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Nonketotic hyperglycinemia is an extremely rare autosomal recessively inherited glycine encephalopathy caused by a deficiency in the mitochondrial glycine cleavage system, which leads to severe clinical symptoms. Nonketotic hyperglycinemia is characterized by complex and diverse phenotypes, such as hypotonia, seizures, cognitive impairment, developmental delays and myoclonic jerks that may lead to apnea and even death. Here we report a 1-year-old boy with myoclonic seizures, hypotonia and coma; he had elevated plasma and cerebrospinal fluid glycine levels, and cerebrospinal fluid/plasma glycine ratio was 0.24. Two novel heterozygous mutations confirm the diagnosis of nonketotic hyperglycinemia. One is a missense mutation c.2516A>G (p.Y839C) and the other one is a splicing mutation c.2457+2T>A in the GLDC gene., (Sociedad Argentina de Pediatría.)

The aim of the present study was to compare the diagnostic values of ultrasound micro-flow imaging (SMI) and contrast-enhanced ultrasound (CEUS) for neovascularization in carotid plaques, and to investigate their capacities for predicting the risks of cerebral stroke. A total of 39 patients (64 carotid plaques) with severe carotid artery stenosis undergoing carotid endarterectomy were selected between February 2015 and February 2016, and SMI and CEUS were used to detect neovascularization in plaques. According to the CEUS dynamic graph of plaques, the enhanced intensity visual scales and contrast parameters were obtained. Carotid atherosclerotic plaques were divided into 4 groups. The differences in the enhanced intensity visual scales, contrast parameters, and gray-scale median (GSM) values among the 4 groups were analyzed. Carotid plaque tissue samples from patients were stained for CD34, and the consistency of the methods for the diagnosis of neovascularization in plaques was analyzed. The differences in GSM values, enhanced intensities, and enhanced densities among the 4 groups of plaques were statistically significant (F=29.365, χ 2 =29.025, χ 2 =30.871, P<0.001); the differences in enhanced intensities of carotid atherosclerotic plaques with different echo types were statistically significant (χ 2 =17.951, P<0.001). The enhanced intensity of plaques was negatively correlated with the GSM value (r=-0.376, P<0.01), and the enhanced density of plaques was negatively correlated with the GSM value (r=-0.252, P<0.01). SMI and CEUS grading had good consistency (κ=0.860>0), there were statistically significant differences in new vessel densities with different SMI gradings (P<0.001), and the clinical symptoms and severity were positively correlated with SMI grading (rs=0.592>0). In conclusion, SMI and CEUS have good consistency for evaluating neovascularization in carotid plaques, and have good clinical value for evaluating neovascularization in carotid plaques.

The authors wish to make the following change to their paper [1]. [...].

A novel microfluidic paper-based analytic device (μPAD) biosensor is developed for sensitive and visualized detection of glucose. This biosensor is easily fabricated using the wax printing technique, with a hybrid nanocomplex composed of dual enzymes glucose oxidase (GOx) and horseradish peroxidase (HRP) and Cu 3 (PO 4 ) 2 inorganic nanocrystals incorporated in the detection zones. The hybrid nanocomplex is found to exhibit a flower-like structure, which allows co-immobilization of these two enzymes in a biocompatible environment. These nanoflowers not only preserve the activity and enhance the stability of the enzymes, but also facilitate the transport of the substrates between the two enzymes. The biosensor is demonstrated to enable rapid and sensitive quantification of glucose in the concentration range of 0.1-10 mM with a limit of detection (LOD) of 25 μM. It is also shown to be applicable to colorimetric quantitative detection of glucose in human serum and whole blood samples, implying its potential for clinical applications.

4-Sulfoalkanoic acids are a class of important dianionic-headed surfactants. Various 4-sulfoalkanoic acids with straight C8, C10, C12, C14, C16, and C18 chains were synthesized expeditiously through the radical addition of methyl 2-((ethoxycarbonothioyl)thio)acetate to linear terminal olefins and subsequent oxidation with peroxyformic acid. This is a useful and convenient strategy for the synthesis of dianionic-headed surfactants with a carboxylic acid and sulfonic acid functionalities in the head group region.

Increasing nitrogen oxides (NOx) emissions over the fast developing regions have been of great concern due to their critical associations with the aggravated haze and climate change. However, little geographically specific data exists for estimating spatio-temporal trends of NOx emissions. In order to quantify the spatial and temporal variations of NOx emissions, a spatially explicit approach based on the continuous satellite observations of artificial nighttime stable lights (NSLs) from the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) was developed to estimate NOx emissions from the largest emission source of fossil fuel combustion. The NSL based model was established with three types of data including satellite data of nighttime stable lights, geographical data of administrative boundaries, and provincial energy consumptions in China, where a significant growth of NOx emission has experienced during three policy stages corresponding to the 9th-11th)Five-Year Plan (FYP, 1995-2010). The estimated national NOx emissions increased by 8.2% per year during the study period, and the total annual NOx emissions in China estimated by the NSL-based model were approximately 4.1%-13.8% higher than the previous estimates. The spatio-temporal variations of NOx emissions at city scale were then evaluated by the Moran's I indices. The global Moran's I indices for measuring spatial agglomerations of China's NOx emission increased by 50.7% during 1995-2010. Although the inland cities have shown larger contribution to the emission growth than the more developed coastal cities since 2005, the High-High clusters of NOx emission located in Beijing-Tianjin-Hebei regions, the Yangtze River Delta, and the Pearl River Delta should still be the major focus of NOx mitigation. Our results indicate that the readily available DMSP/OLS nighttime stable lights based model could be an easily accessible and effective tool for achieving strategic decision making toward NOx reduction., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Two-dimensional (2D) layered transition metal dichalcogenides (TMDs) have recently emerged as a new class of atomically thin semiconductors for diverse electronic, optoelectronic, and valleytronic applications. To explore the full potential of these 2D semiconductors requires a precise control of their band gap and electronic properties, which represents a significant challenge in 2D material systems. Here we demonstrate a systematic control of the electronic properties of 2D-TMDs by creating mixed alloys of the intrinsically p-type WSe2 and intrinsically n-type WS2 with variable alloy compositions. We show that a series of WS2xSe2-2x alloy nanosheets can be synthesized with fully tunable chemical compositions and optical properties. Electrical transport studies using back-gated field effect transistors demonstrate that charge carrier types and threshold voltages of the alloy nanosheet transistors can be systematically tuned by adjusting the alloy composition. A highly p-type behavior is observed in selenium-rich alloy, which gradually shifts to lightly p-type, and then switches to lightly n-type characteristics with the increasing sulfur atomic ratio, and eventually evolves into highly n-doped semiconductors in sulfur-rich alloys. The synthesis of WS2xSe2-2x nanosheets with tunable optical and electronic properties represents a critical step toward rational design of 2D electronics with tailored spectral responses and device characteristics.

Cell membrane-anchored biochemical sensors that allow real-time monitoring of the interactions of cells with their microenvironment would be powerful tools for studying the mechanisms underlying various biological processes, such as cell metabolism and signaling. Despite the significance of these techniques, unfortunately, their development has lagged far behind due to the lack of a desirable membrane engineering method. Here, we propose a simple, efficient, biocompatible, and universal strategy for one-step self-construction of cell-surface sensors using diacyllipid-DNA conjugates as the building and sensing elements. The sensors exploit the high membrane-insertion capacity of a diacyllipid tail and good sensing performance of the DNA probes. Based on this strategy, we have engineered specific DNAzymes on the cell membrane for metal ion assay in the extracellular microspace. The immobilized DNAzyme showed excellent performance for reporting and semiquantifying both exogenous and cell-extruded target metal ions in real time. This membrane-anchored sensor could also be used for multiple target detection by having different DNA probes inserted, providing potentially useful tools for versatile applications in cell biology, biomedical research, drug discovery, and tissue engineering.

Background: Relationship between the level of repetitiveness in genomic sequence and genome size has been investigated by making use of complete prokaryotic and eukaryotic genomes, but relevant studies have been rarely made in virus genomes., Results: In this study, a total of 257 viruses were examined, which cover 90% of genera. The results showed that simple sequence repeats (SSRs) is strongly, positively and significantly correlated with genome size. Certain repeat class is distributed in a certain range of genome sequence length. Mono-, di- and tri- repeats are widely distributed in all virus genomes, tetra- SSRs as a common component consist in genomes which more than 100 kb in size; in the range of genome < 100 kb, genomes containing penta- and hexa- SSRs are not more than 50%. Principal components analysis (PCA) indicated that dinucleotide repeat affects the differences of SSRs most strongly among virus genomes. Results showed that SSRs tend to accumulate in larger virus genomes; and the longer genome sequence, the longer repeat units., Conclusions: We conducted this research standing on the height of the whole virus. We concluded that genome size is an important factor in affecting the occurrence of SSRs; hosts are also responsible for the variances of SSRs content to a certain degree.

A highly sensitive and specific colorimetry-based rolling circle amplification (RCA) assay method for single-nucleotide polymorphism genotyping has been developed. A circular template is generated by ligation upon the recognition of a point mutation on DNA targets. An RCA amplification is then initiated using the circular template in the presence of Phi29 polymerase. The RCA product can be digested by a restricting endonuclease, and the cleaved DNA fragments can mediate the aggregation of gold nanoparticle-tagged DNA probes. This causes a colorimetric change of the solution as the indicator of the mutation occurrence, which can be detected using UV-vis spectroscopy or viewed by naked eyes. On the basis of the high amplification efficiency of Phi29 polymerase, a mutated target of approximately 70 fM can be detected in this assay. In addition, the protection of the circle template using phosphorothioated nucleotides allows the digestion reaction to be performed simultaneously in RCA. Moreover, DNA ligase offers high fidelity in distinguishing the mismatched bases at the ligation site, resulting in positive detection of mutant targets even when the ratio of the wild-type to the mutant is 10,000:1. The developed RCA-based colorimetric detection scheme was demonstrated for SNP typing of beta-thalassemia gene at position -28 in genomic DNA.

Combining nanomaterials and biomolecule recognition units is promising in developing novel clinic diagnostic and protein analysis techniques. In this work, a highly sensitive and specific fluorescence resonance energy transfer (FRET) aptasensor for thrombin detection is developed based on the dye labeled aptamer assembled graphene. Due to the noncovalent assembly between aptamer and graphene, fluorescence quenching of the dye takes place because of FRET. The addition of thrombin leads to the fluorescence recovery due to the formation of quadruplex-thrombin complexes which have weak affinity to graphene and keep the dyes away from graphene surface. Because of the high fluorescence quenching efficiency, unique structure, and electronic properties of graphene, the graphene aptasensor exhibits extraordinarily high sensitivity and excellent specificity in both buffer and blood serum. A detection limit as low as 31.3 pM is obtained based on the graphene FRET aptasensor, which is two orders magnitude lower than those of fluorescent sensors based on carbon nanotubes. The excellent performance of FRET aptasensor based on graphene will also be ascribed to the unique structure and electronic properties of graphene.

The present study reports the proof of principle of a reagentless aptameric sensor based on surface-enhanced Raman scattering (SERS) spectroscopy with "signal-on" architecture using a model target of cocaine. This new aptameric sensor is based on the conformational change of the surface-tethered aptamer on a binding target that draws a certain Raman reporter in close proximity to the SERS substrate, thereby increasing the Raman scattering signal due to the local enhancement effect of SERS. To improve the response performance, the sensor is fabricated from a cocaine-templated mixed self-assembly of a 3'-terminal tetramethylrhodamine (TMR)-labeled DNA aptamer on a silver colloid film by means of an alkanethiol moiety at the 5' end. This immobilization strategy optimizes the orientation of the aptamer on the surface and facilitates the folding on the binding target. Under optimized assay conditions, one can determine cocaine at a concentration of 1 muM, which compares favorably with analogous aptameric sensors based on electrochemical and fluorescence techniques. The sensor can be readily regenerated by being washed with a buffer. These results suggest that the SERS-based transducer might create a new dimension for future development of aptameric sensors for sensitive determination in biochemical and biomedical studies.

Determining the rank of a trilinear data array is a first step in subsequent trilinear component decomposition. Different from estimating the rank of bilinear data, it is more difficult to decide the significant number of component to fit the trilinear decompositions exactly. General methods of rank estimation utilize the information contained in the singular values but ignore information from eigenvectors. In this paper, a rank estimating method specifically for trilinear data arrays is proposed. It uses the idea of direct trilinear decomposition (DTLD) to compress the cube matrix into two pseudo sample matrices which are then decomposed by singular value decomposition. Two eigenvectors combined with the projection technique are used to estimate the rank of trilinear data arrays. Simulated trilinear data arrays with homoscedastic and heteroscedastic noise, different noise levels, high collinearity, and real three-way data arrays have been used to illustrate the feasibility of the proposed method. Compared with other factor-determining methods, for example use of the factor indication function (IND), residual percentage variance (RPV), and the two-mode subspace comparison approach (TMSC), the results showed that the new method can give more reliable answers under the different conditions applied.

Molecular recognition sites for mercury ions were imprinted in TiO(2) film using stable ground-state complex of 1-amino-8-naphtol-3,6-disodium sulfonate (ANDS) and mercury ions as template. The complex ratio between mercury ions and ANDS was estimated to be 2:1. Compared with the controlled and pure TiO(2) electrodes, the imprinted electrode revealed selectivity towards the imprinted ions. Linear calibration plots for mercury ions were obtained and the regression equation was I(p) (muA)=4.29x10(-7)+19.40 [Hg(2+)] with a detection limit of 3.06x10(-9)mol/l. The imprinted electrode could be used for more than 1 month. Recoveries were calculated at both high and low concentrations, with a mean recovery of 99.6%.

A multicenter cooperative investigated the incidence of Phenylketonuria (PKU) in the central, southern and western areas of Guangdong province and its surrounding districts. Tests to measure phenylalanine (Phe) on dried blood spots on filter paper cards used BIA and thefluorescence assay. Four hundred sixty-one thousand eight hundred five (461,805) newborns were screened and 14 cases of persistent hyperphenylalaninemia (PHPA) were detected. The incidence of PHPA was 1/33,000, including 1/77,000 for classical PKU; 1 in 66,000 for hyperphenylalaninemia (HPA) and 1 in 461,805 for BH4 deficiency. A high variation in PKU incidence in the different districts was observed. The differences may be attributed to the variations in gene frequency of PKU in the different districts and to bioethical consideration especially as regards reproduction in different areas.

To establish the neonatal screening method of glucose-6 phosphate dehydrogenase (G6PD) deficiency, G6PD activity was measured using the fluorescence spot test (FST) using dried blood samples on filter paper. The G6PD/6PGD rate test of venous blood samples was further performed for confirmation. The positive G6PD deficiency rate was 4.2% and its detection rates were 3.7% for all neonates and 5.2% only for male newborns when FST was used for neonatal screening. Conformation rates by use of G6PD/ 6PGD ratio test for G6PD deficiency were 86.8% and 100% particularly in the severely deficient groups. Both sensitivity and specificity were very high in the severely deficient groups. FST can be used in neonatal screening of G6PD deficiency because of its high accuracy, applicability, and simplicity. Moreover, a high volume of dried blood samples on filter paper can be tested quickly. It is very favorable to diagnose and treat G6PD deficiency early in high incidence districts.