitochondrial lipid peroxidation, protein carbonyl and DNA modification. Moreover, KIOM-4 treatment restored the loss of mitochondrial membrane potential (Δψ) that was induced by STZ treatment, and inhibited the translocation of cytochrome c from the mitochondria to the cytosol. In addition, KIOM-4 treatment elevated the level of ATP, succinate dehydrogenase activity and insulin level, which were reduced by STZ treatment. These results suggest that KIOM-4 exhibits a protective effect through its antioxidant effect and the attenuation of mitochondrial dysfunction in STZ-induced diabetic cells

Cytoprotective Effect of Phloroglucinol on Oxidative Stress Induced Cell Damage via Catalase Activation

Abstract We investigated the cytoprotective effect of phloroglucinol, which was isolated from Ecklonia cava (brown alga), against oxidative stress induced cell damage in Chinese hamster lung fibroblast (V79-4) cells. Phloroglucinol was found to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydrogen peroxide (H 2 O 2 ), hydroxy radical, intracellular reactive oxygen species (ROS), and thus prevented lipid peroxidation. As a result, phloroglucinol reduced H 2 O 2 induced apoptotic cells formation in V79-4 cells. In addition, phloroglucinol inhibited cell damage induced by serum starvation and radiation through scavenging ROS. Phloroglucinol increased the catalase activity and its protein expression. In addition, catalase inhibitor abolished the protective effect of phloroglucinol from H 2 O 2 induced cell damage. Furthermore, phloroglucinol increased phosphorylation of extracellular signal regulated kinase (ERK). Taken together, the results suggest that phloroglucinol protects V79-4 cells against oxidative damage by enhancing the cellular catalase activity and modulating ERK signal pathway

A Case of Portal Vein Thrombosis by Protein C and S Deficiency Completely Recanalized by Anticoagulation Therapy

Portal vein thrombosis (PVT) is a rare form of venous thrombosis that affects the hepatic portal vein flow, which can lead to portal hypertension. Treatment of PVT includes anticoagulants, thrombolysis, insertion of shunts, bypass surgery, and liver transplantation. Single anticoagulation therapy is not regarded as a curative treatment but can be associated with a reduction in new thrombotic episodes. We experienced a case of acute total occlusion of PVT provoked by protein C and S deficiency syndrome. PVT was completely recanalized with oral anticoagulant therapy following low molecular weight heparin therapy