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91.

Background

Abnormalities of bone metabolism may be involved in the pathogenesis of ossification of the posterior longitudinal ligament (OPLL) of the spine. Besides its hemostatic effect, vitamin K epoxide reductase complex subunit 1 (VKORC1) plays a pivotal role in bone mineralization. The aim of this study is to investigate whether single nucleotide polymorphisms (SNPs) of the VKORC1 gene are associated with the occurrence of OPLL in a Korean population.

Method

A total of 98 patients with OPLL and 200 controls were genotyped for the VKORC1-1639G>A SNP (rs9923231) by polymerase chain reaction and restriction fragment length polymorphism analysis. All the patients (n?=?98) in this study underwent surgery (60, posterior-only approach; 36, anterior-only approach; 2, combined anterior and posterior approach) during their admission. We analyzed this association separately according to the gender and OPLL subgroup: OPLL continuous group (continuous type plus mixed type) and OPLL segmental group (segmental and localized type).

Results

We found that the genotype VKORC1-1639G>A frequency was significantly associated with the occurrence of the OPLL in the female group (adjusted odds ratio?=?5.22, 95 % confidence interval: 1.675 to 16.269, p?=?0.004). However, there was no overall association between the OPLL susceptibility and VKORC1-1639G>A polymorphism. A subgroup analysis did not show any significant correlation between VKORC1-1639G>A polymorphism and subgroup of OPLL either.

Conclusion

Our results suggest that the VKORC1-1639G>A SNP may increase susceptibility to OPLL in women. However, there was only a statistical association in the female group despite a number of stratified analyses. Therefore, the findings should be interpreted with caution, and further genetic study is needed to improve our understanding of the role of VKORC1 polymorphisms in determining the risk of OPLL occurrence.  相似文献   
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Formation of a femoral artery pseudoaneurysm is not infrequent after femoral arterial access. We successfully treated a pseudoaneurysm of the femoral artery using the StarClose vascular closure system. Closing device can be an alternative option for the treatment of pseudoaneurysm. © 2011 Wiley Periodicals, Inc.  相似文献   
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Colorectal cancer is the second most common cancer in males and the fourth most common in females in Korea. Since the most of colorectal cancer occur through the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. Korean Multi-Society Take Force developed the guidelines with evidence-based methods. Parts of the statements drawn by systematic reviews and meta-analyses. Herein we discussed the epidemiology of colorectal cancers and adenomas in Korea, optimal screening methods for colorectal cancer, and detection for adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations.  相似文献   
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For InP-based QDs, the current technology does not outperform CdSe-based QDs in many respects, one of which is stability. The optical stability of QDs is closely related to their surface properties, so QDs often use organic ligands for surface protection. These organic ligands are dynamically attached and detached on the QD surface; during detachment, their surfaces are easily damaged and oxidized, thereby deteriorating their optical characteristics. Therefore, we have synthesized a ligand 1,2-hexadecanedithiol with a bidentate form, inducing one ligand to bind to the QD surface strongly through the chelate effect, as a good way to improve the stability of the QDs; thus, the PL stability of the green-light-emitting InP-based QDs was greatly increased. To confirm the existence of the dithiol ligand, we used thermogravimetric analysis/simultaneous thermal analysis-mass spectroscopy (TGA/STA-MS). After that, we applied the ligand to blue-light-emitting ZnSe QDs and red-light-emitting InP QDs, and for those two types of QD we also confirmed that the stability was increased. Additionally, we tested dithiol exchanged QDs at a high temperature of 150 °C, and the increase of stability was effective even in a high temperature condition.

For InP-based QDs, the current technology does not outperform CdSe-based QDs in many respects, one of which is stability.  相似文献   
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The halophilic bacterium Pseudoalteromonas phenolica is well known as a promising candidate that enables the recycling of organic wastes at high salinity. However, for industrial applications of P. phenolica further research is required to explore the biological mechanism for maximizing the activities and productivities of this bacterium. In this study, we investigated the osmotic stress resistance and specific protease activities of P. phenolica in a normal-salt medium (0.3 M NaCl) and high-salt medium (1 M NaCl) based on intra- and extracellular multi-omics approaches. Proteins related to betaine and proline biosynthesis were increased under high salt stress. The targeted metabolite analysis found that proline was overproduced and accumulated outside the cell at high salinity, and betaine was accumulated in the cell by activation of biosynthesis as well as uptake. In addition, extracellular serine proteases were shown to be upregulated in response to salt stress by the extracellular proteomic analysis. The specific proteolytic activity assay indicated that the activities of serine proteases, useful enzymes for the recycling of organic wastes, were increased remarkably under high salt stress. Our results suggest that betaine and proline are key osmoprotectant metabolites of P. phenolica, and they can be used for the improvement of protease production and P. phenolica activities for the recycling of high-salt organic wastes in the future.

Multi-omics study showed the osmoprotective mechanism and changes of proteolytic activities of Pseudoalteromonas phenolica in response to salt stress.  相似文献   
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