Analytical and clinical performance evaluation of a new NT-proBNP assay.

BACKGROUND: The study evaluated the performance of the Mindray N-terminal pro-B-type natriuretic peptide (NT-proBNP) in a healthy population in China, focusing on creating a reference range for future clinical applications adjusted according to different demographics. METHODS: The study measured NT-proBNP in 2277 healthy individuals. We analyzed age and sex-stratified data, performed precision, accuracy, linearitcvy, and detection limit studies, and evaluated method comparison and consistency between Roche and Mindray assays on 724 serum samples. We used Excel 2010, Medcalc, and GraphPad Prism 9. RESULTS: In males, the 97.5th centile NT-proBNP concentration at age < 45, 45 to 54, 55 to 64, 65 to 74 and ≧ 75 were 89.4 ng/L, 126 ng/L, 206 ng/L, 386 ng/L and 522 ng/L, respectively. In females, the concentration of NT-proBNP at the same age was 132 ng/L, 229 ng/L, 262 ng/L, 297 ng/L and 807 ng/L, respectively. The repeatability precision coefficient of variation (CV%) for NT-proBNP was between 0.86 and 1.65 in analytical performance. In contrast, the reproducibility precision (CV%) for NT-proBNP was between 1.52 and 3.22, respectively. The study found a bias of accuracy of 3.73% in low-value samples (concentration: 148.69) and 7.31% in high-value samples (concentration: 1939.08). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 125 ng/L were 96.6%, 92.3%, 84.2%, and 98.5%, respectively. In contrast, those of 300 ng/L were 94.0%, 98.2%, 95.7% and 97.5%, respectively. CONCLUSIONS: The Mindray NT-proBNP assay showed increased levels in both males and females with age, with higher levels in women. It performs well and aligns with manufacturer specifications. We recommend adjusting cutoff values based on demographic factors.

ß-Cryptoxanthin Maintains Mitochondrial Function by Promoting NRF2 Nuclear Translocation to Inhibit Oxidative Stress-Induced Senescence in HK-2 Cells.

The mechanisms of acute kidney injury and chronic kidney disease remain incompletely revealed, and drug development is a pressing clinical challenge. Oxidative stress-induced cellular senescence and mitochondrial damage are important biological events in a variety of kidney diseases. As a type of carotenoid, ß-Cryptoxanthin (BCX) has various biological functions, which means it is a potential therapeutic candidate for the treatment of kidney disease. However, the role of BCX in the kidney is unclear, and the effect of BCX on oxidative stress and cellular senescence in renal cells is also unknown. Therefore, we conducted a series of studies on human renal tubular epithelial (HK-2) cells in vitro. In the present study, we investigated the effect of BCX pretreatment on H2O2-induced oxidative stress and cellular senescence and explored the potential mechanism of BCX action. The results showed that BCX attenuated H2O2-induced oxidative stress and cellular senescence in HK-2 cells. Moreover, BCX promoted NRF2 nuclear expression, maintained mitochondrial function, and reduced mitochondrial damage in HK-2 cells. In addition, silencing NRF2 altered the protective effect of BCX on mitochondria and significantly reversed the anti-oxidative stress and anti-senescence effects of BCX in HK-2 cells. We concluded that BCX maintained mitochondrial function by promoting NRF2 nuclear translocation to inhibit oxidative stress-induced senescence in HK-2 cells. In light of these findings, the application of BCX might be a promising strategy for the prevention and treatment of kidney diseases.

Lysine-specific demethylase 1 aggravated oxidative stress and ferroptosis induced by renal ischemia and reperfusion injury through activation of TLR4/NOX4 pathway in mice.

Acute kidney injury (AKI) is mainly caused by renal ischaemia reperfusion injury (IRI). Lots of evidence suggests that ferroptosis and oxidative stress play the vital role in renal IRI. However, the specific mechanism of renal IRI has not been fully elucidated. lysine-specific demethylase 1 (LSD1) has been shown to regulate the pathogenesis of kidney disease. In this study, we firstly found that LSD1 was positively related to renal IRI. TCP, a classical LSD1 inhibitor, could alleviate tissue damage induced by renal IRI. Inhibition of LSD1 with either TCP or LSD1 knockdown could alleviate ferroptosis and oxidative stress caused by IRI both in vivo and in vitro. Furthermore, the results showed that suppression of LSD1 decreased the expression of TLR4/NOX4 pathway in HK-2 cells subjected to H/R. With the si-RNA against TLR4 or NOX4, it showed that the silence of TLR4/NOX4 reduced oxidative stress and ferroptosis in vitro. Moreover, to demonstrate the crucial role of TLR4/NOX4, TLR4 reduction, mediated by inhibition of LSD1, was compensated through delivering the adenovirus carrying TLR4 in vitro. The results showed that the compensation of TLR4 blunted the alleviation of oxidative stress and ferroptosis, induced by LSD1 inhibition. Further study showed that LSD1 activates TLR4/NOX4 pathway by reducing the enrichment of H3K9me2 in the TLR4 promoter region. In conclusion, our results demonstrated that LSD1 inhibition blocked ferroptosis and oxidative stress caused by renal IRI through the TLR4/NOX4 pathway, indicating that LSD1 could be a potential therapeutic target for renal IRI.

Epidemiological and clinical characteristics of respiratory viruses in 4403 pediatric patients from multiple hospitals in Guangdong, China.

BACKGROUND: Acute respiratory infections (ARI) cause considerable morbidity and mortality worldwide, especially in children. Unfortunately, there are limited multi-center data on common viral respiratory infections in south China. METHODS: A total of 4403 nasal swabs were collected from children in 10 cities in Guangdong, China in 2019. Seven respiratory viruses, influenza A virus (IFA), influenza B virus (IFB), respiratory syncytial virus (RSV), adenoviruses (ADV) and parainfluenza virus types 1-3 (PIV1, PIV2 and PIV3), were detected by direct immunofluorescence antibody assay. The personal information and clinical characteristics were recorded and analyzed. RESULTS: The results showed that at least one virus was detected in 1099 (24.96 %) samples. The detection rates of RSV, IFA, ADV, PIV3, PIV1 and PIV2 were 7.13 % (314/4403), 5.31 % (234/4403), 4.02 % (177/4403), 3.04 % (134/4403), 1.70 % (75/4403) and 1.16 % (51/4403), respectively. The detection rate of RSV was highest in 0-6-month-old children at 18.18 % (106/583), while the detection rate of IFA was highest in 12-18-year-old children at 20.48 % (17/83). The total detection rates in winter and spring were 35.67 % (219/614) and 34.56 % (403/1166), higher than those in summer, 17.41 % (284/1631), and autumn, 19.46 % (193/992). CONCLUSIONS: RSV and IFA were the main respiratory viruses in children. With increasing age the detection rate of RSV decreased in children, but the trends for the detection rates of IFA and IFB were the opposite. This study provided the viral etiology and epidemiology of pediatric patients with ARI in Guangdong, China.

Fluorescence-Quenching Lateral Flow Immunoassay for "Turn-On" and Sensitive Detection of Anti-SARS-Cov-2 Neutralizing Antibodies in Human Serum.

The titer of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibodies (NAbs) in the human body is an essential reference for evaluating the acquired protective immunity and resistance to SARS-CoV-2 infection. In this study, a fluorescence-quenching lateral flow immunoassay (FQ-LFIA) is established for quantitative detection of anti-SARS-CoV-2 NAbs in the sera of individuals who are vaccinated or infected within 10 min. The ultrabright aggregation-induced emission properties encapsulated in nanoparticles, AIE490 NP, are applied in the established FQ-LFIA with gold nanoparticles to achieve a fluorescence "turn-on" competitive immunoassay. Under optimized conditions, the FQ-LFIA quantitatively detected 103 positive and 50 negative human serum samples with a limit of detection (LoD) of 1.29 IU mL-1 . A strong correlation is present with the conventional pseudovirus-based virus neutralization test (R2  = 0.9796, P < 0.0001). In contrast, the traditional LFIA with a "turn-off" mode can only achieve a LoD of 11.06 IU mL-1 . The FQ-LFIA showed excellent sensitivity to anti-SARS-CoV-2 NAbs. The intra- and inter-assay precisions of the established method are below 15%. The established FQ-LFIA has promising potential as a rapid and quantitative method for detecting anti-SARS-CoV-2 NAbs. FQ-LFIA can also be used to detect various biomarkers.

Optimization of a Ge2Sb2Te5-Based Electrically Tunable Phase-Change Thermal Emitter for Dynamic Thermal Camouflage.

Controlling infrared thermal radiations can significantly improve the environmental adaptability of targets and has attracted increasing attention in the field of thermal camouflage. Thermal emitters based on Ge2Sb2Te5 (GST) can flexibly change their radiation energy by controlling the reversible phase transition of GST, which possesses fast switching speed and low power consumption. However, the feasibility of the dynamic regulation of GST emitters lacks experimental and simulation verification. In this paper, we propose an electrically tunable thermal emitter consisting of a metal-insulator-metal plasmonic metasurface based on GST. Both optical and thermal simulations are conducted to optimize the structural parameters of the GST emitter. The results indicate that this emitter possesses large emissivity tunability, wide incident angle, polarization insensitivity, phase-transition feasibility, and dynamic thermal camouflage capability. Therefore, this work proposes a reliable optimization method to design viable GST-based thermal emitters. Moreover, it provides theoretical support for the practical application of phase-change materials in dynamic infrared thermal camouflage technology.

Synthesis of functional carbon nanospheres by a composite-molten-salt method and amperometric sensing of hydrogen peroxide.

Functional carbon nanospheres have been synthesized from analytically pure glucose by a composite-molten-salt (CMS) method. Field emission scanning electron microscopy, transmission electron microscopy, Raman and Fourier transformation infra-red spectroscopy indicate the carbon nanospheres are solid, bond hybridisation (sp2/sp3) and with many functional groups on their surfaces. Amperometric sensor based on the synthesized carbon nanospheres have been fabricated without pretreatment or modification. The detection of hydrogen peroxide exhibits high sensitivity and good selectivity. The electrochemical measurement of these nanospheres demonstrates much superior performance to those of the carbon nanospheres synthesized by hydrothermal method.

Puerarin alleviated oxidative stress and ferroptosis during renal fibrosis induced by ischemia/reperfusion injury via TLR4/Nox4 pathway in rats.

PURPOSE: To investigate the role of puerarin on renal fibrosis and the underlying mechanism in renal ischemia and reperfusion (I/R) model. METHODS: Rats were intraperitoneally injected with puerarin (50 or 100 mg/kg) per day for one week before renal I/R. The level of renal collagen deposition and interstitial fibrosis were observed by hematoxylin and eosin and Sirius Red staining, and the expression of α-smooth muscle actin (α-SMA) was examined by immunohistochemical staining. The ferroptosis related factors and TLR4/Nox4-pathway-associated proteins were detected by Western blotting. RESULTS: Puerarin was observed to alleviate renal collagen deposition, interstitial fibrosis and the α-SMA expression induced by I/R. Superoxide dismutase (SOD) activities and glutathione (GSH) level were decreased in I/R and hypoxia/reoxygenation (H/R), whereas malondialdehyde (MDA) and Fe2+ level increased. However, puerarin reversed SOD, MDA, GSH and Fe2+ level changes induced by I/R and H/R. Besides, Western blot indicated that puerarin inhibited the expression of ferroptosis related factors in a dose-dependent manner, which further demonstrated that puerarin had the effect to attenuate ferroptosis. Moreover, the increased expression of TLR/Nox4-pathway-associated proteins were observed in I/R and H/R group, but puerarin alleviated the elevated TLR/Nox4 expression. CONCLUSIONS: Our results suggested that puerarin inhibited oxidative stress and ferroptosis induced by I/R and, thus, delayed the progression of renal fibrosis, providing a new target for the treatment of renal fibrosis.

Cyanidin-3-O-glucoside plays a protective role against renal ischemia/ reperfusion injury via the JAK/STAT pathway.

PURPOSE: To investigate the role of cyanidin-3-O-glucoside (C3G) in renal ischemia/reperfusion (I/R) injury and the potential mechanisms. METHODS: Mouse models were established by clamping the left renal vessels, and in vitro cellular models were established by hypoxic reoxygenation. RESULTS: Renal dysfunction and tissue structural damage were significantly higher in the I/R group. After treatment with different concentrations of C3G, the levels of renal dysfunction and tissue structural damage decreased at different levels. And its protective effect was most pronounced at 200 mg/kg. The use of C3G reduced apoptosis as well as the expression of endoplasmic reticulum stress (ERS)-related proteins. Hypoxia/reoxygenation (H/R)-induced apoptosis and ERS are dependent on oxidative stress in vitro. In addition, both AG490 and C3G inhibited the activation of JAK/STAT pathway and attenuated oxidative stress, ischemia-induced apoptosis and ERS. CONCLUSIONS: The results demonstrated that C3G blocked renal apoptosis and ERS protein expression by preventing reactive oxygen species (ROS) production after I/R via the JAK/STAT pathway, suggesting that C3G may be a potential therapeutic agent for renal I/R injury.

Fucoxanthin Attenuates Oxidative Damage by Activating the Sirt1/Nrf2/HO-1 Signaling Pathway to Protect the Kidney from Ischemia-Reperfusion Injury.

Oxidative stress is a key component of renal ischemia/reperfusion (I/R) injury. Fucoxanthin (Fx), a marine carotenoid with enhanced antioxidant capacity, acts as a ROS inhibitor in diseases such as ischemic stroke and acute lung injury. We hypothesized that fucoxanthin could attenuate renal I/R-induced oxidative damage. C57BL/6 mice (n = 30) were randomly assigned to sham, IR, IR + DMSO, and IR + Fx (25, 50, and 100 mg/kg) groups. The renal I/R injury was induced by clamping the left kidney nephron tip in mice. Fucoxanthin was injected intraperitoneally 24 hours before surgery. Compared with the IR group, pretreatment with fucoxanthin significantly improved renal dysfunction and tissue structural damage and inhibited ROS levels and apoptosis. Consistent results were observed in HK-2 cells. Besides, we found that renal I/R resulted in decreased expression of Sirt1, Nrf2, and HO-1, while fucoxanthin upregulated the expression of Sirt1, Nrf2, and HO-1. The protective effects of fucoxanthin were significantly reversed by EX527 (a selective inhibitor of Sirt1) or si-Sirt1. In conclusion, our study investigated the protective effect of fucoxanthin against renal I/R injury, and the underlying mechanism may be related to the activation of the Sirt1/Nrf2/HO-1 signaling pathway by fucoxanthin to attenuate oxidative stress-induced apoptosis.

The LINC01929/miR-6875-5p/ADAMTS12 Axis in the ceRNA Network Regulates the Development of Advanced Bladder Cancer.

Considering its speedy development and extremely low 5-year overall survival rate worldwide, bladder cancer (BCa) is one of the most common and highly malignant tumors. Increasing evidence suggests that protein-coding mRNAs and non-coding RNAs, including long non-coding RNAs (lncRNAs) and micro RNAs (miRNAs), play an essential role in regulating the biological processes of cancer. To investigate the molecular regulation associated with poor prognosis during advanced BCa development, we constructed a competitive endogenous RNA (ceRNA) network. Using transcriptome profiles from The Cancer Genome Atlas and Gene Expression Omnibus databases, we performed differential expression (DE) analysis, weighted gene co-expression network analysis, functional enrichment analysis, survival analysis, prediction of miRNA targeting, and Pearson correlation analysis. Through layers of selection, 8 lncRNAs-28 mRNAs and 8 miRNAs-28 mRNAs pairs shared similar expression patterns, constituting a core ceRNA regulatory network related to the invasion, progression, and metastasis of advanced clinical stage (ACS) BCa. Subsequently, we conducted real time qPCR, western blotting, and immunohistochemistry to validate expression trend bioinformatics analysis on 3, 2, and 3 differentially expressed mRNAs, lncRNAs, and miRNAs, respectively. The most significantly differentially expressed LINC01929, miR-6875-5p and ADAMTS12 were selected for in vitro experiments to assess the functional role of the LINC01929/miR-6875-5p/ADAMTS12 axis. RNA pull-down, luciferase assays, and rescue assays were performed to examine the binding of LINC01929 and miR-6875-5p. Increasing trends in COL6A1, CDH11, ADAMTS12, LINC01705, and LINC01929 expression variation were verified as consistent with previous DE analysis results in ACS-BCa, compared with low clinical stage (LCS) BCa. Expression trends in parts of these RNAs, such as hsa-miR-6875-5p, hsa-miR-6784-5p, COL6A1, and CDH11, were measured in accordance with DE analysis in LCS-BCa, compared with normal bladder urothelium. Through experimental validation, the cancer-promoting molecule ADAMST12 was found to play a key role in the development of advanced BCa. Functionally, ADAMTS12 knockdown inhibited the progression of bladder cancer. Overexpression of LINC01929 promoted bladder cancer development, while overexpression of miR-6785-5p inhibited bladder cancer development. Mechanistically, LINC01929 acted as a sponge for miR-6785-5p and partially reversed the role of miR-6785-5p. Our findings provide an elucidation of the molecular mechanism by which advanced bladder cancer highly expressed LINC01929 upregulates ADAMTS12 expression through competitive adsorption of miR-6875-5p. It provides a new target for the prognosis and diagnosis of advanced bladder cancer.

Mitochondria-Targeted Antioxidant Mitoquinone Maintains Mitochondrial Homeostasis through the Sirt3-Dependent Pathway to Mitigate Oxidative Damage Caused by Renal Ischemia/Reperfusion.

Mitochondrial dysfunction is a critical factor contributing to oxidative stress and apoptosis in ischemia-reperfusion (I/R) diseases. Mitoquinone (MitoQ) is a mitochondria-targeted antioxidant whose potent anti-I/R injury capacity has been demonstrated in organs such as the heart and the intestine. In the present study, we explored the role of MitoQ in maintaining mitochondrial homeostasis and attenuating oxidative damage in renal I/R injury. We discovered that the decreased renal function and pathological damage caused by renal I/R injury were significantly ameliorated by MitoQ. MitoQ markedly reversed mitochondrial damage after I/R injury and inhibited renal reactive oxygen species production. In vitro, hypoxia/reoxygenation resulted in increased mitochondrial fission and decreased mitochondrial fusion in human renal tubular epithelial cells (HK-2), which were partially prevented by MitoQ. MitoQ treatment inhibited oxidative stress and reduced apoptosis in HK-2 cells by restoring mitochondrial membrane potential, promoting ATP production, and facilitating mitochondrial fusion. Deeply, renal I/R injury led to a decreased expression of sirtuin-3 (Sirt3), which was recovered by MitoQ. Moreover, the inhibition of Sirt3 partially eliminated the protective effect of MitoQ on mitochondria and increased oxidative damage. Overall, our data demonstrate a mitochondrial protective effect of MitoQ, which raises the possibility of MitoQ as a novel therapy for renal I/R.

Europium (III) chelate nanoparticle-based lateral flow immunoassay strips for rapid and quantitative detection of cystatin C in serum.

The concentration of Cys C in the patient's serum can reflect the level of glomerular filtration rate and indicate the occurrence of renal failure. The establishment of a simple and rapid analytical method to quantitatively monitor the concentration of Cys C in serum could help timely detection of renal failure. In this study, we have developed an Eu (III) chelate nanoparticles based lateral flow immunoassay to fulfill real-time monitoring of Cys C concentration in serum within 15 min. This method was performed as a sandwich immunoassay with a wide detection range (0.05-10 µg/mL) and a low limit of detection (24.54 ng/mL). The intra and inter-assay coefficients of variation were 8.31-8.61% and 8.92-9.95%, respectively. Furthermore, the application of this method was evaluated by comparing the determined results with those obtained by chemiluminescence immunoassay, exhibiting a satisfactory correlation (R2 = 0.9830). The developed LFIA method with satisfactory analytical performance has great potential for real-time monitoring of renal failure and self-detection for the high-risk population.

A deep learning-based system for assessment of serum quality using sample images.

BACKGROUND: Serum quality is an important factor in the pre-analytical phase of laboratory analysis. Visual inspection of serum quality (including recognition of hemolysis, icterus, and lipemia) is widely used in clinical laboratories but is time-consuming, subjective, and prone to errors. METHODS: Deep learning models were trained using a dataset of 16,427 centrifuged blood images with known serum indices values (including hemolytic index, icteric index, and lipemic index) and their performance was evaluated by five-fold cross-validation. Models were developed for recognizing qualified, unqualified and image-interfered samples, predicting serum indices values, and finally composed into a deep learning-based system for the automatic assessment of serum quality. RESULTS: The area under the receiver operating characteristic curve (AUC) of the developed model for recognizing qualified, unqualified and image-interfered samples was 0.987, 0.983, and 0.999 respectively. As for subclassification of hemolysis, icterus, and lipemia, the AUCs were 0.989, 0.996, and 0.993. For serum indices and total bilirubin predictions, the Pearson's correlation coefficients (PCCs) of the developed model were 0.840, 0.963, 0.854, and 0.953 respectively. Moreover, 30.8% of serum indices tests were deemed unnecessary due to the preliminary application of the deep learning-based system. CONCLUSIONS: The deep learning-based system is suitable for the assessment of serum quality and holds the potential to be used as an accurate, efficient, and rarely interfered solution in clinical laboratories.

The spectrum of FVIII gene variants detected by next generation sequencing in 236 Chinese non-inversion hemophilia A pedigrees.

INTRODUCTION: The reported variants of hemophilia A are mainly from European subjects and American subjects of European descent, and limited data are available from more diverse ethnic backgrounds. This study was performed to identify the causative variants in a large HA cohort from Chinese population. MATERIALS AND METHODS: A total of 236 HA pedigrees were included. Molecular analysis of F8 gene was performed using next-generation sequencing (NGS) and then validated by Sanger sequencing and multiplex ligation probe amplification (MLPA) results. Variants were classified as pathogenic, likely pathogenic, variant of unknown significance, likely benign, and benign according to the American College of Medical Genetics and Genomics guidelines. RESULTS: A total of 186 F8 variants were identified, with 139 (139/186, 74.73%) point mutations, 44 (44/186, 23.66%) small insertions/deletions (InDels), and 3 (3/186, 1.61%) large deletions, they included 80 pathogenic and 84 likely pathogenic variants. Of these variants, 119 had been reported previously, and 67 were novel. No potentially causative mutations were found in the targeted F8 region in seventeen HA pedigrees. CONCLUSIONS: The spectrum of F8 variants identified in this study provides additional information about HA and enriches our knowledge of the variant spectrum in a wider range of ethnic backgrounds.

Rapid visual detection of dengue virus by combining reverse transcription recombinase-aided amplification with lateral-flow dipstick assay.

OBJECTIVES: Dengue caused by infection with the dengue virus (DENV) is endemic in the tropical and subtropical regions of the world and of greatest public health concern. With more large outbreaks in rural areas, the purpose of this study was to develop a point-of-care test using recombinase-aided amplification and lateral-flow dipsticks for rapidly detecting DENV in low-resource settings. METHODS: The primers for the recombinase-aided amplification (RAA) assay were designed based on 3' UTR of the DENV genome and screened. The RAA temperature, time and the concentration of primers were then optimized, as well as the lateral-flow dipstick assay (LFD) time. Finally, the diagnostic performance of the reverse transcription (RT)-RAA-LFD assay was evaluated using blood samples from 247 patients who were clinically suspected to be infected with DENV. RESULTS: The RAA primer pair F1/R2 was the optimal combination for detecting DENV. The RT-RAA was performed in an incubator block at 37°C for 20minutes, and the amplicons were visible in the flow dipsticks from a naked eye within 3minutes. The detection limit of the developed RT-RAA-LFD assay was 10 copies/µL with high specificity for DENV. Compared with commercial reverse transcription quantitative PCR assay, the kappa value of RT-RAA-LFD in the 247 clinical samples was 0.957. CONCLUSIONS: In this study, a rapid and visual point-of-care test based on RT-RAA and LFD assay was developed. It was found to be suitable for reliable detection of DENV in low-resource settings with limited laboratory capabilities and optimal storage conditions.

Molecular analysis of 76 Chinese hemophilia B pedigrees and the identification of 10 novel mutations.

BACKGROUND: Hemophilia B (HB) is an X-linked recessive inherited bleeding disorder caused by mutations in the F9 gene that lead to plasma factor IX deficiency. To identify the causative mutations in HB, a molecular analysis of HB pedigrees in China was performed. METHODS: Using next-generation sequencing (NGS) and an in-house bioinformatics pipeline, 76 unrelated HB pedigrees were analyzed. The mutations identified were validated by comparison with the results of Sanger sequencing or Multiplex Ligation-dependent Probe Amplification assays. The pathogenicity of the causative mutations was classified following the American College of Medical Genetics and Genomics guidelines. RESULTS: The mutation detection rate was 94.74% (72/76) using NGS. Of the 76 HB pedigrees analyzed, 59 causative variants were found in 72 pedigrees, with 38 (64.41%) missense mutations, 9 (15.25%) nonsense mutations, 2 (3.39%) splicing mutations, 5 (8.47%) small deletions, 4 (6.78%) large deletions, and 1 intronic mutation (1.69%). Of the 59 different F9 mutations, 10 were novel: c.190T>G, c.199G>T, c.290G>C, c.322T>A, c.350_351insACAATAATTCCTA, c.391+5delG, c.416G>T, c.618_627delAGCTGAAACC, c.863delA, and c.1024_1027delACGA. Of these 10 novel mutations, a mosaic mutation, c.199G>T(p.Glu67Ter), was identified in a sporadic HB pedigree. Using in-silico analysis, these novel variants were predicted to be disease-causing. However, no potentially causative mutations were found in the F9 coding sequences of the four remaining HB pedigrees. In addition, two HB pedigrees carrying additional F8/F9 mutations were discovered. CONCLUSION: The identification of these mutations enriches the spectrum of F9 mutations and provides further insights into the pathogenesis of HB in the Chinese population.

Different Clinical Phenotypes Caused by Three F8 Missense Mutations in Three Chinese Families with Moderate Hemophilia A.

In families with a monogenic disorder, the causal mutation usually cosegregates with the disease phenotype. In rare cases, however, individuals carrying the same mutation within a family may show various phenotypes. This study aimed to analyze the discrepancy between genotype and phenotype in three families with moderate hemophilia A (HA) caused by missense mutation in the F8 gene. Among the 67 noninversion moderate HA families in our cohort, incomplete penetrance was found in three families. In these three families, the grandfathers were asymptomatic, whereas the probands had different clinical phenotypes. Apart from one mutation in the VWF gene (c.1330 G>A) found in one grandfather, only one missense mutation (c.5837A>T, c.6679G>A, and c.6506G>A, in the respective families) in the F8 gene was identified in each proband and their grandfathers. Subsequent Sanger sequencing results combined with bioinformatic analysis indicated that the three missense mutations in the F8 gene were the causative mutations. Our study demonstrated incomplete penetrance of missense mutation within HA families in China. Therefore, genetic counseling and management of such cases need to be reappraised.

Combination of iterated cubature Kalman filter and neural networks for GPS/INS during GPS outages.

To improve the performance of the Global Positioning System/Inertial Navigation System (GPS/INS) integrated navigation system, current research studies merely combine neural networks with nonlinear filter methods. Few studies focus on how to optimize the parameters of the neural network and how to further improve the small error accumulated into the next filter step due to the imprecise design of the filter when setting the initial parameters in the GPS/INS integrated system. In this article, a dual optimization method consisting of an iterated cubature Kalman filter-Feedforward Neural Network (ICKF-FNN) and a radial basis function-cubature Kalman filter (RBF-CKF) is proposed to compensate the position and velocity errors of the integrated system during GPS outages. The prominent advantages of the proposed method include the following. (i) The ICKF is designed to optimize the parameters of the introduced FNN adaptively and obtain an appropriate internal structure when GPS is available, which improves the accuracy of the training model. (ii) The RBF establishes the relationship between filter parameters and the optimal estimation errors, reducing the errors caused by inaccurate predicted observation during GPS outages. (iii) The proposed dual optimization method takes advantages over other combination algorithms under different moving conditions or even during long period of GPS outages, which shows its great stability. Experimental results show that the root mean squared error of the east position is reduced by 85.79% to 3.2187 m using the proposed strategy during turning movement and the east velocity error accumulation rate decreases by 92.69% during the long straight movement of 250 s. These results are from offline processing.