Enhanced mechanical properties of ZrO2-Al2O3 dental ceramic composites by altering Al2O3 form

OBJECTIVES

This study evaluates the difference in physical and mechanical properties of ZrO₂ ceramics, commonly used in dental applications, altered by three different forms of Al₂O₃ content; microparticles (m), nanoparticles (n), and microfiber (f).

METHODS

Three different types of ZrO₂-Al₂O₃ composites were formed using microparticle (m), nanoparticle (n), or microfibre (f) forms of Al₂O₃. The physical and mechanical properties such as sintering shrinkage, relative density, Vickers hardness, fracture toughness, and biaxial strength were evaluated. A Weibull analysis was performed to assess the strength reliability of the specimens. All data were calculated using the t-test and ANOVA.

RESULTS

The sintering shrinkage and relative density of all ceramic composite groups were decreased with the addition of Al₂O₃. The mechanical properties of ZrO₂-Al₂O₃ (f) composite were higher than that of ZrO₂-Al₂O₃ (m) composite and ZrO₂-Al₂O₃ (n) composite. The maximum hardness, fracture toughness, and biaxial flexural strength were observed for 10 vol% of Al₂O₃ fibre. When the content of Al₂O₃ fibre in the matrix was increased above 20 vol%, agglomeration occurred and resulted in a decrease of hardness and toughness. The Weibull modulus value of the ZrO₂-Al₂O₃ (f) composite was the lowest compared to that of other groups. However, characteristic strength (σ₀) of ZrO₂-Al₂O₃ (f) the highest value.

SIGNIFICANCE

The current study demonstrated that the addition of right amount of Al₂O₃ microfibre into the ZrO₂ matrix enhanced the mechanical properties of ZrO₂-Al₂O₃ (f) composite, which would be favourable for dental applications.

First identified Korean family with Tatton-Brown-Rahman Syndrome caused by the novel DNMT3A variant c.118G>C p.(Glu40Gln)

Tatton-Brown-Rahman Syndrome (TBRS), an overgrowth syndrome caused by heterozygous mutation of DNMT3A, first was described in 2014. Approximately 60 DNMT3A variants, including 32 missense variants, have been reported, with most missense mutations located on the DNMT3A functional domains. Autosomal dominant inheritance by germ-line mutation of DNMT3A has been reported, but vertical transmission within a family is extremely rare. Herein, we report the first Korean family with maternally inherited TBRS due to the novel heterozygous DNMT3A variant c.118G>C p.(Glu40Gln), located outside the main functional domain and identified by multigene panel sequencing. The patient and her mother had typical clinical features, including tall stature during childhood, macrocephaly, intellectual disability, and characteristic facial appearance. TBRS shows milder dysmorphic features than other overgrowth syndromes, potentially leading to underdiagnosis and underestimated prevalence; thus, targeted multigene panel sequencing including DNMT3A will be a useful tool in cases of overgrowth and unexplained mild intellectual disability for early diagnosis and genetic counseling.

Novel Poly(Methyl Methacrylate) Containing Nanodiamond to Improve the Mechanical Properties and Fungal Resistance

Herein we evaluate the effect of nanodiamond (ND) incorporation on the mechanical properties of poly(methyl methacrylate) (PMMA) nanocomposite. Three quantities of ND (0.1, 0.3, and 0.5 wt.%) were tested against the control and zirconium oxide nanoparticles (ZrO). Flexural strength and elastic modulus were measured using a three-point bending test, surface hardness was evaluated using the Vickers hardness test, and surface roughness was evaluated using atomic force microscopy (AFM), while fungal adhesion and viability were studied using Candida albicans. Samples were also analyzed for biofilm thickness and biomass in a saliva-derived biofilm model. All groups of ND-PMMA nanocomposites had significantly greater mean flexural strengths and statistically improved elastic modulus, compared to the control and ZrO groups (P < 0.001). The Vickers hardness values significantly increased compared to the control group (P < 0.001) with 0.3% and 0.5% ND. ND addition also gave significant reduction in fungal adhesion and viability (P < 0.001) compared to the control group. Finally, salivary biofilm formation was markedly reduced compared to the ZrO group. Hence, the incorporation of 0.1–0.5 wt.% ND with auto- polymerized PMMA resin significantly improved the flexural strength, elastic modulus, and surface hardness, and provided considerable fungal resistance.

6112Usefulness of the trans-stent fractional flow reserve gradient for predicting clinical outcomes

Aims

The clinical meaning of a trans-stent pressure gradient after DES implantation has not been estimated adequately. We evaluated the usefulness of a fractional flow reserve (FFR) gradient across the stent (ΔFFRstent) for long-term clinical outcomes after percutaneous coronary intervention (PCI) with a drug-eluting stent (DES).

Methods and results

FFR pull-back and intravascular ultrasound (IVUS) were performed after successful PCI in 135 left anterior descending artery lesions. ΔFFRstent was defined as the FFR gradient across the stent. The ΔFFRstent/length was defined as the ΔFFRstent value divided by the total stent length multiplied by 10 [= (ΔFFRstent ÷ stent length) x 10]. Major adverse cardiac events (MACEs) were the composite of all-cause death, target vessel related myocardial infarction, and target lesion revascularisation. Despite successful PCI without significant complications on IVUS, ΔFFRstent >0 was observed in 98.5% of cases. ΔFFRstent ≥0.04 and ΔFFRstent/length ≥0.009 predicted suboptimal stenting defined as final minimal stent area <5.5 mm2. During 2183±898 days, the MACE-free survival rate was significantly lower in patients with ΔFFRstent ≥0.04 and ΔFFRstent/length ≥0.009 compared to those with lower values (69.6 vs. 93.4%, log-rank p=0.031; 72.1 vs. 97.7%, log-rank p=0.003, respectively). ΔFFRstent/length ≥0.009 (hazard ratio 10.1, p=0.032) was an independent predictor of MACE.

Trans-stent FFR and MACE

Conclusion

A trans-stent FFR gradient was frequently observed in DES-treated patients despite successful PCI results. ΔFFRstent and ΔFFRstent/length are useful indicators for optimising a DES and are related to long-term outcomes.

Vaccinia-related kinase 2 plays a critical role in microglia-mediated synapse elimination during neurodevelopment

During postnatal neurodevelopment, excessive synapses must be eliminated by microglia to complete the establishment of neural circuits in the brain. The lack of synaptic regulation by microglia has been implicated in neurodevelopmental disorders such as autism, schizophrenia, and intellectual disability. Here we suggest that vaccinia-related kinase 2 (VRK2), which is expressed in microglia, may stimulate synaptic elimination by microglia. In VRK2-deficient mice (VRK2^KO ), reduced numbers of presynaptic puncta within microglia were observed. Moreover, the numbers of presynaptic puncta and synapses were abnormally increased in VRK2^KO mice by the second postnatal week. These differences did not persist into adulthood. Even though an increase in the number of synapses was normalized, adult VRK2^KO mice showed behavioral defects in social behaviors, contextual fear memory, and spatial memory.

DAP5 increases axonal outgrowth of hippocampal neurons by enhancing the cap-independent translation of DSCR1.4 mRNA

Proper wiring between neurons is indispensable for proper brain function. From the early developmental stage, axons grow and navigate to connect to targets according to specific guidance cues. The accuracy of axonal outgrowth and navigation are controlled by a variety of genes, and mutations and/or deficiencies in these genes are closely related to several brain disorders, such as autism. DSCR1 is one of these genes and regulates actin filament formation in axons. Thus, identifying the detailed regulatory mechanisms of DSCR1 expression is crucial for the understanding of the axon development of neurons; however, these regulatory mechanisms of DSCR1 remain unknown. Here, we discovered that mRNA encoding the DSCR1 isoform DSCR1.4 is present and mainly translated by the cap-independent initiation mechanisms in both the soma and axons of hippocampal neurons. We found that translation of DSCR1.4 mRNA is enhanced by death-associated protein 5 (DAP5), which can bind to DSCR1.4 5'UTR. BDNF-stimulus induced an increase in DAP5 expression and the cap-independent translation efficiency of DSCR1.4 mRNA in axon as well as soma. Furthermore, we showed the importance of the cap-independent translation of DSCR1.4 on enhancement of DSCR1.4 expression by BDNF-stimulus and axonal outgrowth of hippocampal neurons. Our findings suggest a new translational regulatory mechanism for DSCR1.4 expressions and a novel function of DAP5 as a positive regulator of DSCR1.4 mRNA translation induced in soma and axon of hippocampal neurons.

Upf1 regulates neurite outgrowth and branching by transcriptional and post-transcriptional modulation of Arc

A large number of neuronal proteins must show correct spatiotemporal localization in order to carry out their critical functions. The mRNA transcript for the somatodendritic protein activity-regulated cytoskeleton-associated protein (Arc; also known as Arg3.1) contains two conserved introns in the 3' untranslated region (UTR), and was proposed to be a natural target for nonsense-mediated mRNA decay (NMD). However, a well-known NMD component Upf1 has differential roles in transcriptional and translational regulation of Arc gene expression. Specifically, Upf1 suppresses Arc transcription by enhancing destabilization of mRNAs encoding various transcription factors, including Mef2a. Upf1 also binds to the Arc 3'UTR, resulting in suppression of translation. Surprisingly, the Arc transcript escapes from Upf1-mediated NMD by binding to Ago2 (also known as miRISC), which blocks NMD and further suppresses Arc mRNA translation. Upf1 knockdown triggered sustained Arc expression, which contributes to Cofilin (also known as Cfl1) hyperphosphorylation and abnormal neuronal outgrowth and branching. Collectively, these data reveal that multiple levels of Upf1-mediated inhibition of Arc gene expression may allow neurons to more effectively respond to changes in neuronal activity.

Changes of the growth plate in children: 3-dimensional magnetic resonance imaging analysis

PURPOSE

This pilot study assessed changes in the growth plate and growth rates in children during a 6-month period.

METHODS

The study included 31 healthy children (17 boys, 14 girls) under evaluation for growth retardation. Height, weight, bone age, insulin like growth factor-1 (IGF-1), and insulin like growth factor binding protein 3 (IGF-BP3) were measured at baseline and after 6 months. In addition, the diameter, thickness, and volume of the femoral and tibial growth plates were measured using magnetic resonance imaging.

RESULTS

The mean bone age in boys and girls was 11.7 and 10.7 years, respectively. In boys, height (z score) (-0.2 vs. 0.0), weight (z score) (0.8 vs. 1.1), body mass index (BMI) (z score) (1.27 vs. 1.5), IGF-1 (ng/mL) (343.6 vs. 501.8), and IGF-BP3 (ng/mL) (5,088.5 vs. 5,620.0) were significantly higher after 6 months. In girls, height (z score) (-1.0 vs. -0.7), weight (z score) (-0.5 vs. 0.1), BMI (z score) (-0.02 vs. 0.3), IGF-1 (ng/mL) (329.3 vs. 524.6), and IGF-BP3 (ng/mL) (4,644.4 vs. 5,593.6) were also significantly higher after 6 months. In both sexes, the mean diameter and volume of the femoral and tibial growth plates were significantly increased 6 months later.

CONCLUSION

No significant correlation was found between changes in the growth plate and clinical parameters in children with growth retardation in this study, other than correlations of change in femoral diameter with weight and BMI. A larger, long-term study is needed to precisely evaluate the correlation between change in the growth plate and growth.

Expansion microscopy

Super-resolution optical microscopy techniques have revolutionized how we see and understand biology. In recent past, a new super-resolution optical microscopy technique called expansion microscopy (ExM) was developed. Unlike other pre-existing super-resolution imaging techniques, this technique achieves super-resolution by physically expanding biological specimens via a swellable hydrogel. After the development of ExM, various techniques based on ExM but with improved performance in various aspects, have been developed. In this review, we introduce the basic principles of ExM and its variants. and compare the advantages and disadvantages of these techniques. In addition, we present the applications of ExM techniques in various fields.

ABO Mistyping of cis-AB Blood Group by the Automated Microplate Technique

Background

The cis-AB phenotype, although rare, is the relatively most frequent of ABO subgroups in Koreans. To prevent ABO mistyping of cis-AB samples, our hospital has applied a combination of the manual tile method with automated devices. Herein, we report cases of ABO mistyping detected by the combination testing system.

Methods

Cases that showed discrepant results by automated devices and the manual tile method were evaluated. These samples were also tested by the standard tube method. The automated devices used in this study were a QWALYS-3 and Galileo NEO. Exons 6 and 7 of the ABO gene were sequenced.

Results

13 cases that had the cis-AB allele showed results suggestive of the cis-AB subgroup by manual methods, but were interpreted as AB by either automated device. This happened in 87.5% of these cases by QWALYS-3 and 70.0% by Galileo NEO. Genotyping results showed that 12 cases were ABO*cis-AB01/ABO*O01 or ABO*cis-AB01/ABO*O02, and one case was ABO*cis-AB01/ ABO*A102.

Conclusion

Cis-AB samples were mistyped as AB by the automated microplate technique in some cases. We suggest that the manual tile method can be a simple supplemental test for the detection of the cis-AB phenotype, especially in countries with relatively high cis-AB prevalence.

Validation of surrogate markers for metabolic syndrome and cardiometabolic risk factor clustering in children and adolescents: A nationwide population-based study

Prevalence of metabolic syndrome (MetS) in children is increasing and identifying the risk factors for MetS during childhood is an important first step to prevent chronic diseases later in life. The aim of the present study was to evaluate the prevalence of MetS and cardiometabolic risk factor (CMRF) clustering among Korean children and adolescents and to validate the associated anthropometric and laboratory surrogate markers. We used data from the 2011–2014 Korean National Health and Nutrition Examination Survey. In total, data for 2,935 subjects (1539 boys, 52.6%) aged 10–19 years were assessed. MetS was defined by central obesity plus any two or more of CMRFs such as abdominal obesity, hypertension, hyperglycemia, hypertriglyceridemia, and decreased high density lipoprotein cholesterol (HDL-C) using the International Diabetes Federation criteria for children and adolescents. The presence of two or more CMRFs was classified as CMRF clustering. The prevalence of MetS and CMRF clustering in this group was found to be 1.8% and 8.9%, respectively. The receiver operating characteristic analysis of MetS and CMRF clustering, and the area under the curve (95% confidence interval) of surrogate markers revealed that the waist circumference to height ratio [0.960 (95% CI 0.959–0.960), cut-off 0.491] showed the highest predictability for MetS whereas triglyceride to HDL-C ratio [0.891 (95% CI 0.891–0.892), cut-off 2.63] showed the highest predictability for CMRF clustering. Long-term follow-up is needed for further validation.

Heterogeneous nuclear ribonucleoprotein (hnRNP) L promotes DNA damage-induced cell apoptosis by enhancing the translation of p53

The tumor suppressor p53 is an essential gene in the induction of cell cycle arrest, DNA repair, and apoptosis. p53 protein is induced under cellular stress, blocking cell cycle progression and inducing DNA repair. Under DNA damage conditions, it has been reported that post-transcriptional regulation of p53 mRNA contributes to the increase in p53 protein level. Here we demonstrate that heterogeneous nuclear ribonucleoprotein (hnRNP) L enhances p53 mRNA translation. We found that hnRNP L is increased and binds to the 5'UTR of p53 mRNA in response to DNA damage. Increased hnRNP L caused enhancement of p53 mRNA translation. Conversely, p53 protein levels were decreased following hnRNP L knock-down, rendering them resistant to apoptosis and arrest in the G2/M phase after DNA damage. Thus, our findings suggest that hnRNP L functions as a positive regulator of p53 translation and promotes cell cycle arrest and apoptosis.

Application of a portable microscopic cell counter for the counting of residual leukocytes in leukoreduced apheresis platelet concentrates in a hospital blood bank

While a portable microscopic cell counter has been evaluated to enumerate residual white blood cells (WBCs) in red blood cells and platelet concentrates at blood centers, it has not yet been assessed in a hospital blood bank. We investigated the performance of this device and evaluated its accuracy, along with its benefits in time management. Residual WBCs from each of 100 apheresis platelet specimens were measured manually using a Nageotte chamber, along with flow cytometry methods and an ADAM-rWBC automated instrument (NanoEnTek, Seoul, South Korea). The efficiency was calculated by measuring the time required for the analysis of one specimen ten times consecutively. Flow cytometry and the ADAM-rWBC were able to detect four sporadic cases that had residual WBCs exceeding 1/μL that were not detected by the manual method. Analysis time was the shortest with the ADAM-rWBC, followed by flow cytometry and the manual method. Our data suggest that hospital blood banks require quality control of residual WBCs; among the methods evaluated in this study, the portable microscopic cell counter offers the best time efficiency.

Relationship between School Violence and Depressive Symptoms among Multicultural Families' Offspring in South Korea

The aim of the study was to evaluate the effect of school violence on depressive symptoms among the offspring of multicultural families in South Korea. Data from the National Survey of Multicultural Families 2012, conducted by the Korean Women's Development Institute and Statistics Korea, were used in this study. Complex samples logistic regression was performed to determine the effect of school violence on depressive mood. The survey participants were 3999 students between the ages of 9 and 24. Of the participants, 22.1% reported experiencing depressive symptoms and 9.1% reported experiencing school violence within the last year. School violence was a strong risk factor (OR=5.142, 95% CI=4.067-6.500) for depressive symptoms after adjusting for personal, familial and school factors. School violence is a serious contributor to depressive mood among the offspring of multicultural families. There is a significant need to monitor school violence among this vulnerable group.

Contributions of CAG repeat length in the androgen receptor gene and androgen profiles to premature pubarche in Korean girls

The CAG repeat length of the androgen receptor (AR) gene, which exhibits an inverse relationship to AR sensitivity, might influence the development of the pubarche along with hyperandrogenemia. There are ethnic differences in the AR CAG repeat length, however, no Asian studies on premature pubarche (PP) have been reported, including Korea. Our objectives were to examine the hormone levels and AR CAG repeat length, and to assess their contributions to PP in Korean girls. Subjects with PP (n=16) and normal pubarche (NP, n=16), and normal controls (NC, n=16) were enrolled. The levels of dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEAS), 17-hydroxyprogesterone (17-OHP), and free testosterone (FT) were checked. The methylation-weighted (MW) average CAG repeat lengths were analyzed. The median ages at pubarche were 7.4 and 8.9 years in the PP and NP groups, respectively, and the levels of 17-OHP, DHEAS, and FT were similar in both groups. The PP group exhibited a higher DHEAS:DHEA ratio than the NP group (P=0.014). The medians of the MW average CAG repeat length of the AR gene were 22.4 for all subjects and did not differ among the PP (22.3), NP (22.4), and NC (22.2) groups. The AR CAG repeat lengths in the PP and NP groups did not correlate with DHEAS or FT levels. These results suggest that the AR CAG repeat length was not involved in the development of PP in Korean girls. However, excessive adrenal androgen levels, particularly those caused by increased sulfotransferase activity, might be important in the pathogenesis of PP.

The A312 Allele (c.280A>T) Is Responsible for the Weak A Phenotype

The ABO*A312 allele was found in a 71-year-old Korean male with ABO discrepancy and in his two sons. Although the ABO*A312 allele (c.280A>T, I94F) in an AwB case was registered in GenBank, the impact of the I94F mutation of the ABO gene on the activity of A transferase has not been studied. Transient transfection experiments were performed in HeLa cells using A101, A102, and A312 alleles synthesized by site-directed mutagenesis, and the functional expression level of A antigen was assessed by flow cytometry. The results showed that the A102 and A312 alleles expressed A antigen levels that were 80.28% and 19.32%, respectively, of that of the A101 allele. Our study results demonstrate that the c.280A>T variant is responsible for the weakened expression of A antigen.

First-Line Use of Core Needle Biopsy for High-Yield Preliminary Diagnosis of Thyroid Nodules

BACKGROUND AND PURPOSE

Although core needle biopsy was introduced as a diagnostic alternative to fine-needle aspiration, the utility and safety of core needle biopsy for thyroid nodules in a large population has yet to be studied comprehensively. We evaluate core needle biopsy yields on a large-scale basis to investigate its potential in the preliminary diagnosis of thyroid nodules.

MATERIALS AND METHODS

Between March 2005 and December 2013, 2448 initially detected thyroid nodules from 2120 consecutive patients who underwent core needle biopsy were retrospectively evaluated. Of these, 72 thyroid nodules from 63 patients were excluded due to prior fine-needle aspiration attempts. The inconclusive and conclusive result rates, diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and unnecessary surgery rate of core needle biopsy were evaluated.

RESULTS

With core needle biopsy as the first-line method, the inconclusive result rate was 11.9% (283/2376) and the conclusive result rate was 88.1% (2093/2376). The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of core needle biopsy for the diagnosis of malignancy were 96.7% (1160/1200), 89.7% (347/387), 100% (813/813), 100% (347/347), and 95.3% (813/853), respectively. There were no major complications and 12 minor complications.

CONCLUSIONS

We have demonstrated that first-line use of core needle biopsy may well improve diagnostic accuracy in thyroid nodules, reducing inconclusive or false-negative results and unnecessary operations. Such benefits underscore the promising role of core needle biopsy in managing thyroid nodules and optimizing related surgical decision-making.

Nanowires: Quantitative Probing of Cu(2+) Ions Naturally Present in Single Living Cells (Adv. Mater. 21/2016)

Quantitative probing of the Cu(2+) ions naturally present in single living cells is accomplished by a probe made from a quantum-dot-embedded-nanowire waveguide. After inserting the active nanowire-based waveguide probe into single living cells, J. H. Je and co-workers directly observe photoluminescence (PL) quenching of the embedded quantum dots by the Cu(2+) ions diffused into the probe as described on page 4071. This results in quantitative measurement of intracellular Cu(2+) ions.

Quantitative Probing of Cu(2+) Ions Naturally Present in Single Living Cells

Quantitative probing of Cu(2+) ions naturally present in single living cells is realized by developing a quantum-dot-embedded nanowire-waveguide probe. The intracellular Cu(2+) ion concentration is quantified by direct monitoring of photoluminescence quenching during the insertion of the nanowire in a living neuron. The measured intracellular Cu(2+) ion concentration is 3.34 ± 1.04 × 10(-6) m (mean ± s.e.m.) in single hippocampal neurons.

The Wnt/β-catenin signaling pathway regulates the development of airway remodeling in patients with asthma

Airway remodeling is a key characteristic of chronic asthma, particularly in patients with a fixed airflow limitation. The mechanisms underlying airway remodeling are poorly understood, and no therapeutic option is available. The Wnt/β-catenin signaling pathway is involved in various physiological and pathological processes, including fibrosis and smooth muscle hypertrophy. In this study, we investigated the roles of Wnt/β-catenin signaling in airway remodeling in patients with asthma. Wnt7a mRNA expression was prominent in induced sputum from patients with asthma compared with that from healthy controls. Next, we induced a chronic asthma mouse model with airway remodeling features, including subepithelial fibrosis and airway smooth muscle hyperplasia. Higher expression of Wnt family proteins and β-catenin was detected in the lung tissue of mice with chronic asthma compared to control mice. Blocking β-catenin expression with a specific siRNA attenuated airway inflammation and airway remodeling. Decreased subepithelial fibrosis and collagen accumulation in the β-catenin siRNA-treated mice was accompanied by reduced expression of transforming growth factor-β. We further showed that suppressing β-catenin in the chronic asthma model inhibited smooth muscle hyperplasia by downregulating the tenascin C/platelet-derived growth factor receptor pathway. Taken together, these findings demonstrate that the Wnt/β-catenin signaling pathway is highly expressed and regulates the development of airway remodeling in chronic asthma.

Parents' perception about child's height and psychopathology in community children with relatively short stature

PURPOSE

This study investigated the relationship between height and psychopathology in community children with relatively short stature according to the parents' reports. Also, the matter of parental concern about child's height was explored.

METHODS

The child behavior checklist (CBCL), the Brief Encounter Psychosocial Instrument (BEPSI), and the child-health questionnaire-parent form 50 (CHQ-PF50) were administered to 423 parents (from elementary and middle school children's) in Gangnam, South Korea. Subjects were divided into three groups; (1) relatively short (n=30), (2) average stature (n=131), (3) relatively tall (n=153). CBCL, BEPSI, and CHQ-PF50 scores were compared among three groups.

RESULTS

There were no significant differences in psychosocial burden associated with relatively short stature measured by Korean version of the BEPSI and Korean version of the CBCL scores among three groups. But general health perception score of relatively short was significantly lower than that of nonshort on the CHQ-PF50. Also, they were more used complementary medicines, milk and growth hormone compared to the nonshort. The parents' expected height of their children was 180.6±3.5 cm for boys and 166.7±3.5 cm for girls. This is respectively 90 percentile and 75-90 percentile for the Korean standard adult height.

CONCLUSION

Our study shows that in Korea, Parents tended to regard relatively short children as having health problems. Also, the parental expectation for their child's attainable height is unrealistically tall, mostly due to lack of correct medical information.

Performance evaluation of the new hematology analyzer Sysmex XN-series

INTRODUCTION

The Sysmex XN-series is a new automated hematology analyzer designed to improve the accuracy of cell counts and the specificity of the flagging events.

METHODS

The basic characteristics and the performance of new measurement channels of the XN were evaluated and compared with the Sysmex XE-2100 and the manual method. Fluorescent platelet count (PLT-F) was compared with the flow cytometric method. The low WBC mode and body fluid mode were also evaluated. For workflow analysis, 1005 samples were analyzed on both the XN and the XE-2100, and manual review rates were compared.

RESULTS

All parameters measured by the XN correlated well with the XE-2100. PLT-F showed better correlation with the flow cytometric method (r(2)  = 0.80) compared with optical platelet count (r(2)  = 0.73) for platelet counts <70 × 10(9) /L. The low WBC mode reported accurate leukocyte differentials for samples with a WBC count <0.5 × 10(9) /L. Relatively good correlation was found for WBC counts between the manual method and the body fluid mode (r = 0.88). The XN made less flags than the XE-2100, while the sensitivities of both instruments were comparable.

CONCLUSION

The XN provided reliable results on low cell counts, as well as reduced manual blood film reviews, while maintaining a proper level of diagnostic sensitivity.

Performance evaluation of the new hematology analyzer Sysmex XN-series

INTRODUCTION

The Sysmex XN-series is a new automated hematology analyzer designed to improve the accuracy of cell counts and the specificity of the flagging events.

METHODS

The basic characteristics and the performance of new measurement channels of the XN were evaluated and compared with the Sysmex XE-2100 and the manual method. Fluorescent platelet count (PLT-F) was compared with the flow cytometric method. The low WBC mode and body fluid mode were also evaluated. For workflow analysis, 1005 samples were analyzed on both the XN and the XE-2100, and manual review rates were compared.

RESULTS

All parameters measured by the XN correlated well with the XE-2100. PLT-F showed better correlation with the flow cytometric method (r(2)  = 0.80) compared with optical platelet count (r(2)  = 0.73) for platelet counts <70 × 10(9) /L. The low WBC mode reported accurate leukocyte differentials for samples with a WBC count <0.5 × 10(9) /L. Relatively good correlation was found for WBC counts between the manual method and the body fluid mode (r = 0.88). The XN made less flags than the XE-2100, while the sensitivities of both instruments were comparable.

CONCLUSION

The XN provided reliable results on low cell counts, as well as reduced manual blood film reviews, while maintaining a proper level of diagnostic sensitivity.