PIN1 Suppresses the Hepatic Differentiation of Pulp Stem Cells via Wnt3a

This study aimed to investigate the role of PIN1 on the hepatic differentiation of human dental pulp stem cells (hDPSCs) and its signaling pathway, as well as the potential therapeutic effects of hDPSC transplantation and PIN1 inhibition on CCl₄ (carbon tetrachloride)-induced liver fibrosis in mice. The in vitro results showed that hepatic differentiation was suppressed by infection with adenovirus-PIN1 and promoted by PIN1 inhibitor juglone via the downregulation of Wnt3a and β-catenin. Compared with treatment with either hDPSC transplantation or juglone alone, the combination of hDPSCs and juglone into CCl₄-injured mice significantly suppressed liver fibrosis and restored serum levels of alanine transaminase, aspartate transaminase, and ammonia. Collectively, the present study shows for the first time that PIN1 inhibition promotes hepatic differentiation of hDPSCs through the Wnt/β-catenin pathway. Furthermore, juglone in combination with hDPSC transplantation effectively treats liver fibrosis, suggesting that hDPSC transplantation with PIN1 inhibition may be a novel therapeutic candidate for the treatment of liver injury.

Osteosarcoma in Pre-adolescent Patients

The medical records of 38 pre-adolescent (aged ≤ 10 years) and 43 adolescent (aged 11-15 years) patients with primary osteosarcoma treated using the same protocol were reviewed in order to determine whether the clinical features and prognosis differed between these two groups. Gender, tumour location, tumour size, serum levels of alkaline phosphatase and lactic dehydrogenase before treatment, and chemotherapy-induced tumour necrosis were recorded, together with survival data. These parameters were compared in the two groups, and their prognostic significance was evaluated in the pre-adolescent patients. There were no statistically significant differences in the clinical parameters between pre-adolescent and adolescent patients. Only a poor level of chemotherapy-induced tumour necrosis was significantly associated with a poor prognosis in pre-adolescent patients. This study indicates that osteosarcoma behaviour is similar in pre-adolescent and adolescent patients, and there appears to be little justification for adopting different therapies in these two groups.

Do family meals affect childhood overweight or obesity?: nationwide survey 2008-2012

BACKGROUND

The prevalence of childhood obesity is increasing worldwide and this trend is no exception for South Korea. A multidisciplinary approach is needed for the prevention and management of childhood obesity. To do so, among many other strategies, managing the family unit can be a very effective strategy.

OBJECTIVES

The purpose of this study was to identify the relationship between frequency of family meals and overweight/obesity in elementary students and to suggest the management and prevention strategies of childhood obesity.

METHODS

Data from a total of 2904 elementary students were analyzed from the 2008-2012 Korea National Health and Nutrition Examination Survey. Multiple logistic regression analysis was used to examine the association between overweight/obesity and family meals.

RESULTS

Of the total 2904 elementary students, 573 (19.4%) were overweight or obese. The odds ratio of overweight or obese students who had family dinner only was 1.21 (95% CI: 0.89-1.64), that of those who had family breakfast only was 3.20 (95% CI: 1.70-6.02), and that of those who had neither family breakfast nor family dinner was 4.17 (95% CI: 1.98-8.78) compared with those who had both family breakfast and family dinner.

CONCLUSIONS

The frequency of family meals was strongly an inverse association with childhood overweight or obesity. Therefore, we suggest that the intervention of childhood obesity should include family meals.

Reliability of classification of ring and little finger carpometacarpal joint fracture subluxations: a comparison between two-dimensional computed tomography and three-dimensional computed tomography classifications

The aims of this study were to develop a classification for ring and little finger carpometacarpal joint fracture subluxations based on three-dimensional computed tomography images and evaluate the inter- and intraobserver reliability of the three-dimensional computed tomography classification. A retrospective review was performed of 30 cases of ring and little finger carpometacarpal joint fracture subluxations from 2005 to 2013. We classified ring and little finger carpometacarpal joint fracture subluxations into three types based on three-dimensional computed tomography images. An orthopaedic surgeon with 2 years of experience, a consultant hand surgeon with 8 years of experience, and a consultant radiologist with 9 years of experience, who were completely blind to the treatment algorithm, evaluated 30 cases twice at a 2-week interval using our new classification based on three-dimensional computed tomography images and the other classification based on two-dimensional computed tomography images. Our three-dimensional computed tomography classification showed almost perfect interobserver and intraobserver reliability and resulted in a better level of agreement than two-dimensional computed tomography classification.

Biaxial Dielectrophoresis Force Spectroscopy: A Stoichiometric Approach for Examining Intermolecular Weak Binding Interactions

The direct quantification of weak intermolecular binding interactions is very important for many applications in biology and medicine. Techniques that can be used to investigate such interactions under a controlled environment, while varying different parameters such as loading rate, pulling direction, rupture event measurements, and the use of different functionalized probes, are still lacking. Herein, we demonstrate a biaxial dielectrophoresis force spectroscopy (BDFS) method that can be used to investigate weak unbinding events in a high-throughput manner under controlled environments and by varying the pulling direction (i.e., transverse and/or vertical axes) as well as the loading rate. With the BDFS system, we can quantitatively analyze binding interactions related to hydrogen bonding or ionic attractions between functionalized microbeads and a surface within a microfluidic device. Our BDFS system allowed for the characterization of the number of bonds involved in an interaction, bond affinity, kinetic rates, and energy barrier heights and widths from different regimes of the energy landscape.

Schwann cells induce cancer cell dispersion and invasion

Nerves enable cancer progression, as cancers have been shown to extend along nerves through the process of perineural invasion, which carries a poor prognosis. Furthermore, the innervation of some cancers promotes growth and metastases. It remains unclear, however, how nerves mechanistically contribute to cancer progression. Here, we demonstrated that Schwann cells promote cancer invasion through direct cancer cell contact. Histological evaluation of murine and human cancer specimens with perineural invasion uncovered a subpopulation of Schwann cells that associates with cancer cells. Coculture of cancer cells with dorsal root ganglion extracts revealed that Schwann cells direct cancer cells to migrate toward nerves and promote invasion in a contact-dependent manner. Upon contact, Schwann cells induced the formation of cancer cell protrusions in their direction and intercalated between the cancer cells, leading to cancer cell dispersion. The formation of these processes was dependent on Schwann cell expression of neural cell adhesion molecule 1 (NCAM1) and ultimately promoted perineural invasion. Moreover, NCAM1-deficient mice showed decreased neural invasion and less paralysis. Such Schwann cell behavior reflects normal Schwann cell programs that are typically activated in nerve repair but are instead exploited by cancer cells to promote perineural invasion and cancer progression.

Association between interleukin-27 polymorphisms and pulmonary tuberculosis

OBJECTIVE

To investigate the effect of interleukin (IL) 27 -964A/G, 2095T/G, 4603G/A and 4730T/C gene polymorphisms on the development of pulmonary tuberculosis (PTB), radiographic characteristics and severity.

DESIGN

Differences in the allele and genotype distributions of the -964A/G, 2095T/G, 4603G/A and 4730T/C polymorphisms between 224 PTB patients and 233 healthy controls, between patients with single- and multi-lobe involvement, and between patients with and without cavitation, were investigated. Serum IL-27 concentration was measured using an enzyme-linked immunosorbent assay.

RESULTS

There were no significant differences in the allele or genotype distributions between PTB patients and healthy controls. However, the -964A/A genotype was more prevalent in patients with single-lobe involvement than the -964A/G or -964G/G genotype in patients with multi-lobe involvement (50.0% vs. 31.3%, P = 0.01). There was no difference between patients with and without cavitation (P > 0.05). Serum median IL-27 concentration was significantly higher in patients with single-lobe involvement than in those with multi-lobe involvement (P = 0.03) and in those with -964A/A genotypes than in those with -964A/G or -964G/G genotypes (P = 0.02).

CONCLUSIONS

In terms of serum IL-27 levels, the -964 A/A genotype may be associated with a protective role that prevents the intrapulmonary spread of PTB rather than its development.

Identification of germline alterations in breast cancer predisposition genes among Malaysian breast cancer patients using panel testing

Although an association between protein-truncating variants and breast cancer risk has been established for 11 genes, only alterations in BRCA1, BRCA2, TP53 and PALB2 have been reported in Asian populations. Given that the age of onset of breast cancer is lower in Asians, it is estimated that inherited predisposition to breast cancer may be more significant. To determine the potential utility of panel testing, we investigated the prevalence of germline alterations in 11 established and 4 likely breast cancer genes in a cross-sectional hospital-based cohort of 108 moderate to high-risk breast cancer patients using targeted next generation sequencing. Twenty patients (19%) were identified to carry deleterious mutations, of whom 13 (12%) were in the BRCA1 or BRCA2, 6 (6%) were in five other known breast cancer predisposition genes and 1 patient had a mutation in both BRCA2 and BARD1. Our study shows that BRCA1 and BRCA2 account for the majority of genetic predisposition to breast cancer in our cohort of Asian women. Although mutations in other known breast cancer genes are found, the functional significance and breast cancer risk have not yet been determined, thus limiting the clinical utility of panel testing in Asian populations.

Characterization of the Stiffness of Multiple Particles Trapped by Dielectrophoretic Tweezers in a Microfluidic Device

Characterization of the stiffness of multiple particles trapped by tweezers-based force spectroscopy is a key step in building simple, high-throughput, and robust systems that can investigate the molecular interactions in a biological process, but the technology to characterize it in a given environment simultaneously is still lacking. We first characterized the stiffness of multiple particles trapped by dielectrophoretic (DEP) tweezers inside a microfluidic device. In this characterization, we developed a method to measure the thermal fluctuations of the trapped multiple particles with DEP tweezers by varying the heights of the particles in the given environment at the same time. Using the data measured in this controlled environment, we extracted the stiffness of the trapped particles and calculated their force. This study not only provides a simple and high-throughput method to measure the trap stiffness of multiple particles inside a microfluidic device using DEP tweezers but also inspires the application of the trapped multiple particles to investigate the dynamics in molecular interactions.

Three-dimensional isotropic T2-weighted fast spin-echo (VISTA) ankle MRI versus two-dimensional fast spin-echo T2-weighted sequences for the evaluation of anterior talofibular ligament injury

AIM

To compare the performance of axial images of the ankle joint on three-dimensional (3D) volume isotropic turbo spin echo acquisition (VISTA) with that of two-dimensional (2D) fast spin echo (FSE) T2-weighted images for the diagnosis of anterior talofibular ligament (ATFL) injury.

MATERIALS AND METHODS

This retrospective study included 101 patients who underwent both 2D FSE T2-weighted and 3D VISTA magnetic resonance imaging (MRI) of the ankle. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of both sequences were measured. The anatomical identification score and diagnostic performances of both sequences were evaluated by two radiologists. The diagnostic performances of 3D VISTA and 2D FSE images were analysed in terms of sensitivity, specificity, and accuracy for diagnosing ATFL injury. Surgically or clinically confirmed diagnoses were used as reference standards.

RESULTS

The margin sharpness scores on 3D VISTA were significantly inferior to those of 2D FSE (p<0.001). Other scores (entire length, entire width) were not significantly different between the two imaging methods. The SNRs and CNRs of 3D VISTA were significantly higher than those of 2D FSE (p<0.001). When diagnoses were classified as normal and abnormal, the specificity of the 3D VISTA images for the diagnosis of ATFL injury was 95.7%, significantly superior to 2D FSE (84.3-85.7%). There were no significant differences between 3D VISTA and 2D FSE images in sensitivity or accuracy for diagnosis (p=0.227-1.000), with the exception of accuracy by reader 1 (p=0.039).

CONCLUSION

3D VISTA imaging has a diagnostic performance comparable to that of 2D FSE for the diagnosis of ATFL injury, although 3D VISTA is inferior to 2D FSE for the evaluation of margin sharpness. Replacing axial and coronal images with 3D VISTA can save imaging time without negatively impacting the diagnostic ability for ATFL injury.

Corrigendum. Platelet-rich plasma for arthroscopic repair of medium to large rotator cuff tears: a randomized controlled trial

Jo CH, Shin JS, Shin WH, Lee SY, Yoon KS, Shin S. Platelet-rich plasma for arthroscopic repair of medium to large rotator cuff tears: a randomized controlled trial. Am J Sports Med. 2015 43(9):2102-2110. (Original DOI: 10.1177/0363546515587081 )

Leptin protects rat articular chondrocytes from cytotoxicity induced by TNF-α in the presence of cyclohexamide

OBJECTIVE

Although leptin appears to be an important local and systemic factor influencing cartilage homeostasis, the role of leptin in chondrocyte death is largely unknown. Tumor necrosis factor α (TNF-α) is a pro-inflammatory cytokine that plays a central role in the pathogenesis of articular diseases. This study examines whether leptin modulates TNF-α-induced articular chondrocyte death.

METHODS

Primary rat articular chondrocytes were isolated from knee joint cartilage slices. To induce cell death, the chondrocytes were treated with TNF-α. To examine whether leptin modulates the extent of TNF-α-mediated chondrocyte death, the cells were pretreated with leptin for 3 h before TNF-α treatment followed by viability analysis. To examine the mechanism by which leptin modulates the extent of TNF-α-mediated chondrocyte death, we utilized mitochondrial membrane potential (MMP) measurements, flow cytometry, nuclear morphology observation, co-immunoprecipitation, western blot analysis and confocal microscopy.

RESULTS

We demonstrated that leptin suppresses TNF-α induced chondrocyte death. We further found that apoptosis partially contributes to TNF-α induced chondrocyte death while necroptosis primarily contributes to TNF-α induced chondrocyte death. In addition, we observed that leptin exerts anti-TNF-α toxicity via c-jun N-terminal kinase (JNK) in rat articular chondrocytes.

CONCLUSION

Based on our findings, we suggest that the leptin present in the articular joint fluid protects articular chondrocytes against cumulative mechanical load and detrimental stresses throughout a lifetime, delaying the onset of degenerative changes in chondrocytes. We can further hypothesize that leptin protects articular chondrocytes against destructive stimuli even in the joints of osteoarthritis (OA) patients.

Low serum magnesium is associated with coronary artery calcification in a Korean population at low risk for cardiovascular disease

BACKGROUND AND AIMS

Previous studies suggested an association between low serum magnesium levels and metabolic or cardiovascular disease. Additionally, several studies have shown that low serum magnesium is associated with vascular calcification, but there are no studies exploring its relation to coronary artery calcification (CAC). We investigated the relationship between low serum magnesium and CAC by using health examination data.

METHODS AND RESULTS

We cross-sectionally analyzed 34,553 participants who underwent coronary multi-detector computed tomography and serum magnesium level measurement in 2010-2012 as part of a health examination program at a tertiary hospital in Korea. CAC was defined as a coronary artery calcium score > 100. Participants were divided into three groups according to their serum magnesium level as follows: low < 1.9 mg/dL (n = 931), normal = 1.9-2.3 mg/dL (n = 32,341), and high > 2.3 mg/dL (n = 1281). The percentages of participants with CAC were 3.7, 1.5, and 2.3 in each group, respectively. According to multivariate analysis, low serum magnesium was associated with CAC after adjustment for age, sex, BMI, diabetes, hypertension, cardiovascular disease, systolic BP, LDL cholesterol, HDL cholesterol, eGFR, serum calcium and phosphorus, hsCRP, current smoking status, alcohol intake and vigorous exercise frequency. The odds ratio for CAC in the low serum magnesium group compared to the normal group was 2.10 (1.40-3.15, P < 0.001).

CONCLUSION

Low serum magnesium level is associated with CAC in a Korean population at low risk for cardiovascular disease. Further studies are needed to generalize this finding and to verify the causal relationship between low serum magnesium and CAC.

Profiling microRNA expression in fracture nonunions: Potential role of microRNAs in nonunion formation studied in a rat model

MicroRNAs (miRNAs ) are small non-coding RNAs that regulate gene expression. We hypothesised that the functions of certain miRNAs and changes to their patterns of expression may be crucial in the pathogenesis of nonunion. Healing fractures and atrophic nonunions produced by periosteal cauterisation were created in the femora of 94 rats, with 1:1 group allocation. At post-fracture days three, seven, ten, 14, 21 and 28, miRNAs were extracted from the newly generated tissue at the fracture site. Microarray and real-time polymerase chain reaction (PCR) analyses of day 14 samples revealed that five miRNAs, miR-31a-3p, miR-31a-5p, miR-146a-5p, miR-146b-5p and miR-223-3p, were highly upregulated in nonunion. Real-time PCR analysis further revealed that, in nonunion, the expression levels of all five of these miRNAs peaked on day 14 and declined thereafter. Our results suggest that miR-31a-3p, miR-31a-5p, miR-146a-5p, miR-146b-5p and miR-223-3p may play an important role in the development of nonunion. These findings add to the understanding of the molecular mechanism for nonunion formation and may lead to the development of novel therapeutic strategies for its treatment.

Gluconacetobacter sp. gel_SEA623-2, bacterial cellulose producing bacterium isolated from citrus fruit juice

Cellulose producing bacterial strain was isolated from citrus fruit juice fungus. The isolated strain was identified as Gluconacetobacter sp. gel_SEA623-2 based on several morphological characteristics, biochemical tests, and 16S rRNA conducted. Culture conditions for bacterial cellulose production by SEA623-2 were screened in static trays. Conditions were extensively optimized by varying the kind of fruit juice, pH, sugar concentration, and temperature for maximum cellulose production. SEA623-2 has a high productive capacity in citrus processing medium, but not in other fruits. The optimal combination of the media constituents for bacterial cellulose production is as follows: 10% citrus juice, 10% sucrose, 1% acetic acid, and 1% ethanol at 30 °C, pH 3.5. Bacterial cellulose produced by SEA623-2 has soft physical properties, high tensile strength, and high water retention value. The cellulose produced by the selected bacteria is suitable as a cosmetic and medical material.

Comprehensive studies of hydrogeochemical processes and quality status of groundwater with tools of cluster, grouping analysis, and fuzzy set method using GIS platform: a case study of Dalcheon in Ulsan City, Korea

This research aimed at developing comprehensive assessments of physicochemical quality of groundwater for drinking and irrigation purposes at Dalcheon in Ulsan City, Korea. The mean concentration of major ions represented as follows: Ca (94.3 mg/L) > Mg (41.7 mg/L) > Na (19.2 mg/L) > K (3.2 mg/L) for cations and SO4 (351 mg/L) > HCO3 (169 mg/L) > Cl (19 mg/L) for anions. Thematic maps for physicochemical parameters of groundwater were prepared, classified, weighted, and integrated in GIS method with fuzzy logic. The maps exhibited that suitable zone of drinking and irrigation purpose occupied in SE, NE, and NW sectors. The undesirable zone of drinking purpose was observed in SW and central parts and that of irrigation was in the western part of the study area. This was influenced by improperly treated effluents from an abandoned iron ore mine, irrigation, and domestic fields. By grouping analysis, groundwater types were classified into Ca(HCO3)2, (Ca,Mg)Cl2, and CaCl2, and CaHCO3 was the most predominant type. Grouping analysis also showed three types of irrigation water such as C1S1, C1S2, and C1S3. C1S3 type of high salinity to low sodium hazard was the most dominant in the study area. Equilibrium processes elucidated the groundwater samples were in the saturated to undersaturated condition with respect to aragonite, calcite, dolomite, and gypsum due to precipitation and deposition processes. Cluster analysis suggested that high contents of SO4 and HCO3 with low Cl was related with water-rock interactions and along with mining impact. This study showed that the effluents discharged from mining waste was the main sources of groundwater quality deterioration.

Delayed diagnosis of cholestatic drug-induced liver injury treated with corticosteroid for adrenal insufficiency secondary to miliary tuberculosis

Drug-induced liver injury (DILI) in a patient with multiple comorbidities is often challenging to diagnose because liver injury can be attributed to multiple disease processes. Delayed treatment of DILI could have fatal consequences and, therefore, understanding the features and risks of DILI is crucial. We report a unique case of a patient who was admitted for severe sepsis of unknown etiology. This patient was later found to have miliary tuberculosis (TB) with associated adrenal insufficiency, complicated by acute cholestatic liver injury. Liver injury fully improved after initiation of corticosteroid for the treatment of adrenal insufficiency. The most likely pathophysiology of acute liver injury was DILI, given the clinical course of liver injury and the liver biopsy result of non-caseating granulomas. Although five different antibiotics including ciprofloxacin, metronidazole, vancomycin, imipenem/cilastatin, and cefepime were provided, the timing of liver injury and pharmacology of each drug imply that ciprofloxacin was the most likely antibiotic causing DILI, given the pharmacology of each antibiotics. This case is unique because miliary TB was complicated by adrenal insufficiency and drug-induced cholestatic liver injury, but acute liver injury was fully reversed after corticosteroid treatment. This implies an immune-mediated etiology of DILI, especially ciprofloxacin-induced cholestatic liver injury. DILI is challenging to diagnose in the setting of multiple comorbidities. Therefore, it is crucial that clinicians are to be aware of signs and symptoms of DILI, in that delayed diagnose and treatment may have fatal consequences.

Real-Time Analysis of Cellular Response to Small-Molecule Drugs within a Microfluidic Dielectrophoresis Device

Quantitative detection of the biological properties of living cells is essential for a wide range of purposes, from the understanding of cellular characteristics to the development of novel drugs in nanomedicine. Here, we demonstrate that analysis of cell biological properties within a microfluidic dielectrophoresis device enables quantitative detection of cellular biological properties and simultaneously allows large-scale measurement in a noise-robust and probeless manner. Applying this technique, the static and dynamic biological responses of live B16F10 melanoma cells to the small-molecule drugs such as N-ethylmaleimide (NEM) and [(dihydronindenyl)oxy]alkanoic acid (DIOA) were quantitatively and statistically examined by investigating changes in movement of the cells. Measurement was achieved using subtle variations in dielectrophoresis (DEP) properties of the cells, which were attributed to activation or deactivation of K(+)/Cl(-) cotransporter channels on the cell membrane by the small-molecule drugs, in a microfluidic device. On the basis of quantitative analysis data, we also provide the first report of the shift of the complex permittivity of a cell induced by the small-molecule drugs. In addition, we demonstrate interesting quantifiable parameters including the drug effectiveness coefficient, antagonistic interaction coefficient, kinetic rate, and full width at half-maximum, which corresponded to changes in biological properties of B16F10 cells over time when NEM and DIOA were introduced alone or in combination. Those demonstrated parameters represent very useful tools for evaluating the effect of small-molecule drugs on the biological properties of cells.

A genetic variation in microRNA target site of KRT81 gene is associated with survival in early-stage non-small-cell lung cancer

BACKGROUND

MicroRNAs (miRNAs) have a key role in carcinogenesis through negative regulation of their target genes. Therefore, genetic variations in miRNAs or their target sites may affect miRNA-mRNA interactions, thereby result in altered expression of target genes. This study was conducted to investigate the associations between single-nucleotide polymorphisms (SNP) located in the miRNA target sites (poly-miRTSs) and survival of patients with early-stage non-small-cell lung cancer (NSCLC).

METHODS

Using public SNP database and miRNA target sites prediction program, 354 poly-miRTSs were selected for genotyping. Among these, 154 SNPs applicable to Sequenom's MassARRAY platform were investigated in 357 patients. A replication study was carried out on an independent patient population (n = 479). Renilla luciferase assay and reverse transcription-polymerase chain reaction were conducted to examine functional relevance of potentially functional poly-miRTSs.

RESULTS

Of the 154 SNPs analyzed in a discovery set, 14 SNPs were significantly associated with survival outcomes. Among these, KRT81 rs3660G>C was found to be associated with survival outcomes in the validation cohort. In the combined analysis, patients with the rs3660 GC + CC genotype had a significantly better overall survival compared with those with GG genotype [adjusted hazard ratio (aHR) for OS, 0.65; 95% confidence interval (CI) 0.50-0.85; P = 0.001]. An increased expression of the reporter gene for the C allele of rs3660 compared with the G allele was observed by luciferase assay. Consistently, the C allele was associated with higher relative expression level of KRT81 in tumor tissues.

CONCLUSION

The rs3660G>C affects KRT81 expression and thus influences survival in early-stage NSCLC. The analysis of the rs3660G>C polymorphism may be useful to identify patients at high risk of a poor disease outcome.

Lower serum zinc levels are associated with unhealthy metabolic status in normal-weight adults: The 2010 Korea National Health and Nutrition Examination Survey

AIM

This study investigated whether serum zinc concentration is associated with glucose tolerance, insulin resistance and metabolic health status in Korean adults.

METHODS

Subjects with available serum zinc levels were recruited from the fifth Korea National Health and Nutrition Examination Survey (KNHANESV) cohort. Those in the highest quartile on homoeostasis model assessment for insulin resistance (HOMA-IR) and with a body mass index (BMI) of 18.5-25kg/m(2) were classified as metabolically obese and normal weight (MONW).

RESULTS

A total of 1813 subjects with a mean age of 45.2±0.5 years and a mean BMI of 24.01±0.11kg/m(2) were enrolled. Those in the lower serum zinc quartiles exhibited higher levels of fasting blood glucose and insulin resistance indices compared with those in the higher quartiles. However, these associations were positive only in normal-weight subjects. Those categorized as MONW exhibited significantly lower serum zinc levels than the metabolically healthy and normal weight (MHNW) subjects (131.6±3.0μg/dL vs 141.7±2.8μg/dL, respectively; P=0.0026), whereas serum zinc levels did not differ according to metabolic health in obese subjects. The odds ratio for being categorized as MONW was 4.12 (95% CI: 1.75, 9.72) among those in the lowest serum zinc quartile compared with those in the highest quartile even after adjusting for possible confounding factors.

CONCLUSION

Lower serum zinc levels were associated with unhealthy metabolic status in normal-weight adults. Further prospective studies are required to define the role of zinc in metabolic health.

Reliability and validity of lower extremity computed tomography as a screening tool for osteoporosis

We evaluated the correlation between central bone mineral density (BMD) and peripheral bone attenuation using lower extremity computed tomography (CT). A good correlation was found between lower extremity CT and central BMD suggesting that CT is useful for screening osteoporosis, and that peripheral bone attenuation adequately reflects central BMD.

INTRODUCTION

This study aimed to evaluate the reliability and validity of CT as a screening tool for osteoporosis and to estimate the correlation between central BMD and peripheral bone attenuation using lower extremity CT.

METHODS

In total, 292 patients who underwent a lower extremity, lumbar spine, or abdomen and pelvic CT scan within a 3-month interval of a dual-energy X-ray absorptiometry (DEXA) examination were included. Following reliability testing, bone attenuation of the L1, L2, L3, L4, femoral head, femoral neck, greater trochanter, distal femur, proximal tibia, distal tibia, and talus was measured by placing a circular region of interest on the central part of each bony region on a coronal CT image. Partial correlation was used to assess the correlation between CT and DEXA after adjusting for age and body mass index.

RESULTS

In terms of reliability, all bone attenuation measurements, except the femoral neck, showed good to excellent interobserver reliability (intraclass correlation coefficients, 0.691-0.941). In terms of validity, bone attenuation of the L1 to L4, femoral neck, and greater trochanter on CT showed significant correlations with BMD of each area on DEXA (correlation coefficients, 0.399-0.613). Bone attenuation of the distal tibia and talus on CT showed significant correlations with BMD of all parts on DEXA (correlation coefficients, 0.493-0.581 for distal tibia, 0.396-0.579 for talus).

CONCLUSION

Lower extremity CT is a useful screening tool for osteoporosis, and peripheral bone attenuation on lower extremity CT adequately reflects central BMD on DEXA.

Strain elastography features of epidermoid tumours in superficial soft tissue: differences from other benign soft-tissue tumours and malignant tumours

OBJECTIVE

We evaluated ultrasonographic features of superficial epidermoid tumour with a focus on strain elastography (SE) features that will help in the differential diagnosis of epidermoid tumour from other benign and malignant soft-tissue tumours.

METHODS

We retrospectively evaluated ultrasonographic and SE data of 103 surgically confirmed superficial soft-tissue tumours and tumour-like lesions: 29 cases of epidermoid tumour, 46 cases of other benign tumours and 28 cases of malignant tumour. SE and B-mode imaging were performed at the same time. SE characteristics were assigned into four grades (1-4) according to their elasticity. Interobserver agreement for the four SE scores between the two radiologists was analysed using kappa statistics. We classified each SE finding as a hard lesion (SE Score 3-4) or soft lesion (SE Score 1-2) and compared these findings using the χ(2) test to identify whether a significant difference in mass hardness existed among epidermoid tumour, other benign tumour and malignant tumour.

RESULTS

Overall interobserver agreement according to the four SE scores was moderate (κ = 0.540), and overall agreement for the hardness [soft (Score 1-2) or hard (Score 3-4)] was almost perfect (κ = 0.825). Malignant tumours showed higher SE scores (3-4, hard nature) than did epidermoid tumour or other benign soft-tissue tumours. There were no differences in SE score between epidermoid tumour and other benign tumours.

CONCLUSION

Superficial epidermoid tumour exhibits a softer nature than does malignant tumour but does not have a different SE pattern from other benign tumours.

ADVANCES IN KNOWLEDGE

SE features of epidermoid tumour might be helpful in differentiating from other benign and malignant tumours.