Use of dual genomic sequencing to screen mitochondrial diseases in pediatrics: a retrospective analysis

Mitochondrial diseases (MDs) were a large group multisystem disorders, attributable in part to the dual genomic control. The advent of massively sequencing has improved diagnostic rates and speed, and was increasingly being used as a first-line diagnostic test. Paediatric patients (aged < 18 years) who underwent dual genomic sequencing were enrolled in this retrospective multicentre study. We evaluated the mitochondrial disease criteria (MDC) and molecular diagnostic yield of dual genomic sequencing. Causative variants were identified in 177 out of 503 (35.2%) patients using dual genomic sequencing. Forty-six patients (9.1%) had mitochondria-related variants, including 25 patients with nuclear DNA (nDNA) variants, 15 with mitochondrial DNA (mtDNA) variants, and six with dual genomic variants (MT-ND6 and POLG; MT-ND5 and RARS2; MT-TL1 and NARS2; MT-CO2 and NDUFS1; MT-CYB and SMARCA2; and CHRNA4 and MT-CO3). Based on the MDC, 15.2% of the patients with mitochondria-related variants were classified as "unlikely to have mitochondrial disorder". Moreover, 4.5% of the patients with non-mitochondria-related variants and 1.43% with negative genetic tests, were classified as "probably having mitochondrial disorder". Dual genomic sequencing in suspected MDs provided a more comprehensive and accurate diagnosis for pediatric patients, especially for patients with dual genomic variants.

A Novel Signature of 23 Immunity-Related Gene Pairs Is Prognostic of Cutaneous Melanoma

In this study, we aimed to identify an immune-related signature for predicting prognosis in cutaneous melanoma (CM). Sample data from The Cancer Genome Atlas (TCGA; n = 460) were used to develop a prognostic signature with 23 immune-related gene pairs (23 IRGPs) for CM. Patients were divided into high- and low-risk groups using the TCGA and validation datasets GSE65904 (n = 214), GSE59455 (n = 141), and GSE22153 (n = 79). The ability of the 23-IRGP signature to predict CM was precise, with the stratified high-risk groups showing a poor prognosis, and it had a significant predictive power when used for immune microenvironment and biological analyses. We subsequently established a novel promising prognostic model in CM to determine the association between the immune microenvironment and CM patient results. This approach may be used to discover signatures in other diseases while avoiding the technical biases associated with other platforms.

[A clinical performance study of modified CT angiography in detecting bronchial artery-pulmonary artery fistula]

Objective: To evaluate the clinical value of modified computed tomography angiography(CTA) in detecting bronchial artery-pulmonary artery fistula(BPF). Methods: Retrospective analysis was performed on 246 patients with hemoptysis admitted to the First Affiliated Hospital of Wenzhou Medical University from July 2017 to December 2018, who underwent modified CTA and DSA examination at the same time. CT was performed with Toshiba Aquilion one 320 row 640-slice spiral CT scanner. All modified CTA images were read blindly by two radiologists above the attending doctors. The sensitivity, specificity and accuracy of the modified CTA in diagnosing BPF were calculated with the DSA results as the reference,and the consistency of the two tests was analyzed. Results: DSA detected 186 cases of positive and 60 cases of negative, modified CTA detected 160 cases of positive and 86 cases of negative. The sensitivity,specificity and accuracy of modified CTA for BPF diagnosis was 85.5%(159/186),98.3%(59/60), 88.6%(218/246) respectively, and they were with high consistency with DSA examination results (kappa=0.73,P<0.01). Conclusion: Modified CTA has high diagnostic specificity for BPF,which can be used as the preferred method for non-invasive screening of suspected BPF patients.

A red-emitting Ca8MgLa(PO4)7:Ce3+,Mn2+ phosphor for UV-based white LEDs application

Ca(8)MgLa(PO(4))(7):Ce(3+),Mn(2+) phosphors have been prepared by a conventional solid state reaction under a weak reductive atmosphere. The crystal structure and photoluminescent properties were investigated. It was found that the red emission at 640nm originated from the (4)T(1)((4)G)→(6)A(1)((6)S) transition of Mn(2+) increases dramatically by a factor of 6.4 with the optimum Ce(3+) co-doping. The energy transfer from Ce(3+) to Mn(2+) was proposed to be resonance-type via an electric dipole-dipole mechanism and the energy transfer efficiency was also calculated by the relative emission intensity. With the broadband ultraviolet (UV) absorption of Ce(3+) and the suitable color coordinates, Ca(8)MgLa(PO(4))(7):Ce(3+),Mn(2+) phosphors might be a promising candidate as red phosphors in the field of UV-based white light-emitting diodes.

Enhanced red light emission from LaBSiO5:Eu3+,R3+ (R=Bi or Sm) phosphors

Polycrystalline LaBSiO5:Eu3+,R3+ (R=Bi or Sm) phosphors have been synthesized by a facile sol-gel method. The phosphors have been characterized by thermogravimetric analysis/different scanning calorimeter, scanning electron microscopy, X-ray diffractometer and fluorescence measurements. It was found that the emission intensity of LaBSiO5:Eu phosphors increases clearly and reaches a maximum at 30 mol% with increasing of Eu3+ concentration. The incorporation of Bi3+ ions and/or Sm3+ ions have greatly enhanced the emission intensity of Eu3+ upon excitation with 391 nm light. The possible sensitization mechanisms of Sm3+ and/or Bi3+ on Eu3+ emission intensity have been investigated and discussed. The high brightness and short luminescence decay times make it promising red-emitting candidates for white light-emitting diodes.

White light generation in Eu- and Mn-codoped Ca(7)Mg(2)P(6)O(24) phosphor for white light-emitting diodes

Polycrystalline Ca(7)Mg(2)P(6)O(24):Eu(2+),Mn(2+) phosphors were prepared by a solid-state reaction under a weak reductive atmosphere. The phosphors have been characterized by X-ray diffraction and fluorescence measurements. The results show that the obtained phosphors are of single-phase rhombohedral Ca(7)Mg(2)P(6)O(24). Upon excitation of 355nm ultraviolet (UV) light, two intense broad bands have clearly been observed due to the allowed 5d-4f transition of Eu(2+) and the forbidden (4)T(1)-(6)A(1) transition of Mn(2+), respectively. A white light has been obtained from Ca(7)Mg(2)P(6)O(24):0.035Eu(2+),0.5Mn(2+) phosphor with CIE chromaticity coordinates of (x=0.32, y=0.29) and color temperature of 6175K. These results suggest that Ca(7)Mg(2)P(6)O(24):Eu(2+),Mn(2+) phosphors could be a promising candidate for UV-converting white light-emitting diodes (LEDs).

Bluish-green color emitting Ba2Si3O8:Eu2+ ceramic phosphors for white light-emitting diodes

This paper reports on the structural and optical properties of Eu(2+) activated Ba(2)Si(3)O(8) ceramic phosphors synthesized by a sol-gel method. The ceramic phosphors have been characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and fluorescence measurements. The structural characterization results suggest that the as-prepared phosphors are of single phase monoclinic Ba(2)Si(3)O(8) with rod-like morphology. A broad excitation band ranging from 300 to 410 nm matches well with the ultraviolet (UV) radiation of light-emitting diodes (LEDs). Upon 380 nm UV light excitation, these phosphors emit bluish-green emission centered at 500 nm with color coordination (x=0.25, y=0.40). All the obtained results indicate that the Ba(2)Si(3)O(8):Eu(2+) ceramic phosphors are promising bluish-green candidates for the phosphor-converted white LEDs.

Warm white light from Y4MgSi3O13:Bi3+, Eu3+ nanophosphor for white light-emitting diodes

Y(4)MgSi(3)O(13):Bi(3+), Eu(3+) nanophosphors have been prepared by a facile sol-gel method. The products have been characterized by X-ray diffraction, field-emission scanning electron microscopy and fluorescence measurements. The results show that the nanophosphors are of single phase hexagonal Y(4)MgSi(3)O(13) with size-distribution of 50-90 nm in diameter. White-light emission has been obtained from Bi(3+) and Eu(3+) co-doped Y(4)MgSi(3)O(13) nanophosphors upon excitation of 350 nm ultraviolet light. It is noted that Bi(3+) ions can occupy two different Y(3+) sites and generate different emissions from the (3)p(1) --> (1)s(0) transition. Warm white light has been obtained from Y(4)MgSi(3)O(13):Bi(3+), Eu(3+) nanophosphors according to Commission International de I'Eclairage (CIE) chromaticity coordinates and color temperature (T(c)) with appropriately adjusted contents of Bi(3+) and Eu(3+). The results indicate that Y(4)MgSi(3)O(13):0.08Bi(3+), 0.04Eu(3+) (x = 0.31, y = 0.31, T(c) = 6907 K) are potential nanophosphors for white light-emitting diodes (LEDs) applications.

[Correlation of serum IL-16, IL-18 levels and immunoglobulins in children with asthma]

OBJECTIVE

This study examined the changes of serum levels of interleukin (IL)-16, IL-18 and immunoglobulins and the correlation of serum IL-16, IL-18 levels and immunoglobulins in children with asthma and aimed to explore the role of IL-16, IL-18 and immunoglobulins in the pathogenesis of asthma.

METHODS

Thirty-four children with asthma and 21 age and gender-matched healthy children were enrolled in this study. The levels of IL-16, IL-18 and immunoglobulin E (IgE) were determined using ELISA. Immunoglobulin G (IgG), immunoglobulin M (IgM) and immunoglobulin A (IgA) were detected by immunoturbidimetry.

RESULTS

The levels of IL-16, IL-18 and IgE in patients with asthma at both acute attack and convalescence stages were significantly higher than those in healthy controls. An increased IgG and a decreased IgA levels were found in asthmatic patients at the acute attack stage. There was a positive correlation between the IL-16 and IL-18 levels at both acute attack and convalescence stages of asthma (r=0.70, P < 0.01; r=0.70, P < 0.05). The IL-16 level correlated positively with the IgE level at acute attack stage of asthma (r=0.624, P < 0.01).

CONCLUSIONS

IL-16, IL-18 and IgE may be involved in the pathogenesis of asthma. The immunologic imbalance exists in children with asthma at both acute attack and convalescence stages. Anti-allergic therapy should be administered through the acute attack to the convalescence stages of asthma.

[New type of two-hybrid systems in protein-protein interaction studies]

Some new type of two-hybrid systems, such as split-ubiquitin system, protein-fragment complementation assay, repressor reconstitution assay and SOS recruitment system, have been developed recently. Similar to the original transcription-based yeast two-hybrid system, these systems are to establish an assay for protein-protein interactions, in which some functional proteins can be split into two parts in structure and their activities can be recovered by reconstitution. Due to their non-transcriptional properties, these new types of two-hybrid systems have become useful extension of the yeast two-hybrid system and powerful tools for the study of protein interactions.

Crystal structure of TNF-alpha mutant R31D with greater affinity for receptor R1 compared with R2

Crystal structures have been determined of recombinant human tumor necrosis factor-alpha (TNF-alpha) and its R31D mutant that preferentially binds to TNF receptor R1 with more than seven times the relative affinity of binding to receptor R2. Crystals of the wild-type TNF were of space group P4(1)2(1)2 and had unit cell dimensions of a = b = 94.7 and c = 117.4 A. Refinement of the structure gave an R-factor of 22.3% at 2.5 A resolution. The crystals of TNF R31D mutant diffracted to 2.3 A resolution, and were of identical space group to the wild type with unit cell dimensions of a = b = 95.4 and c = 116.2 A, and the structure was refined to an R-factor of 21.8%. The trimer structures of the wild-type and mutant TNF were similar with a root mean square (r.m.s.) deviation of 0.56 A for Calpha atoms; however, the subunits within each trimer were more variable with an average r.m.s. deviation of 1.00 A on Calpha atoms for pairwise comparison of subunits. Model complexes of TNF with receptors R1 and R2 have been used to predict TNF-receptor interactions. Arg31 in all three subunits of wild-type TNF is predicted to form an ionic interaction with the equivalent glutamic acid in both receptors R1 and R2. Asp31 of the TNF R31D mutant is predicted to interact differently with the two receptors. The side chain of Asp31 in two subunits of the TNF mutant is predicted to form hydrogen bond interactions with Ser59 or Cys70 of R1, while it has no predicted interactions with R2. The loss of three strong ionic interactions of Arg31 and the electrostatic repulsion of Asp31 with Glu in the receptors is consistent with the reduced binding of the R31D mutant to both receptors relative to wild-type TNF. The replacement of these ionic interactions by two weaker hydrogen bond interactions between Asp31 of the R31D mutant and R1, compared with no interactions with R2, is in agreement with the observed preferential binding of the R31D mutant to R1 over R2. Analysis of the structure and function of receptor-discriminating mutants of TNF will help understand the biological role of TNF and facilitate its use as an antitumor agent.

Model complexes of tumor necrosis factor-alpha with receptors R1 and R2

The biological activities of tumor necrosis factor-alpha (TNF-alpha) are mediated by two different receptors, TNFR1 and TNFR2. To analyze the receptor binding site(s) of TNF-alpha, molecular models have been built of the complexes of TNF-alpha with the extracellular regions of receptors R1 and R2, based on the known crystal structures of TNF-alpha and lymphotoxin bound to R1. The model structure of R2 from residues 18-160 was built by analogy to the crystal structure of R1 in complex with lymphotoxin. The amino acid sequences of R1 and R2 show 27.5% identity over this region and were aligned with five insertions and three deletions. There are 18 conserved cysteines that form disulfides. R2 has lost one pair of cysteines compared with R1, but two new cysteines were modeled as forming a new disulfide bond. Both symmetric and asymmetric trimers of TNF-alpha were used to model the complexes with TNFR1 and R2. An analysis of differences in the model complexes showed good agreement with data on the differential binding of TNF mutants to its two receptors.