Recently autogenous nerve graft was usually used for segmental defect of peripheal nerve injury. In case of inappropriate size or amount of donor nerve graft, there were many studies included nerve regeneration with special nerve conduit material. To compare the result of autogenous nerve graft with that of silicone tubing method in segmental defect of sciatic nerve, the experiments were carried out on adult rats with autogenous nerve graft on the left side and silicone tubing on the right side. The results were as follows; 1. Myelinated nerve fibers were larger in silicone tubing method than autogenous nerve graft at postop. 4 weeks. 2. There was no difference in nerve regeneration in both groups at postop. 12 weeks. 3. Some atrophic changes were showed in denervated muscles in both groups at postop. 4 weeks. Skeletal muscle changes between the two groups were meagre. 4. Perineural adhension was rare in silicone tubing group in contrast to autogenous nerve graft group. 5. Nerve Conduction Velocity was similar between autogenous nerve graft and silicone tubing method after 4 weeks postoperatively. In conclusion, this study suggests that silicone tubing can be useful method to repair the large nerve gaps and has a potential clinical utilization in large segmental nerve defect.
Adult ; Animals ; Autografts ; Humans ; Methods ; Muscle, Skeletal ; Muscles ; Nerve Fibers, Myelinated ; Nerve Regeneration ; Neural Conduction ; Rats ; Sciatic Nerve ; Silicon ; Silicones ; Tissue Donors ; Transplants

Coronaviruses (CoVs) are single-stranded RNA viruses which contain the largest RNA genomes, and severe acute respiratory syndrome coronavirus (SARS-CoV), a newly found group 2 CoV, emerged as infectious disease with high mortality rate. In this study, we compared the synonymous codon usage patterns between the nucleocapsid and spike genes of CoVs, and C-type lectin domain (CTLD) genes of human and mouse on the codon basis. Findings indicate that the nucleocapsid genes of CoVs were affected from the synonymous codon usage bias than spike genes, and the CTLDs of human and mouse partially overlapped with the nucleocapsid genes of CoVs. In addition, we observed that CTLDs which showed the similar relative synonymous codon usage (RSCU) patterns with CoVs were commonly derived from the human chromosome 12, and mouse chromosome 6 and 12, suggesting that there might be a specific genomic region or chromosomes which show a more similar synonymous codon usage pattern with viral genes. Our findings contribute to developing the codon-optimization method in DNA vaccines, and further study is needed to determine a specific correlation between the codon usage patterns and the chromosomal locations in higher organisms.
Animals ; Codon/*genetics ; Humans ; Lectins, C-Type/*genetics ; Membrane Glycoproteins/*genetics ; Mice ; Nucleocapsid/*genetics ; Phylogeny ; SARS Virus/*genetics/pathogenicity ; Severe Acute Respiratory Syndrome/prevention & control ; Species Specificity ; Vaccines, DNA ; Viral Envelope Proteins/*genetics ; Virus Attachment

BACKGROUND: The purpose of this study was to explore the factors related to internet addiction in college students in Korea. METHODS: This study was a cross-sectional survey of college students in Seoul, and data was collected through self-report questionnaires. Data was analyzed by one-way analysis of variance, Fisher's exact test, Kruskal-Wallis rank test, and ordinary logistic regression analysis. RESULTS: In the ordinary logistic regression analysis, the factors related to a higher risk of internet addiction were lower frequency of exercise (P=0.017), lower level of self-control (P<0.001), higher level of stress (P<0.001), living with parents (P=0.011), using the internet for extended periods of time (P<0.001), and using the internet in their own rooms (P<0.001). CONCLUSIONS: Our results suggest that exercise, self-control, stress, living with parents, and duration and place of internet use are associated with internet addiction in college students. This information can be used to design methods for preventing internet addiction. More specific studies on internet addiction in college students are needed.
Behavior, Addictive ; Cross-Sectional Studies ; Humans ; Hypogonadism ; Internet ; Logistic Models ; Mitochondrial Diseases ; Ophthalmoplegia ; Parents ; Surveys and Questionnaires

To investigate the genomic properties of HIV-1, we collected 3,081 sequences from the HIV Sequence Database. The sequences were categorized according to sampling region, country, year, subtype, gene name, and sequence and were saved in a database constructed for this study. The relative synonymous codon usage (RSCU) values of matrix, capsid, and gp120 and gp41 genes were calculated using correspondence analysis. The synonymous codon usage patterns based on the geographical regions of African countries showed broad distributions; when all the other regions, including Asia, Europe, and the Americas, were taken into account, the Asian countries tended to be divided into two groups. The sequences were clustered into nine non-CRF subtypes. Among these, subtype C showed the most distinct codon usage pattern. To determine why the codon usage patterns in Asian countries were divided into two groups for four target genes, the sequences of the isolates from the Asian countries were analyzed. As a result, the synonymous codon usage patterns among Asian countries were divided into two groups, the southern Asian countries and the other Asian countries, with subtype 01_AE being the most dominant subtype in southern Asia. In summary, the synonymous codon usage patterns among the individual HIV-1 subtypes reflect genetic variations, and this bioinformatics technique may be useful in conjunction with phylogenetic methods for predicting the evolutionary patterns of pandemic viruses.
HIV-1/*genetics/*isolation & purification ; Gene Expression Regulation, Viral/*genetics ; Europe/epidemiology ; Codon/*genetics ; Asia/epidemiology ; Americas/epidemiology ; Africa/epidemiology

BACKGROUND: Metabolic syndrome is a major risk factor for cardiovascular disease. The combination of an aging population with a chronic diseased population is leading to an increase in the mortality rate due to cardiovascular diseases. The purpose of this study was to assess the prevalence of metabolic syndrome in the Korean population and to evaluate its related factors for sex differences. METHODS: From April 2007 to December 2008, a total of 2,729 volunteers aged 40-69 years living in Changwon city underwent a clinical examination at a hospital in Changwon, Korea. Metabolic syndrome was diagnosed following the criteria defined in Circulation 2009. The clinical examination included measuring anthropometric variables and cardiovascular risk factors, while lifestyle factors were assessed through a questionnaire. RESULTS: The prevalence of metabolic syndrome in our sampling pool was 25.2% with a break down by sex showing a rate of 30.2% in men and 22.2% in women. Related factors associated with metabolic syndrome common to both sex were age, self-health assessment, and alcohol consumption. Sleep duration seemed to be a related factor in men, while income, education, and menstruation status played significant roles in women. CONCLUSIONS: To better manage metabolic syndrome, men need to be educated on alcohol use and women of low socioeconomic status require particular attention as do the aging population and postmenopausal women.
Adult ; Aged ; Aging ; Alcohol Drinking ; Cardiovascular Diseases ; Female ; Humans ; Korea ; Life Style ; Male ; Menstruation ; Prevalence ; Risk Factors ; Sex Characteristics ; Social Class

We compared genetic variations in the VP1 gene of foot-and-mouth disease viruses (FMDVs) isolated since 2000 from various region of the world. We analyzed relative synonymous codon usage (RSCU) and phylogenetic relationship between geographical regions, and calculated the genetic substitution patterns between Korean isolate and those from other countries. We calculated the ratios of synonymously substituted codons (SSC) to all observed substitutions and developed a new analytical parameter, EMC (the ratio of exact matching codons within each synonymous substitution group) to investigate more detailed substitution patterns within each synonymous codon group. We observed that FMDVs showed distinct RSCU patterns according to phylogenetic relationships in the same serotype (serotype O). Moreover, while the SSC and EMC values of FMDVs decreased according to phylogenetic distance, G + C composition at the third codon position was strictly conserved. Although there was little variation among the SSC values of 18 amino acids, more dynamic differences were observed in EMC values. The EMC values of 4- and 6-fold degenerate amino acids showed significantly lower values while most 2-fold degenerate amino acids showed no significant difference. Our findings suggest that different EMC patterns among the 18 amino acids might be an important factor in determining the direction of evolution in FMDV.
Animals ; Capsid Proteins/*genetics ; Cattle ; Codon/*genetics ; Evolution, Molecular ; Foot-and-Mouth Disease/diagnosis/epidemiology/*virology ; Foot-and-Mouth Disease Virus/*genetics/isolation & purification ; Gene Frequency ; Geography ; Korea ; Phylogeography ; Polymorphism, Genetic ; RNA, Viral/*analysis ; Species Specificity

We compared genetic variations in the VP1 gene of foot-and-mouth disease viruses (FMDVs) isolated since 2000 from various region of the world. We analyzed relative synonymous codon usage (RSCU) and phylogenetic relationship between geographical regions, and calculated the genetic substitution patterns between Korean isolate and those from other countries. We calculated the ratios of synonymously substituted codons (SSC) to all observed substitutions and developed a new analytical parameter, EMC (the ratio of exact matching codons within each synonymous substitution group) to investigate more detailed substitution patterns within each synonymous codon group. We observed that FMDVs showed distinct RSCU patterns according to phylogenetic relationships in the same serotype (serotype O). Moreover, while the SSC and EMC values of FMDVs decreased according to phylogenetic distance, G + C composition at the third codon position was strictly conserved. Although there was little variation among the SSC values of 18 amino acids, more dynamic differences were observed in EMC values. The EMC values of 4- and 6-fold degenerate amino acids showed significantly lower values while most 2-fold degenerate amino acids showed no significant difference. Our findings suggest that different EMC patterns among the 18 amino acids might be an important factor in determining the direction of evolution in FMDV.
Animals ; Capsid Proteins/*genetics ; Cattle ; Codon/*genetics ; Evolution, Molecular ; Foot-and-Mouth Disease/diagnosis/epidemiology/*virology ; Foot-and-Mouth Disease Virus/*genetics/isolation & purification ; Gene Frequency ; Geography ; Korea ; Phylogeography ; Polymorphism, Genetic ; RNA, Viral/*analysis ; Species Specificity

Prion proteins (PrPs) are infectious pathogens that cause a group of invariably fatal, neurodegenerative diseases, including Creutzfeldt-Jakob disease, by means of an entirely novel mechanism. They are produced by various species, including reptile, rodent, ruminant and mammals, during normal metabolic processes, but they can be slowly changed into pathogenic isoforms upon contact with other infectious PrP isoforms. This transmission can occur across species barriers. In the present study, phylogram for each PrP sequence was generated by PAUP* 4.0 program using Neighbor-Joining method with 1,000 times bootstrapping process for the phylogenetic analysis. The molecular dynamics (MD) simulations were performed by the SANDER module in the AMBER 7 package using Amber 99 force field. All the simulation process was conducted in the IBM p690 Supercomputing System in Korea Institute of Science and Technology Information. To reduce the calculation time, we used the Generalized Born (GB) model. We compared the sequences and structural characteristics of normal and pathogenic (E200K) human PrPs with those of other reptile, rodent, ruminant and mammalian PrPs. Phylogenetic analysis revealed that, although the turtle PrP sequence is the most distinct of the PrPs analyzed, it nonetheless retains five conserved secondary structural elements that are similar to those found in the mammalian PrPs, suggesting that these elements have important functions in vivo. The RMS deviation between the normal and E200K human PrPs was larger than that between the normal human and bovine PrPs, and all of the beta-sheet structures in human E200K PrP were very stable during MD simulations.
Animals ; Cattle ; *Computational Biology ; Humans ; Phylogeny ; Prions/*chemistry/classification/*genetics/isolation & purification ; Reptiles/metabolism ; Rodentia/metabolism ; Ruminants/metabolism ; Sequence Analysis, Protein ; Species Specificity

A previous animal study has shown the effects of erythropoietin (EPO) and its non-erythropoietic carbamylated derivative (CEPO) on neurogenesis in the dentate gyrus. In the present study, we sought to investigate the effect of EPO on adult hippocampal neurogenesis, and to compare the ability of EPO and CEPO promoting dendrite elongation in cultured hippocampal neural progenitor cells. Two-month-old male BALB/c mice were given daily injections of EPO (5 U/g) for seven days and were sacrificed 12 hours after the final injection. Proliferation assays demonstrated that EPO treatment increased the density of bromodeoxyuridine (BrdU)-labeled cells in the subgranular zone (SGZ) compared to that in vehicle-treated controls. Functional differentiation studies using dissociated hippocampal cultures revealed that EPO treatment also increased the number of double-labeled BrdU/microtubule-associated protein 2 (MAP2) neurons compared to those in vehicle-treated controls. Both EPO and CEPO treatment significantly increased the length of neurites and spine density in MAP2(+) cells. In summary, these results provide evidences that EPO and CEPO promote adult hippocampal neurogenesis and neuronal differentiation. These suggest that EPO and CEPO could be a good candidate for treating neuropsychiatric disorders such as depression and anxiety associated with neuronal atrophy and reduced hippocampal neurogenesis.
Adult ; Animals ; Anxiety ; Atrophy ; Bromodeoxyuridine ; Dendrites ; Dentate Gyrus ; Depression ; Erythropoietin ; Hippocampus ; Humans ; Male ; Mice ; Neurites ; Neurogenesis ; Neurons ; Spine ; Stem Cells

The purpose of this study was to investigate the influence of various occlusal loading sites and directions on the stress distribution of the cervical composite resin restorations of maxillary second premolar, using 3 dimensional (3D) finite element (FE) analysis. Extracted maxillary second premolar was scanned serially with Micro-CT (SkyScan1072; SkyScan, Aartselaar, Belgium). The 3D images were processed by 3D-DOCTOR (Able Software Co., Lexington, MA, USA). HyperMesh (Altair Engineering, Inc., Troy, USA) and ANSYS (Swanson Analysis Systems, Inc., Houston, USA) was used to mesh and analyze 3D FE model. Notch shaped cavity was filled with hybrid (Z100, 3M Dental Products, St. Paul, MN, USA) or flowable resin (Tetric Flow, Vivadent Ets., FL-9494-Schaan, Liechtenstein) and each restoration was simulated with adhesive layer thickness (40 microm). A static load of 200 N was applied on the three points of the buccal incline of the palatal cusp and oriented in 20degrees increments, from vertical (long axis of the tooth) to oblique 40degrees direction towards the buccal. The maximum principal stresses in the occlusal and cervical cavosurface margin and vertical section of buccal surfaces of notch-shaped class V cavity were analyzed using ANSYS. As the angle of loading direction increased, tensile stress increased. Loading site had little effect on it. Under same loading condition, Tetric Flow showed relatively lower stress than Z100 overall, except both point angles. Loading direction and the elastic modulus of restorative material seem to be important factor on the cervical restoration.
Acrylic Resins ; Adhesives ; Axis, Cervical Vertebra ; Bicuspid ; Chimera ; Composite Resins ; Elastic Modulus ; Finite Element Analysis ; Polyurethanes