Detection of Novel BEST1 Variations in Autosomal Recessive Bestrophinopathy Using Third-generation Sequencing

OBJECTIVE

Autosomal recessive bestrophinopathy (ARB), a retinal degenerative disease, is characterized by central visual loss, yellowish multifocal diffuse subretinal deposits, and a dramatic decrease in the light peak on electrooculogram. The potential pathogenic mechanism involves mutations in the BEST1 gene, which encodes Ca2+-activated Cl- channels in the retinal pigment epithelium (RPE), resulting in degeneration of RPE and photoreceptor. In this study, the complete clinical characteristics of two Chinese ARB families were summarized.

METHODS

Pacific Biosciences (PacBio) single-molecule real-time (SMRT) sequencing was performed on the probands to screen for disease-causing gene mutations, and Sanger sequencing was applied to validate variants in the patients and their family members.

RESULTS

Two novel mutations, c.202T>C (chr11:61722628, p.Y68H) and c.867+97G>A, in the BEST1 gene were identified in the two Chinese ARB families. The novel missense mutation BEST1 c.202T>C (p.Y68H) resulted in the substitution of tyrosine with histidine in the N-terminal region of transmembrane domain 2 of bestrophin-1. Another novel variant, BEST1 c.867+97G>A (chr11:61725867), located in intron 7, might be considered a regulatory variant that changes allele-specific binding affinity based on motifs of important transcriptional regulators.

CONCLUSION

Our findings represent the first use of third-generation sequencing (TGS) to identify novel BEST1 mutations in patients with ARB, indicating that TGS can be a more accurate and efficient tool for identifying mutations in specific genes. The novel variants identified further broaden the mutation spectrum of BEST1 in the Chinese population.

ELL associated factor 2 is a potential diagnostic and prognostic indicator: evidence from the in silico and in vitro experiments

Due to the lack of sensitive biomarkers, cancer disease kill 9.6 million individuals each year around the globe. The present study aimed to explore the association between ELL Associated Factor 2 (EAF2) expression and its diagnostic and prognostic landscape across different human cancers using an in silico and in vitro approach. To achieve the defined goals of this study, we used the following online sources: UALCAN, KM plotter, TNMplot, cBioPortal, STRING, DAVID, MuTarget, Cytoscape, and CTD. In addition to this, we also used additional The Cancer Genome Atlas (TCGA) datasets via TIMER2, GENT2, and GEPIA to confirm the expression of EAF2 on additional cohorts. Finally, we performed RNA sequencing (RNA-seq) and targeted bisulfite sequencing (bisulfite-seq) techniques-based analysis using A549, ABC-1, EBC-1, LK-2 lung cancer cell lines, and MRC-9 normal control lung cell line for further validation of the results. On balance, EAF2 was elevated in 19 types of human cancers and its up-regulation was significantly correlated with shorter overall survival (OS), relapse-free survival (RFS), and metastasis in Liver Hepatocellular Carcinoma (LIHC) and Lung Squamous Cell Carcinoma (LUSC) patients. We further evaluated that EAF2 expression was also elevated across LIHC and LUSC patients belonging to different clinicopathological features. Through pathway analysis, EAF2 associations were observed with four important pathways. Moreover, some worth noticing correlations were also documented between EAF2 expression and its promoter methylation level, genetic alterations, other mutant genes, tumor purity, and different immune cells infiltration. The higher EAF2 expression contributes significantly to the tumorigenesis and metastasis of LIHC and LUSC. Therefore, it can be used as a common biomarker in these cancers.

[An analysis of the characteristics of perioperative cardiac troponin elevation in orthopaedic surgical patients]

Objective: Perioperative myocardial infarction remains a severe complication in non-cardiac surgery and is one of the major causes of death. Cardiac troponin (cTn) I elevation is associated with short-term and long-term mortality. The aim of the study was to assess the proportion rate of cTnI elevation and its clinical characteristics among patients admitted for orthopaedic surgery with or without cardiovascular events. Methods: This is a retrospective study including 27 744 patients aged 50 years or older who admitted for orthopaedic surgery from 2009-2015 in Beijing Jishuitan Hospital. Results: Two hundred and sixty-five patients [age (71.7±9.9) years] had cTnI level> 0.04 μg/L with 66% (175 patients) of them being female. Among them, 59 patients were isolated troponin rise (ITR) (n=59), 13 were preoperative acute myocardial infarction (AMI), and 193 were postoperative AMI. The proportion of postoperative AMI was 0.69%. Those patients were more likely to have a history of coronary artery disease or hypertension. Non-ST-segment elevation myocardial infarction (NSTEMI) was more common (93.3%) than ST-segment elevation myocardial infarction in these patients. Most of them did not experience ischemic symptoms. Totally 76.7% of the AMI occurred within 3 days of surgery; and the in-hospital mortality rate was 10.4%. Conclusions: Perioperative elevation of troponin is common in patients undergoing orthopaedic surgery. Most postoperative AMI were NSTEMI and with absent or atypical ischemia symptoms. Monitoring troponin levels and electrocardiograph in at-risk patients is needed to find most of the AMI.

Homology cloning, sequence characterization, and expression analysis of cDNA encoding electron transfer flavoprotein beta polypeptide in mud crab (Scylla paramamosain)

Electron transfer flavoproteins (ETFs) are αβ-heterodimers found in eukaryotic mitochondria and bacteria. Herein we report a full-length complementary DNA of a mud crab (Scylla paramamosain) ETF β subunit (Scpa-ETFB) isolated with a homology cloning strategy. The complete complementary DNA of the Scpa-ETFB contains a 17-nt 5'-untranslated region, a 765-nt open reading frame encoding 254 amino acids, and a 248-nt 3'-untranslated region. The high identity of Scpa-ETFB with ETFB in other organisms indicated that Scpa-ETFB is a new member of the ETFB family. Although the conserved motif associated with flavin adenine dinucleotide binding is absent in Scpa-ETFB, the signature sequences of the ETF superfamily were identified. Using reverse transcriptase polymerase chain reaction, we detected the messenger RNA transcript of Scpa-ETFB in high levels in the tissues of the hepatopancreas, ovary, heart, and muscle. Phylogenetic analysis showed that Scpa-ETFB is most closely related to the ETFB genes of Caligus rogercresseyi and Lepeophtheirus salmonis. These results provided basic information for elucidating the molecular mechanism of energy production in the mud crab.

Characteristic spectrum of very low-energy photoelectron from above-threshold ionization in the tunneling regime

We report an experimental and theoretical study of very low-energy photoelectrons in tunneling ionization process from noble gas atoms interacting with ultrashort intense infrared laser pulses. A universal peak structure with electron energy well below 1 eV in the photoelectron spectrum, corresponding to the double-hump structure in the longitudinal momentum distribution, is identified experimentally for all atomic species. Our quantum and semiclassical analysis reveal the role of long-range Coulomb potential in the production of this very low-energy peak structure.

Development of an enzyme-linked immunosorbent assay for the alpha-cyano pyrethroids multiresidue in Tai lake water

A general and broad class selective competitive enzyme-linked immunosorbent assay (ELISA) for the detection of the alpha-cyano pyrethroids was developed. One class specific hapten, the 5-(3-benzylphenyl)-5-cyanopentanoic acid (CPBA-BE), was conjugated with BSA as an immunogen. Polyclonal antibodies, PY-antibodies, were generated. The assay with the most selectivity for the family alpha-cyano pyrethroids such as cyphenothrin was further optimized and tested for tolerance to cosolvent, pH, and ionic strength changes. The IC(50) values of the optimized immunoassay were 4.58 microg L(-1) for cyphenothrin, 5.62 microg L(-1) for fenpropathrin, 7.08 microg L(-1) for deltamethrin, 10.72 microg L(-1) for cypermethrin, 19.95 microg L(-1) for flucythrinate, and 28.18 microg L(-1) for esfenvalerate. The cross-reactivities of cyphenothrin, fenpropathrin, deltamethrin, cypermethrin, flucythrinate, and esfenvalerate were 100%, 81.49%, 64.68%, 42.72%, 22.96%, and 16.25%, respectively. The low detection limit (LDL) of this assay was 0.107 microg L(-1) for cyphenothrin. This method was used for the detection of the alpha-cyano pyrethroids in Tai lake water.