Threshold of Quantitative Cytomegalovirus DNA PCR for Preemptive Treatment in Pediatric Hematopoietic Stem Cell Transplant Recipients.

BACKGROUND: Consensus cytomegalovirus (CMV) DNA viral load thresholds for intervention in hematopoietic stem cell transplant (HSCT) recipients have not been established, especially in children. This study aimed at obtaining viral load thresholds of CMV DNA to guide preemptive management in pediatric HSCT recipients. MATERIALS AND METHODS: A total of 465 blood samples from 177 children who received HSCT between 2015 and 2019 were included in a single center in Korea. The samples were analyzed for CMV infection by both antigenemia assay and quantitative DNA polymerase chain reaction. The 2 assay results were compared for the 233 samples which were collected when antiviral treatment has not been initiated. We determined the viral loads corresponding to the antigenemia of 5 pp65-positive cells/2×10 5 white blood cells (WBCs) as the level for initiating preemptive therapy. RESULTS: Sixty percent of the samples were collected within 100 days (39.7% in 0 to 50 d, 60.2% in 0 to 100 d) from the graft infusion. The correlation between CMV DNA viral load and CMV antigenemia level increased significantly after 50 days from the graft infusion ( r =0.71 vs. r =0.93, P <0.0001). The correlation was greater in the antiviral treatment-naive group than the treatment group ( r =0.75 vs. r =0.66, P <0.0001). Under receiver operating characteristic curve analysis of the treatment-naive group, the estimated threshold CMV DNA viral loads corresponding to 5 pp65-positive cells/2×10 5 WBCs was 898 IU/mL. CONCLUSIONS: The CMV DNA levels that corresponded to 5 pp65-positive cells/2×10 5 WBCs was 900 IU/mL in the HSCT group. The proposed viral load thresholds can be used to guide preemptive therapy in pediatric HSCT recipients, especially in the preengraftment period.

Concentration Gradient Induced Delithiation Failure of MoO3 for Li-Ion Batteries.

Electric vehicle manufacturers worldwide are demanding superior lithium-ion batteries, with high energy and power densities, compared to gasoline engines. Although conversion-type metal oxides are promising candidates for high-capacity anodes, low initial Coulombic efficiency (ICE) and poor capacity retention have hindered research on their applications. In this study, the ICE of conversion-type MoO3 is investigated, with a particular focus on the delithiation failure. A computational modeling predicts the concentration gradient of Li+ in MoO3 particles. The highly delithiated outer region of the particle forms a layer with low electronic conductivity, which impedes further delithiation. A comparative study using various sizes of MoO3 particles demonstrated that the electrode failure during delithiation is governed by the concentration gradient and the subsequent formation of a resistive shell. The proposed failure mechanism provides critical guidance for the development of conversion-type anode materials with improved electrochemical reversibility.

S6K1 controls epigenetic plasticity for the expression of pancreatic α/ß cell marker genes.

The failure of insulin production by pancreatic ß cells is a common hallmark of type 1 diabetes mellitus (T1DM). Because administration of exogenous insulin is associated with diabetes-derived complications, endogenous α to ß cell transition can be an attractive alternative. Although decreased ß cell size and hypoinsulinaemia have been observed in S6K1-deficient mice, the molecular mechanism underlying the involvement of S6K1 in the transcriptional regulation of insulin remains elusive. Here, we show that the hypoinsulinaemic phenotype of S6K1-deficient mice stems from the dysregulated transcription of a set of genes required for insulin and glucagon production. First, we observed that increased expression of α cell marker genes and decreased expression of ß cell marker genes in pancreas tissues from S6K1-deficient mice. Furthermore, S6K1 was highly activated in murine ß cell line, ßTC6, compared to murine α cell line αTC1. In both α and ß cells, active S6K1 promoted the transcription of ß cell marker genes, including insulin, whereas S6K1 inhibition increased the transcription of α cell marker genes. Moreover, S6K1 mediated pancreatic gene regulation by modifying two histone marks (activating H3K4me3 and repressing H3K27me3) on gene promoters. These results suggest that S6K1 drives the α to ß transition through the epigenetic regulation of cell-specific genes, including insulin and glucagon. This novel role of S6K1 in islet cells provides basic clues to establish therapeutic strategies against T1DM.

Estimation of heritability and genetic correlation of body weight gain and growth curve parameters in Korean native chicken.

OBJECTIVE: This study estimated the genetic parameters for body weight gain and growth curve parameter traits in Korean native chicken (KNC). METHODS: A total of 585 F1 chickens were used along with 88 of their F0 birds. Body weights were measured every 2 weeks from hatching to 20 weeks of age to measure weight gain at 2-week intervals. For each individual, a logistic growth curve model was fitted to the longitudinal growth dataset to obtain three growth curve parameters (α, asymptotic final body weight; ß, inflection point; and γ, constant scale that was proportional to the overall growth rate). Genetic parameters were estimated based on the linear-mixed model using a restricted maximum likelihood method. RESULTS: Heritability estimates of body weight gain traits were low to high (0.057 to 0.458). Heritability estimates for α, ß, and γ were 0.211±0.08, 0.249±0.09, and 0.095±0.06, respectively. Both genetic and phenotypic correlations between weight gain traits ranged from -0.527 to 0.993. Genetic and phenotypic correlation between the growth curve parameters and weight gain traits ranged from -0.968 to 0.987. CONCLUSION: Based on the results of this study population, we suggest that the KNC could be used for selective breeding between 6 and 8 weeks of age to enhance the overall genetic improvement of growth traits. After validation of these results in independent studies, these findings will be useful for further optimization of breeding programs for KNC.

High-Ni cathode material improved with Zr for stable cycling of Li-ion rechargeable batteries.

The Zr solvent solution method, which allows primary and secondary particles of LiNi0.90Co0.05Mn0.05O2 (NCM) to be uniformly doped with Zr and simultaneously to be coated with an Li2ZrO3 layer, is introduced in this paper. For Zr doped NCM, which is formed using the Zr solvent solution method (L-NCM), most of the pinholes inside the precursor disappear owing to the diffusion of the Zr dopant solution compared with Zr-doped NCM, which is formed using the dry solid mixing method from the (Ni0.90Co0.05Mn0.05)(OH)2 precursor and the Zr source (S-NCM), and Li2ZrO3 is formed at the pinhole sites. The mechanical strength of the powder is enhanced by the removal of the pinholes by the formation of Li2ZrO3 resulting from diffusion of the solvent during the mixing process, which provides protection from cracking. The coating layer functions as a protective layer during the washing process for removing the residual Li. The electrochemical performance is improved by the synergetic effects of suitable coatings and the enhanced structural stability. The capacity-retentions for 2032 coin cells are 86.08%, 92.12%, and 96.85% at the 50th cycle for pristine NCM, S-NCM, and L-NCM, respectively. The superiority of the liquid mixing method is demonstrated for 18 650 full cells. In the 300th cycle in the voltage range of 2.8-4.35 V, the capacity-retentions for S-NCM and L-NCM are 77.72% and 81.95%, respectively.

The preliminary study for three-dimensional alveolar bone morphologic characteristics for alveolar bone restoration.

BACKGROUND: The concept of the ideal morphology for the alveolar bone form is an important element to reconstruct or restore the in maximizing esthetic profile and functional alveolar bone restoration. The purpose of this preliminary study is to evaluate the normal alveolar bone structure to provide the standard reference and guide template for use in diagnosing for implant placement, determining the correct amount of bone augmentation in actual clinical practice and producing prostheses based on three-dimensional imaging assessment of alveolar bone. METHODS: This study was included 11 men and 11 women (average age, 22.6 and 24.5 years, respectively) selected from among 127 patients. The horizontal widths of alveolar bone of maxilla and mandible were measured at the crestal, mid-root, and root apex level on MDCT (multi-detector computed tomography) images reconstructed by medical imaging software. In addition, tooth dimensions of the central incisors, canines, second premolars, and first molars of maxilla and mandible, including the horizontal width of the interdental alveolar bone crest, were also measured and statistically analyzed. RESULTS: The horizontal alveolar bone width of the palatal side of maxilla showed a distinct increment from the alveolar bone crest to the apical region in both anterior and posterior areas. The average widths of the maxillary alveolar ridge were as follows: central incisor, 7.43 mm; canine, 8.91 mm; second premolar, 9.57 mm; and first molar, 12.38 mm. The average widths of the mandibular alveolar ridge were as follows: central incisor, 6.21 mm; canine, 8.55 mm; second premolar, 8.45 mm; and first molar, 10.02 mm. In the buccal side, the alveolar bone width was not increased from the crest to the apical region. The horizontal alveolar bone width of an apical and mandibular border region was thinner than at the mid-root level. CONCLUSIONS: The results of the preliminary study are useful as a clinical guideline when determining dental implant diameter and position. And also, these measurements can also be useful during the production of prefabricated membranes and customized alveolar bone scaffolds.

An accurate method for quantifying and analyzing copy number variation in porcine KIT by an oligonucleotide ligation assay.

BACKGROUND: Aside from single nucleotide polymorphisms, copy number variations (CNVs) are the most important factors in susceptibility to genetic disorders because they affect expression levels of genes. In previous studies, pyrosequencing, mini-sequencing, real-time PCR, invader assays and other techniques have been used to detect CNVs. However, the higher the copy number in a genome, the more difficult it is to resolve the copies, so a more accurate method for measuring CNVs and assigning genotype is needed. RESULTS: PCR followed by a quantitative oligonucleotide ligation assay (qOLA) was developed for quantifying CNVs. The accuracy and precision of the assay were evaluated for porcine KIT, which was selected as a model locus. Overall, the root mean squares of bias and standard deviation of qOLA were 2.09 and 0.45, respectively. These values are less than half of those in the published pyrosequencing assay for analyzing CNV in porcine KIT. Using a combined method of qOLA and another pyrosequencing for quantitative analysis of KIT copies with spliced forms, we confirmed the segregation of KIT alleles in 145 F1 animals with pedigree information and verified the correct assignment of genotypes. In a diagnostic test on 100 randomly sampled commercial pigs, there was perfect agreement between the genotypes obtained by grouping observations on a scatter plot and by clustering using the nearest centroid sorting method implemented in PROC FASTCLUS of the SAS package. In a test on 159 Large White pigs, there were only two discrepancies between genotypes assigned by the two clustering methods (98.7% agreement), confirming that the quantitative ligation assay established here makes genotyping possible through the accurate measurement of high KIT copy numbers (>4 per diploid genome). Moreover, the assay is sensitive enough for use on DNA from hair follicles, indicating that DNA from various sources could be used. CONCLUSION: We have established a high resolution quantification method using an oligonucleotide ligation assay to measure CNVs, and verified the reliability of genotype assignment for random animal samples using the nearest centroid sorting method. This new method will make it more practical to determine KIT CNV and to genotype the complicated Dominant White/KIT locus in pigs. This procedure could have wide applications for studying gene or segment CNVs in other species.

Chemically Driven Enhancement of Oxygen Reduction Electrocatalysis in Supported Perovskite Oxides.

Perovskite oxides have the capacity to efficiently catalyze the oxygen reduction reaction (ORR), which is of fundamental importance for electrochemical energy conversion. While the perovskite catalysts have been generally utilized with a support, the role of the supports, regarded as inert toward the ORR, has been emphasized mostly in terms of the thermal stability of the catalyst system and as an ancillary transport channel for oxygen ions during the ORR. We demonstrate a novel approach to improving the catalytic activity of perovskite oxides for solid oxide fuel cells by controlling the oxygen-ion conducting oxide supports. Catalytic activities of (La0.8Sr0.2)0.95MnO3 perovskite thin-film placed on different oxide supports are characterized by electrochemical impedance spectroscopy and X-ray absorption spectroscopy. These analyses confirm that the strong atomic orbital interactions between the support and the perovskite catalyst enhance the surface exchange kinetics by ∼2.4 times, in turn, improving the overall ORR activity.

Coupling between oxygen redox and cation migration explains unusual electrochemistry in lithium-rich layered oxides.

Lithium-rich layered transition metal oxide positive electrodes offer access to anion redox at high potentials, thereby promising high energy densities for lithium-ion batteries. However, anion redox is also associated with several unfavorable electrochemical properties, such as open-circuit voltage hysteresis. Here we reveal that in Li1.17-x Ni0.21Co0.08Mn0.54O2, these properties arise from a strong coupling between anion redox and cation migration. We combine various X-ray spectroscopic, microscopic, and structural probes to show that partially reversible transition metal migration decreases the potential of the bulk oxygen redox couple by > 1 V, leading to a reordering in the anionic and cationic redox potentials during cycling. First principles calculations show that this is due to the drastic change in the local oxygen coordination environments associated with the transition metal migration. We propose that this mechanism is involved in stabilizing the oxygen redox couple, which we observe spectroscopically to persist for 500 charge/discharge cycles.

Clinical Significance of the Levels of Serum Cholesterol in Patients with Gastric Cancer.

PURPOSE: The relationship between serum cholesterol levels and mortality is complex. Serum cholesterol levels correlate positively with coronary artery disease, but some studies have suggested a negative relationship in cancer patients. Because the serum cholesterol levels are one of the most frequently assayed laboratory values, trends in the levels of cholesterol were investigated, in patients with gastric cancer and assumed a possible role in cancer screening. MATERIALS AND METHODS: The serum cholesterol levels were retrospectively analyzed in a group of 220 patients, diagnosed with gastric cancer, and in 177 healthy subjects. Anthropometric (body mass index: BMI) and biochemical indices of their nutritional status were also determined in the study subjects. Statistical analyses were performed by analyses of variance and covariance, and a discriminant analysis. RESULTS: The levels of serum cholesterol, albumin, Hb and the BMI were significantly lower in the gastric cancer-patients group than in the healthy-subjects group. The serum cholesterol and Hb levels were shown to be independent of each other, when adjusted for the effects of the BMI. In the patients with gastric cancer the levels of cholesterol and Hb showed decreasing tendencies as did the tumor extension, as defined by the TNM system. CONCLUSION: The serum cholesterol and Hb levels were significantly lower in patients with gastric cancer than in the healthy subjects, which seemed to be linked to the progression of gastric cancer. Therefore, further study is required for the serum cholesterol and Hb levels to be used as markers in cancer screening and its progression, in patients with gastric cancer.