802 research outputs found
Bone Union Rate Following Instrumented Posterolateral Lumbar Fusion: Comparison between Demineralized Bone Matrix versus Hydroxyapatite
Study DesignRetrospective study.PurposeTo compare the union rate of posterolateral lumbar fusion (PLF) using demineralized bone matrix (DBM) versus hydroxyapatite (HA) as bone graft extender.Overview of LiteratureTo our knowledge, there has been no clinical trial to compare the outcomes of DBM versus HA as a graft material for PLF.MethodsWe analyzed prospectively collected data from consecutive 79 patients who underwent instrumented PLF. Patients who received DBM were assigned to group B (n=38), and patients who received HA were assigned into group C (n=41). The primary study outcome was fusion rate assessed with radiographs. The secondary outcomes included pain intensity using a visual analogue scale, functional outcome using Oswestry disability index score, laboratory tests of inflammatory profiles and infection rate.ResultsOne year postoperatively, bone fusion was achieved in 73% in group B and 58% in group C without significant difference between the groups (p=0.15). There were no differences between the groups with respect to secondary outcomes.ConclusionsDBM would provide noninferior outcomes compared to the HA as a fusion material for PLF, and could be a notable alternative
Reliability and Diagnostic Accuracy of Standard Dermatomes and Myotomes for Determining the Pathologic Level in Surgically Verified Patients With Cervical Radiculopathy
Objective This study aimed to investigate the reliability and diagnostic accuracy of typical dermatomes and myotomes for determining the pathologic level in surgically verified patients with cervical radiculopathy. Methods Patients who underwent single-level surgery due to cervical radiculopathy with at least a 60% reduction in preoperative symptoms or recovery of muscle power after surgery were included. The observed clinical symptoms (pain, paresthesia, motor weakness) were compared to those of typical cervical dermatomes and myotomes. Results Among the 227 patients reviewed, 142 (62.6%) had a standard dermatomal pattern, and 74 of 110 (67.3%) had a standard myotomal pattern. The myotome of C5/6 radiculopathy showed much more variance than those of other cervical segments. Among the patients with severe motor weakness (muscle strength ≤ grade 3 or obvious muscle atrophy), all those with involvement of root C5, C7, and C8 showed a typical pattern (C4/5: 13 of 13 patients, C6/7: 5 of 5 patients, C7/T1: 3 of 3 patients), while only 2 of the 6 patients (33.3%) with severe motor weakness caused by C5/6 radiculopathy fit the typical pattern. Conclusion Among various symptoms, cervical myotome is of great value in determining the pathological level. However, it should be noted that there is high variability in human dermatomes and myotomes, especially for motor weakness due to C6 root compression, which is more variable than others
Multimodal route choice in maritime transportation: The case of Korean auto-parts exporters
Global offshoring has increased the need for transport of half-finished goods and components, along with finished goods. The auto-parts industry in Korea has also entered the global market as Korean car manufacturers have started to build overseas factories. Maintaining cost competitiveness by minimising total logistics costs will thus be a critical strategy for the industry. This research compares the total annual costs of four feasible transport routes from Korea to the US using the inventory-theoretic model, which encompasses direct transport costs, in-transit carrying costs, and warehouse inventory costs. We apply this model to real transport data collected from a Korean auto-parts company. A static analysis shows that inventory costs can play a decisive role in altering the cost competitiveness of different routes. In addition, sensitivity and scenario analyses with changes in variables and the market situations reveal that the cost structure of each routes plays an important role in determining their relative cost competitiveness in varying market conditions
Development of KAISTSAT-4 Expanding the Role of Small Satellite for Scientific Research
The fourth Korean small satellite, KAISTSAT-4, is under development by Satellite Technology Research Center (SaTReC) of the Korea Advanced Institute of Science and Technology (KAIST). The KAISTSAT-4 program was commenced on October 1998 with multiple mission objectives, which include exploring space science, deploying satellite-based data collection system and development of precision star sensor. Despite severe constraints on mass and size, these advanced science and engineering payloads are expected to deliver various useful results and exhibit the unique role of small satellite. We present an overview of the KAISTSAT-4 mission and describe its current status. Finally the prospect of future small satellite programs is briefly introduced
Frontal lobe epilepsy: Clinical characteristics, surgical outcomes and diagnostic modalities
SummaryObjectiveTo identify surgical prognostic factors and to characterize clinical features according to the location of the intracranial ictal onset zone of frontal lobe epilepsy (FLE) in order to assess the role of various diagnostic modalities, including concordances with presurgical evaluations.MethodsWe studied 71 FLE patients who underwent epilepsy surgery and whose outcomes were followed for more than 2 years. Diagnoses were established by standard presurgical evaluation.ResultsClinical manifestations could be categorized into six types: initial focal motor (9 patients), initial versive seizure (15), frontal lobe complex partial seizure (14), complex partial seizure mimicking temporal lobe epilepsy (18), initial tonic elevation of arms (11), and sudden secondary generalized tonic–clonic seizure (4). Thirty-seven patients became seizure-free after surgery. Five patients were deleted in the analysis because of incomplete resection of ictal onset zones. The positive predictive value of interictal EEG, ictal EEG, MRI, PET, and ictal SPECT, respectively were 62.5%, 56.4%, 73.9%, 63.2%, and 63.6%, and the negative predictive value were 46.0%, 44.4%, 53.5%, 44.7%, and 51.7%. No significant relationship was found between the diagnostic accuracy of these modalities and surgical outcome, with the exception of MRI (p=0.029). Significant concordance of two or more modalities was observed in patients who became seizure-free (p=0.011). We could not find any clinical characteristic related to surgical outcome besides seizure frequency. No definite relationship was found between the location of intracranial ictal onset zone and clinical semiology.ConclusionAlthough various diagnostic methods can be useful in the diagnosis of FLE, only MRI can predict surgical outcome. Concordance between presurgical evaluations indicates a better surgical outcome
bZIPDB : A database of regulatory information for human bZIP transcription factors
<p>Abstract</p> <p>Background</p> <p>Basic region-leucine zipper (bZIP) proteins are a class of transcription factors (TFs) that play diverse roles in eukaryotes. Malfunctions in these proteins lead to cancer and various other diseases. For detailed characterization of these TFs, further public resources are required.</p> <p>Description</p> <p>We constructed a database, designated bZIPDB, containing information on 49 human bZIP TFs, by means of automated literature collection and manual curation. bZIPDB aims to provide public data required for deciphering the gene regulatory network of the human bZIP family, e.g., evaluation or reference information for the identification of regulatory modules. The resources provided by bZIPDB include (1) protein interaction data including direct binding, phosphorylation and functional associations between bZIP TFs and other cellular proteins, along with other types of interactions, (2) bZIP TF-target gene relationships, (3) the cellular network of bZIP TFs in particular cell lines, and (4) gene information and ontology. In the current version of the database, 721 protein interactions and 560 TF-target gene relationships are recorded. bZIPDB is annually updated for the newly discovered information.</p> <p>Conclusion</p> <p>bZIPDB is a repository of detailed regulatory information for human bZIP TFs that is collected and processed from the literature, designed to facilitate analysis of this protein family. bZIPDB is available for public use at <url>http://biosoft.kaist.ac.kr/bzipdb</url>.</p
Adsorptive removal of CO2 from CO2-CH4 mixture using cation-exchanged zeolites
Raw natural gas and landfill gas contains methane as its major component, but it also contains considerable amounts of contaminants such as CO2 and H2S (i.e. acid gases) that can cause corrosion and fouling of the pipeline and equipment during transportation and liquefaction. Amine-based CO2 gas removal processes have been employed in the gas industry, but these processes have disadvantages including high regeneration energy requirements and inefficiencies; these issues have not been adequately solved to date. Currently, adsorptive acid gas removal technologies have received significant interest because of the simplicity of adsorbent regeneration by thermal or pressure variation1). Numerous micro- and mesoporous adsorbents including zeolites [2-3], titanosilicates[4], activated carbons[5-6], metal-organic-framework (MOF) [7], and silica-alumina materials[8-9] were studied for this type of application. However, the CO2/CH4 selectivity of the aforementioned adsorbents was not high enough for commercial applications.In this study, different cation-exchanged zeolites were synthesized, physicochemically characterized, and evaluated for adsorptive removal of CO2 from CO2-CH4 mixtures. The adsorption isotherms of CO2 and CH4 in the pressure and temperature ranges 0 − 3MPa and 10 – 40 oC, respectively, for different cation-exchanged zeolites were measured and compared. The ideal-adsorbed solution theory (IAST) was employed for the estimation of CO2/CH4 selectivity for the different cation-exchanged zeolites.
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Downregulation of protein kinase CK2 activity induces age-related biomarkers in C. elegans
Studies show that a decrease in protein kinase CK2 (CK2) activity is associated with cellular senescence. However, the role of CK2 in organism aging is still poorly understood. Here, we investigated whether protein kinase CK2 (CK2) modulated longevity in Caenorhabditis elegans. CK2 activity decreased with advancing age in the worms. Knockdown of kin-10 (the ortholog of CK2 beta) led to a short lifespan phenotype and induced age-related biomarkers, including retardation of locomotion, decreased pharyngeal pumping rate, increased lipofuscin accumulation, and reduced resistance to heat and oxidative stress. The long lifespan of age-1 and akt-1 mutants was significantly suppressed by kin-10 RNAi, suggesting that CK2 acts downstream of AGE-1 and AKT-1. Kin-10 knockdown did not further shorten the short lifespan of daf-16 mutant worms but either decreased or increased the transcriptional activity of DAF-16 depending on the promoters of the target genes, indicating that CK2 is an upstream regulator of DAF-16 in C. elegans. Kin-10 knockdown increased production of reactive oxygen species (ROS) in the worms. Finally, the ROS scavenger N-acetyl-L-cysteine significantly counteracts the lifespan shortening and lipofuscin accumulation induced by kin-10 knockdown. Therefore, the present results suggest that age-dependent CK2 downregulation reduces longevity by associating with both ROS generation and the AGE-1-AKT-1-DAF-16 pathway in C. elegans. © Copyright 2017 Elsevier B.V., All rights reserved.1111sci
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