Ultralow-dielectric-constant amorphous boron nitride.

Decrease in processing speed due to increased resistance and capacitance delay is a major obstacle for the down-scaling of electronics1-3. Minimizing the dimensions of interconnects (metal wires that connect different electronic components on a chip) is crucial for the miniaturization of devices. Interconnects are isolated from each other by non-conducting (dielectric) layers. So far, research has mostly focused on decreasing the resistance of scaled interconnects because integration of dielectrics using low-temperature deposition processes compatible with complementary metal-oxide-semiconductors is technically challenging. Interconnect isolation materials must have low relative dielectric constants (κ values), serve as diffusion barriers against the migration of metal into semiconductors, and be thermally, chemically and mechanically stable. Specifically, the International Roadmap for Devices and Systems recommends4 the development of dielectrics with κ values of less than 2 by 2028. Existing low-κ materials (such as silicon oxide derivatives, organic compounds and aerogels) have κ values greater than 2 and poor thermo-mechanical properties5. Here we report three-nanometre-thick amorphous boron nitride films with ultralow κ values of 1.78 and 1.16 (close to that of air, κ = 1) at operation frequencies of 100 kilohertz and 1 megahertz, respectively. The films are mechanically and electrically robust, with a breakdown strength of 7.3 megavolts per centimetre, which exceeds requirements. Cross-sectional imaging reveals that amorphous boron nitride prevents the diffusion of cobalt atoms into silicon under very harsh conditions, in contrast to reference barriers. Our results demonstrate that amorphous boron nitride has excellent low-κ dielectric characteristics for high-performance electronics.

Wafer-Scale Programmed Assembly of One-Atom-Thick Crystals.

Crystalline films offer various physical properties based on the modulation of their thicknesses and atomic structures. The layer-by-layer assembly of atomically thin crystals provides a powerful means to arbitrarily design films at the atomic level, which are unattainable with existing growth technologies. However, atomically clean assembly of the materials with high scalability and reproducibility remains challenging. We report programmed crystal assembly of graphene and monolayer hexagonal boron nitride, assisted by van der Waals interactions, to form wafer-scale films of pristine interfaces with near-unity yield. The atomic configurations of the films are tailored with layer-resolved compositions and in-plane crystalline orientations. We demonstrate batch-fabricated tunnel device arrays with modulation of the resistance over orders of magnitude by thickness control of the hexagonal boron nitride barrier with single-atom precision and large-scale, twisted multilayer graphene with programmable electronic band structures and crystal symmetries. Our results constitute an important development in the artificial design of large-scale films.

Muricauda lutisoli sp. nov., isolated from mudflat.

A Gram-negative, nonmotile, rod-shaped bacterium, designated strain CAU 1631T, was isolated from a mudflat sample in the Republic of Korea. Strain CAU 1631T grew optimally at 30 °C, pH 6.5, and 1% (w/v) NaCl solution. Phylogenetic analysis based on 16S rRNA gene sequencing and 92 core genes indicated that strain CAU 1631T is a member of the genus Muricauda and most closely related to Muricauda oceanensis 40DY170T and Muricauda lutimaris SMK-108T (98.1%, both). The draft genome was 3.4 Mb with 3064 protein-coding genes, and the DNA G + C content was 43.3 mol%. The major fatty acids were iso-C15:0, iso-C17:0 3-OH, and iso-C15:0 G, and the major polar lipid was phosphatidylethanolamine. The predominant respiratory quinone was MK-6. Based on the comprehensive taxonomic characterization, strain CAU 1631T is a novel species, for which the name Muricauda lutisoli sp. nov. has been proposed. The type strain is CAU 1631T (= KCTC 82456T = MCCC 1K06088T).

Halomarinibacterium sedimenti gen. nov., sp. nov., a carotenoid pigment-producing bacterium isolated from marine sediment.

A Gram-negative, strictly aerobic, non-motile, rod-shaped bacterial strain CAU 1614T was isolated from a marine sediment sample collected in the Republic of Korea. Optimal growth of strain CAU 1614T proceeded at 30 °C, pH 7.0, and 2% (w/v) NaCl. 16S rRNA gene similarity was lower than 94.5% with genera Aureisphaera, Marinirhabdus, Aureitalea, Gilvibacter, Ulvibacter, and Jejudonia. The highest similarity was with Aureisphaera galaxeae 04OKA003-7T (94.5%). The major cellular fatty acids were iso-C15:0, iso-C16:0, iso-C15:1 G, iso-C16:0 3-OH, and iso-C17:0 3-OH and the predominant menaquinone was MK-6. The polar lipids were phosphatidylethanolamine, phosphoglycolipid, an unidentified lipid, two unidentified aminolipids, and an unidentified glycolipid. The draft genome of strain CAU 1614T was 3.9 Mb and DNA G+C content was 36.0 mol%. On the basis of the phenotypic, chemotaxonomic, and genomic data, strain CAU 1614T presents a novel genus in the family Flavobacteriaceae, for which the name Halomarinibacterium sedimenti gen. nov., sp. nov. is proposed. The type strain is CAU 1614T (= KCTC 82457T = MCCC 1K06083T).

Efficacy of intraoperative bulbocavernosus reflex monitoring for the prediction of postoperative voiding function in adult patients with lumbosacral spinal tumor.

Lumbosacral spinal tumor surgery is associated with a relatively high risk of postoperative voiding dysfunction. This study aimed to investigate the correlation between intraoperative bulbocavernosus reflex (BCR) changes and postoperative voiding function in adult patients with lumbosacral spinal tumors. We retrospectively reviewed 63 patients who underwent intradural conus and cauda equina tumor surgeries with intraoperative BCR monitoring. We evaluated patients' voiding functions for 6 months postoperatively. BCR was maintained in 60 patients and disappeared in 3 patients at the end of the surgery. Among the patients in whom BCR was maintained, examinations conducted at discharge and at 1- and 6-month follow-ups revealed that 7 (11.7%), 4 (6.7%), and zero (0.0%) patients experienced voiding difficulty, respectively. However, all 3 (100%) patients without BCR experienced voiding difficulty at the three corresponding follow-ups. Data analysis indicated no significant difference in voiding between the maintained and disappeared BCR groups 6-months postoperatively. The sensitivity, specificity, positive predictive, and negative predictive values of intraoperative BCR monitoring for detecting new and worsening difficulty in voiding were all 100% 6 months postoperatively. Our results shows that intraoperative BCR monitoring is a reliable predictor of voiding function following surgery in adult patients undergoing lumbosacral spinal tumor surgery. Intraoperative BCR monitoring can be useful for assessing and monitoring the integrity of the voiding function during lumbosacral spinal tumor surgery.

Oxygen-Vacancy-Driven Orbital Reconstruction at the Surface of TiO2 Core-Shell Nanostructures.

Oxygen vacancies and their correlation with the electronic structure are crucial to understanding the functionality of TiO2 nanocrystals in material design applications. Here, we report spectroscopic investigations of the electronic structure of anatase TiO2 nanocrystals by employing hard and soft X-ray absorption spectroscopy measurements along with the corresponding model calculations. We show that the oxygen vacancies significantly transform the Ti local symmetry by modulating the covalency of titanium-oxygen bonds. Our results suggest that the altered Ti local symmetry is similar to the C3v, which implies that the Ti exists in two local symmetries (D2d and C3v) at the surface. The findings also indicate that the Ti distortion is a short-range order effect and presumably confined up to the second nearest neighbors. Such distortions modulate the electronic structure and provide a promising approach to structural design of the TiO2 nanocrystals.

Reaction Behaviors of S-, O-, and N-containing Aliphatic Molecules with a Propyl Moiety on Ge(100) Surface.

The reaction pathways of 1-propanethiol, 1-propanol, and propylamine molecules, containing a propyl moiety, on a Ge(100) surface were investigated using high-resolution photoemission spectroscopy (HRPES) experiments and density functional theory (DFT) calculations. Upon analysis of the HRPES data, the adsorption of 1-propanethiol and 1-propanol was found to occur through a dissociation reaction, whereas that of propylamine took place via N dative bonding at room temperature. On the basis of our DFT results, adsorption geometries and transition states for each of these molecules on the Ge(100) surface were confirmed. Systematic studies of S-, O-, and N-containing molecules, composed of an identical propyl moiety, on the Ge(100) surface provide insight into the adsorption mechanism of aliphatic molecules containing alkyl chains on the Ge(100) surface.

Correlation between structural phase transition and surface chemical properties of thin film SrRuO3/SrTiO3 (001).

The correlation between the structural phase transition (SPT) and oxygen vacancy in SrRuO3 (SRO) thin films was investigated by in situ X-ray diffraction (XRD) and ambient pressure X-ray photoelectron spectroscopy (AP-XPS). In situ XRD shows that the SPT occurs from a monoclinic SRO phase to a tetragonal SRO phase near ∼200 °C, regardless of the pressure environment. On the other hand, significant core level shifts in both the Ru and Sr photoemission spectra are found under ultrahigh vacuum, but not under the oxygen pressure environment. The directions and behavior of the core level shift of Ru and Sr are attributed to the formation of oxygen vacancy across the SPT temperature of SRO. The analysis of in situ XRD and AP-XPS results provides an evidence for the formation of metastable surface oxide possibly due to the migration of internal oxygen atoms across the SPT temperature, indicating the close relationship between oxygen vacancy and SPT in SRO thin films.

All-Dry Transfer of Graphene Film by van der Waals Interactions.

We report a method that uses van der Waals interactions to transfer continuous, high-quality graphene films from Ge(110) to a different substrate held by hexagonal boron nitride carriers in a clean, dry environment. The transferred films are uniform and continuous with low defect density and few charge puddles. The transfer is effective because of the weak interfacial adhesion energy between graphene and Ge. Based on the minimum strain energy required for the isolation of film, the upper limit of the interfacial adhesion energy is estimated to be 23 meV per carbon atom, which makes graphene/Ge(110) the first as-grown graphene film that has a substrate adhesion energy lower than that of typical van der Waals interactions between layered materials. Our results suggest that graphene on Ge can serve as an ideal material platform to be integrated with other material systems by a clean assembly process.

The immunotherapeutic effects of recombinant Bacillus Calmette-Guérin resistant to antimicrobial peptides on bladder cancer cells.

PURPOSE: Although Mycobacterium bovis Bacillus Calmette-Guérin (BCG) is the most widely used bladder cancer immunotherapy, innate immune responses involving antimicrobial peptides (AMPs) cause BCG failure and unwanted side effects. Here, we generated genetically modified BCG strains with improved immunotherapeutic effects by adding genes that confer evasion of AMPs. MATERIALS AND METHODS: We constructed recombinant BCG (rBCG) strains expressing Streptococcal inhibitor of complement (Sic), which confers resistance to human α-defensin-1 and cathelicidin, and d-alanyl carrier protein ligase (dltA), which confers resistance to cationic AMPs. Sic and dltA were separately cloned into the pMV306 plasmid and introduced into BCG via electroporation. Then, the efficacy of the rBCGs was tested in a growth inhibition assay using two bladder cancer cell lines (5637, T24). RESULTS: We confirmed the presence of cDNA segments corresponding to the Sic and dltA genes in total mRNA of the rBCG strains containing Sic (rBCG-Sic) and dltA (rBCG-dltA), and these rBCGs showed higher survival against AMPs. The growth inhibitory effects of rBCGs on bladder cancer cells were significantly enhanced compared to those of the parent BCG, and THP-1 migration also increased. After 8 h of infection, the levels of internalization were higher in rBCG-infected bladder cancer cells than in BCG-infected cells, and cells infected with rBCGs showed increased release of antitumor cytokines, such as IL-6/12, TNF-α, and INF-γ, resulting in inhibition of bacterial killing and immune modulation via antimicrobial peptides. CONCLUSIONS: rBCG-Sic and rBCG-dltA can effectively evade BCG-stimulated AMPs, and may be significantly improved immunotherapeutic tools to treat bladder cancer.

Kyphectomy and interbody fixation using lag screws in a child with myelomeningocele kyphosis: a technical case report.

A 5-year-old boy had a thoracolumbar-level MMC that had been repaired at the day after birth and kyphotic deformity got worse as he grew. He complained of discomfort about not being able to take a supine posture and decided to perform surgery for kyphosis. In our case, surgical correction is offered to stop the deformity progression, manage the associated pain, and finally to gain sitting and supine posture. We report the surgical procedure with 4 levels of en bloc kyphectomy and using the lag screws. Especially when lag screws are used, several complications including posterior instrumentation failure, hardware prominence and wound break down can be solved by removing the implants after bone fusion has been achieved.

DRG2 Deficient Mice Exhibit Impaired Motor Behaviors with Reduced Striatal Dopamine Release.

Developmentally regulated GTP-binding protein 2 (DRG2) was first identified in the central nervous system of mice. However, the physiological function of DRG2 in the brain remains largely unknown. Here, we demonstrated that knocking out DRG2 impairs the function of dopamine neurons in mice. DRG2 was strongly expressed in the neurons of the dopaminergic system such as those in the striatum (Str), ventral tegmental area (VTA), and substantia nigra (SN), and on neuronal cell bodies in high-density regions such as the hippocampus (HIP), cerebellum, and cerebral cortex in the mouse brain. DRG2 knockout (KO) mice displayed defects in motor function in motor coordination and rotarod tests and increased anxiety. However, unexpectedly, DRG2 depletion did not affect the dopamine (DA) neuron population in the SN, Str, or VTA region or dopamine synthesis in the Str region. We further demonstrated that dopamine release was significantly diminished in the Str region of DRG2 KO mice and that treatment of DRG2 KO mice with l-3,4-dihydroxyphenylalanine (L-DOPA), a dopamine precursor, rescued the behavioral motor deficiency in DRG2 KO mice as observed with the rotarod test. This is the first report to identify DRG2 as a key regulator of dopamine release from dopamine neurons in the mouse brain.

A cellular mechanism of muscle memory facilitates mitochondrial remodelling following resistance training.

KEY POINTS: Referring to the muscle memory theory, previously trained muscles acquire strength and volume much faster than naive muscles. Using extreme experimental models such as synergist ablation or steroid administration, previous studies have demonstrated that the number of nuclei increases when a muscle becomes enlarged, which serves as a cellular muscle memory mechanism for the muscle. In the present study, we found that, when rats were subjected to physiologically relevant resistance training, the number of myonuclei increased and was retained during a long-term detraining period. The acquired myonuclei were related to a greater degree of muscle hypertrophic and mitochondrial biogenesis processes following subsequent hypertrophic conditions. Our data suggest a cellular mechanism supporting the notion that exposing young muscles to resistance training would help to restore age-related muscle loss coupled with mitochondrial dysfunction in later life. ABSTRACT: Muscle hypertrophy induced by resistance training is accompanied by an increase in the number of myonuclei. The acquired myonuclei are viewed as a cellular component of muscle memory by which muscle enlargement is promoted during a re-training period. In the present study, we investigated the effect of exercise preconditioning on mitochondrial remodelling induced by resistance training. Sprague-Dawley rats were divided into four groups: untrained control, training, pre-training or re-training. The training groups were subjected to weight loaded-ladder climbing exercise training. Myonuclear numbers were significantly greater (up to 20%) in all trained muscles compared to untrained controls. Muscle mass was significantly higher in the re-training group compared to the training group (∼2-fold increase). Mitochondrial content, mitochondrial biogenesis gene expression levels and mitochondrial DNA copy numbers were significantly higher in re-trained muscles compared to the others. Oxidative myofibres (type I) were significantly increased only in the re-trained muscles. Furthermore, in vitro studies using insulin-like growth factor-1-treated L6 rat myotubes demonstrated that myotubes with a higher myonuclear number confer greater expression levels of both mitochondrial and nuclear genes encoding for constitutive and regulatory mitochondrial proteins, which also showed a greater mitochondrial respiratory function. These data suggest that myonuclei acquired from previous training facilitate mitochondrial biogenesis in response to subsequent retraining by (at least in part) enhancing cross-talk between mitochondria and myonuclei in the pre-conditioned myofibres.

S2 alar iliac screw placement under robotic guidance for adult spinal deformity patients: technical note.

PURPOSE: S2 alar-iliac (S2AI) screws are generally placed using an open approach, but have recently been shown to be implantable using a minimally invasive approach. Nevertheless, optimal screw positioning, even when supported by fluoroscopic guidance, is challenging in the complex anatomy of the sacral-pelvic area. This work presents our novel technique of S2AI sacropelvic fixation procedures performed with robotic guidance. METHODS: This was a single-center, retrospective, mini case-series of adult spinal deformity patients in need of sacropelvic fixation as part of a longer thoraco-lumbar fusion. The surgeon drilled a pilot hole through a robotic guide and then inserted a K-wire. A Jamshidi needle was placed over the K-wire and used to advance the pilot hole anterolaterally. RESULTS: Medical charts of four 60-70 year-old patients, who underwent robotic-guided insertion of S2AI screws in a minimally invasive approach were reviewed. Follow-up ranged between 10 and 13 months. Post-operative CTs and X-rays showed all eight trajectories were fully within the bone and accurately placed. Average surgery time per patient was 13 min with 5.3 s of fluoroscopy per screw. No intra- or post-operative complications occurred. CONCLUSIONS: Robotic-guidance with a Jamshidi needle technique was a safe and effective means for implanting S2AI screws in a minimally invasive approach.

Cervical compressive myelopathy: flow analysis of cerebrospinal fluid using phase-contrast magnetic resonance imaging.

PURPOSE: To evaluate cerebrospinal fluid (CSF) flow in cervical compressive myelopathy (CCM), by both quantitative and qualitative analyses, using 3T cine phase-contrast magnetic resonance imaging (cine MRI). METHODS: From September, 2014 to June, 2015, we enrolled 45 subjects (18 women and 27 men, mean age, 61.7 ± 13.4 years) to undergo cervical cine MRI. The subjects were divided into three groups: no stenosis and cervical stenosis with and without intramedullary T2 hyperintensity. We measured maximal CSF velocity, and 12 CSF velocity waveforms were plotted per subject. Two readers independently assessed the CSF waveform shape (0 absent; 1 serrated; 2 bi-directional with small amplitude; and 3 normal bi-directional waveform) and the CSF motion pattern (0 absent; 1 interrupted; and 2 intact). The numbers of 12 waveform shapes were summed to yield a CSF waveform score. Linear mixed model and ROC curve analyses were used for statistical analyses. RESULTS: Maximal CSF velocity was significantly lower in CCM (marginal mean, 2.72 cm/s) than in stenosis without intramedullary T2 hyperintensity (3.27 cm/s, p = 0.027) and no stenosis (3.80 cm/s, p < 0.001). Bi-phasic CSF motion was lost in cervical stenosis. CSF waveform scores of 17 (area under curve (AUC), 0.797; p = 0.003) and 16.5 (AUC, 0.790; p = 0.004) could predict Japanese Orthopedic Association (JOA) score corresponding to CCM. CONCLUSIONS: Maximal CSF velocity and CSF waveform score on cine MRI decreased in CCM and was correlated with the JOA score. Thus, both quantitative and qualitative analyses using cine MRI could effectively demonstrate CSF flow alterations in CCM.

Identification of Novel A2/C2 Inter-Genotype Recombinants of Hepatitis B Virus from a Korean Chronic Patient Co-Infected with Both Genotype A2 and C2.

Nearly all cases of Hepatitis B virus (HBV) infections in South Korea have the C2 genotype. Here, we have identified a chronically infected patient who was co-infected with HBV of both the A2 and C2 genotypes by screening 135 Korean chronically infected patients using direct sequencing protocols targeting the 1032-bp polymerase reverse transcriptase (RT) region. Further polymerase chain reaction (PCR)-cloning analysis (22 clones) of the RT showed that this patient had genotype C2 (12 clones), genotype A2 (six clones) and A2/C2 inter-genotype HBV recombinants (four clones). BootScan analysis showed that three of the four recombinants have different types of recombination breakpoints in both the RT and overlapping hepatitis B surface antigen (HBsAg) region. Given the significance of HBsAg as a diagnostic or vaccination target against HBV infection, clinical implications of these identified recombinants should be studied in the future. To our knowledge, this is the first report on A2/C2 inter-genotype HBV recombinants.

Long-term recurrence rates after the removal of spinal meningiomas in relation to Simpson grades.

PURPOSE: Simpson grade II removal (coagulation of the dural attachment after gross total removal) of spinal meningioma is considered an acceptable alternative, but increased recurrence after more than 10 years has been reported. More attention must be paid to the long-term surgical outcomes after Simpson grade II removal. METHODS: A retrospective review was performed for 20 patients (M:F = 5:15; age, 59 ± 9 years) with Simpson grade II removal (mean follow-up period, 12.9 years; range 10.0-17.5). Magnetic resonance (MR) imaging was conducted in 17 patients at 88 ± 52 months (range 12-157). During the same period, Simpson grade I removal (removal of the dural origin) was performed in 21 patients (follow-up, 89 ± 87 months; range 9-316). Radiological recurrence was defined as a visible tumor on a follow-up MR image, and clinical tumor recurrence was defined as the recurrence of symptoms. RESULTS: At the final follow-up, neurological symptoms had improved in 16/20 patients and remained stable in 4/20. A recurrent tumor was detected in one patient due to increased back pain at 92 months postoperative, but the symptom was stable without surgery until the last follow-up (124 months). The radiological and clinical recurrence-free survival periods were 150 ± 7 months (95 % CI 136-163) and 204 ± 6 months (95 % CI 193-215), respectively. There was no recurrence after Simpson grade I removal, whereas neurological deterioration occurred in two patients after surgery. CONCLUSIONS: Simpson grade II removal may be an alternative option if the risk of complications with Simpson grade I removal is expected to be high.

Dynamic stabilization using the Dynesys system versus posterior lumbar interbody fusion for the treatment of degenerative lumbar spinal disease: a clinical and radiological outcomes-based meta-analysis.

OBJECTIVE The Dynesys, a pedicle-based dynamic stabilization (PDS) system, was introduced to overcome the drawbacks of fusion procedures. Nevertheless, the theoretical advantages of PDS over fusion have not been clearly confirmed. The aim of this study was to compare clinical and radiological outcomes of patients who underwent PDS using the Dynesys system with those who underwent posterior lumbar interbody fusion (PLIF). METHODS The authors searched PubMed, Embase, Web of Science, and the Cochrane Database. Studies that reported outcomes of patients who underwent PDS or PLIF for the treatment of degenerative lumbar spinal disease were included. The primary efficacy end points were perioperative outcomes. The secondary efficacy end points were changes in the Oswestry Disability Index (ODI) and back and leg pain visual analog scale (VAS) scores and in range of motion (ROM) at the treated and adjacent segments. A meta-analysis was performed to calculate weighted mean differences (WMDs), 95% confidence intervals, Q statistics, and I(2) values. Forest plots were constructed for each analysis group. RESULTS Of the 274 retrieved articles, 7 (which involved 506 participants [Dynesys, 250; PLIF, 256]) met the inclusion criteria. The Dynesys group showed a competitive advantage in mean surgery duration (20.73 minutes, 95% CI 8.76-32.70 minutes), blood loss (81.87 ml, 95% CI 45.11-118.63 ml), and length of hospital stay (1.32 days, 95% CI 0.23-2.41 days). Both the Dynesys and PLIF groups experienced improved ODI and VAS scores after 2 years of follow-up. Regarding the ODI and VAS scores, no statistically significant difference was noted according to surgical procedure (ODI: WMD 0.12, 95% CI -3.48 to 3.72; back pain VAS score: WMD -0.15; 95% CI -0.56 to 0.26; leg pain VAS score: WMD -0.07; 95% CI -0.47 to 0.32). The mean ROM at the adjacent segment increased in both groups, and there was no substantial difference between them (WMD 1.13; 95% CI -0.33 to 2.59). Although the United States is the biggest market for Dynesys, no eligible study from the United States was found, and 4 of 8 enrolled studies were performed in China. The results must be interpreted with caution because of publication bias. During Dynesys implantation, surgeons have to decide the length of the spacer and cord pretension. These values are debatable and can vary according to the surgeon's experience and the patient's condition. Differences between the surgical procedures were not considered in this study. CONCLUSIONS Fusion still remains the method of choice for advanced degeneration and gross instability. However, spinal degenerative disease with or without Grade I spondylolisthesis, particularly in patients who require a quicker recovery, will likely constitute the main indication for PDS using the Dynesys system.

Regional Differences in Fall-Related Physical Fitness of the Elderly between Seoul, Korea and Gifu, Japan.

Falling is a leading cause of severe injuries among the elderly, such as hip fracture. This study examined the regional and sex differences in fall-related physical fitness of the elderly between Seoul, Korea and Gifu, Japan. The study included 87 elderly residents of Seoul (mean age 75.4 years; 21 males and 66 females) and 91 elderly residents of Gifu (mean age 71.9 years; 17 males and 74 females). The participants underwent various physical tests, and two-way ANCOVA (region × sex) with age as a covariate was used for statistical analysis. Significant interaction was shown by the one-legged stance (OLS) with eyes open test, which was higher in elderly females from Gifu than in those from Seoul. Significant main effects for the region were shown by the 30-s chair stand (CS-30) and reaction time tests, wherein the Gifu group performed better than the Seoul group. Significant main effects for sex were shown by the sit and reach, handgrip strength, and knee extension strength tests, which were higher for females in the sit and reach test and lower for females in the handgrip and knee extension strength tests compared to the corresponding males in both the cases. Lastly, elderly from Gifu performed better than those from Seoul in the reaction time, CS-30, and OLS tests. Since the ability to move quickly and maintain balance to avoid falling are factors necessary for reducing fall risk, fall prevention classes and exercise programs are required to improve these abilities in the elderly.

Identification of ISMyo2, a novel insertion sequence element of IS21 family and its diagnostic potential for detection of Mycobacterium yongonense.

BACKGROUND: Mycobacterium yongonense, as a novel member of the M. avium complex (MAC), was recently reported to be isolated from human specimens in South Korea and Italy. Due to its close relatedness to other MAC members, particularly M. intracellulare in taxonomic aspects, the development of a novel diagnostic method for its specific detection is necessary for clinical or epidemiologic purposes. METHODS: Using the Mycobacterium yongonense genome information, we have identified a novel IS-element, ISMyo2. Targeting the ISMyo2 sequence, we developed a real-time PCR method and applied the technique to Mycobacterial genomic DNA. RESULTS: To identify proper nucleic acid targets for the diagnosis, comparisons of all insertion sequence (IS) elements of 3 M. intracellulare and 3 M. yongonense strains, whose complete genome sequences we reported recently, led to the selection of a novel target gene, the M. yongonense-specific IS element, ISMyo2 (2,387 bp), belonging to the IS21 family. Next, we developed a real-time PCR method using SYBR green I for M. yongonense-specific detection targeting ISMyo2, producing a 338-bp amplicon. When this assay was applied to 28 Mycobacterium reference strains and 63 MAC clinical isolates, it produced amplicons in only the 6 M. yongonense strains, showing a sensitivity of 100 fg of genomic DNA, suggesting its feasibility as a diagnostic method for M. yongonense strains. CONCLUSIONS: We identified a novel ISMyo2 IS element belonging to the IS21 family specific to M. yongonense strains via genome analysis, and a real-time PCR method based on its sequences was developed.