The comprehensive study on the role of POSTN in fetal congenital heart disease and clinical applications.

BACKGROUND: Congenital heart defect (CHD) is the most common congenital abnormality, and it has long been a clinical and public health concern. Our previous findings have found Periostin (POSTN) and Pappalysin-1 (PAPPA) as potential biomarkers for fetal CHD. We aim to further elucidate POSTN's role in fetal heart development and explore the clinical applicability of POSTN and PAPPA as diagnostic marker for fetal CHD. This study is poised to establish a theoretical framework for mitigating the incidence of CHD and advance a novel approach for prenatal screening of fetal CHD. METHODS: We verified differential expression of POSTN and PAPPA in gravida serum and fetal amniotic fluid based on our previous research. We established the Postn knockout mouse by CRISPR/Cas9 to investigate whether Postn deletion leads to cardiac abnormalities in mice. Besides, we explored the mechanism of POSTN on heart development through Postn knockout mouse model and cell experiments. Finally, we established the logistic regression model and decision curve analysis to evaluate the clinical utility of POSTN and PAPPA in fetal CHD. RESULTS: We observed a significant decrease in POSTN and increase in PAPPA in the CHD group. Atrial septal defects occurred in Postn-/- and Postn± C57BL/6 fetal heart, while ventricular septal defects with aortic saddle were observed in Postn± C57BL/6 fetal heart. Disruption of the extracellular matrix (ECM) in cardiomyocytes and multiple abnormalities in cellular sub-organelles were observed in Postn knockout mice. POSTN may positively regulate cell behaviors and unsettle ECM via the TGFß-Smad2/3 signaling pathway. The combination of serum biomarkers POSTN and PAPPA with Echocardiogram can enhance the diagnostic accuracy of CHD. Furthermore, the comprehensive model including POSTN, PAPPA, and two clinical indicators (NT and age) exhibits significantly higher predictive ability than the diagnosis group without the use of serum biomarkers or clinical indicators. CONCLUSIONS: It is the first evidence that Postn deletion leads to cardiac developmental abnormalities in fetal mice. This may involve the regulation of the TGFß signaling pathway. Importantly, POSTN and PAPPA possess clinical utility as noninvasive prenatal promising screening indicators of CHD.

Reduced Graphene Oxide Nanosheets Decorated with Copper and Silver Nanoparticles for Achieving Superior Strength and Ductility in Titanium Composites.

Graphene and its derivates are extensively applied to enhance the mechanical properties of metal matrix nanocomposites. However, their high reactivity with a metal matrix such as titanium and thus the limited strengthening effects are major problems for achieving high-performance graphene-based nanocomposites. Herein, reduced graphene oxide nanosheets decorated with copper or silver (i.e., Cu@rGO and Ag@rGO) nanopowders are introduced into Ti matrix composites using multiple processes of one-step chemical coreduction, hydrothermal synthesis, low-energy ball milling, spark plasma sintering, and hot rolling. The Cu@rGO/Ti and Ag@rGO/Ti nanocomposites exhibit significantly enhanced strength with superior elongation to fracture (846 MPa-11.6 and 900 MPa-8.4%, respectively, basically reaching the level of the commercial Ti-6Al-4V titanium alloy), which are much higher than those of the fabricated Ti (670 MPa-7.0%) and rGO/Ti composites (726 MPa-11.3%). Furthermore, fracture toughness values of the M@rGO/Ti composites are all significantly improved, that is, the highest KIC value is 34.4 MPa·m1/2 for 0.5Cu@rGO/Ti composites, which is 20.28 and 51.5% higher than those of monolithic Ti and 0.5rGO/Ti composites, respectively. The outstanding mechanical properties of Ag@rGO/Ti and Cu@rGO/Ti composites are attributed to the effective load transfer of in situ formed TiC nanoparticles and the formation of interfacial intermetallic compounds between the rGO nanosheets and Ti matrix. This study provides new insights and approach for the fabrication of metal-modified graphene/Ti composites with a high performance.

Closed bipolar electrode based fluorescence visualization biosensor for anti-interference detection of T-2 toxin.

A closed bipolar electrode (BPE) based fluorescence visualization biosensor was successfully constructed and used for anti-interference detection of T-2 toxin.

[Research progress on the biological properties of the surface nanocrystals of typical medical metal materials].

Biomedical metal materials have always been a major biomedical material with a large and wide range of clinical use due to their excellent properties such as high strength and toughness, fatigue resistance, easy forming, and corrosion resistance. They are also the preferred implant material for hard tissues (bones and teeth that need to withstand higher loads) and interventional stents. And nano-medical metal materials have better corrosion resistance and biocompatibility. This article focuses on the changes and improvements in the properties of several typical medical metal materials surfaces after nanocrystallization, and discusses the current problems and development prospects of nano-medical metal materials.

Clinical outcomes of prenatal diagnosis of the fetal micrognathia: A case report.

RATIONALE: Micrognathia is a subtle facial malformation characterized by a small mandible and receding chin. Fetal micrognathia is often associated with chromosomal abnormalities, skeletal dysplasia, and various syndromes. Once it is dignosised, detailed fetal malformation screening and chromosome examination should be carried out. PATIENT CONCERN: One pregnant woman with suspicion of fetal micrognathia was referred from her local hospital to our hospital for detailed fetal malformation screening and fetal echocardiography. Examination of the fetus was performed using a two-dimensional and three-dimensional ultrasound probe in multiple planes. The fetus showed micrognathia without glossoptosis with features of the inferior facial angle (IFA) ≤50° and his tongue reached anterior mandibular border box during normal movement. DIAGNOSES: The fetus was diagnosed as isolated micrognathia prenatally without multisystem abnormalities. INTERVENTIONS: Amniocentesis was performed and the fetus was found to carry 46XN with 6q14.1 duplication, the significance of which was unclear. OUTCOMES: The fetus was labored through vagina at 38 weeks gestation. A small soft cleft palate was diagnosed after delivery. LESSONS: This case suggests that once prenatal diagnosis of the fetal micrognathia has been made, we should carefully examine the presence of fetus's multisystem developmental abnormalities and due consideration should be given for associated soft cleft palate.

Highly active metal-free peroxidase mimics based on oxygen-doped carbon nitride by promoting electron transfer capacity.

A heteroatom oxygen doping strategy was developed to prepare oxygen-doped carbon nitride (OCN). The performance and mechanism of its peroxidase-like activity were studied for the first time. The greatly improved peroxidase-like activity could be attributed to the promoted electron transferability.

Electrochemical Corrosion Behavior and Mechanical Properties of Nanocrystalline Ti⁻6Al⁻4V Alloy Induced by Sliding Friction Treatment.

A nanograined (NG) layer with an average grain size of less than 100 nm has been successfully prepared on a Ti⁻6Al⁻4V sheet surface by sliding friction treatment (SFT). The electrochemical corrosion/passive behavior and mechanical properties of an NG Ti⁻6Al⁻4V sheet were examined in this study. A bi-layer passive film that consisted of an outer TiO2-rich layer and an inner Al2O3-rich layer was formed on either an NG or coarse-grained (CG) surface. The improved corrosion was mainly caused by the enhanced stability and thickness of the passive layer. Tensile experiments were carried out to evaluate the mechanical properties at ambient temperature. The NG Ti⁻6Al⁻4V sample exhibited the high yield strength (956 MPa) with a moderate elongation of 8%. These superior comprehensive properties demonstrated its potential as a biomedical material.

A universal photoelectrochemical biosensor for dual microRNA detection based on two CdTe nanocomposites.

Various diseases are closely related to simultaneous changes of multiple miRNAs expression levels. It's of great significance to develop photoelectrochemical (PEC) biosensors for multiple miRNA detection for both clinical diagnosis and biological mechanisms research. In this work we designed a novel PEC biosensor for simultaneous dual miRNA detection for the first time. Two nanocomposites, CdTe loaded carbon nitride nanosheets (CdTe-C3N4) with an anodic photocurrent and CdTe loaded 3D graphene hydrogel (CdTe-3DGH) with a cathodic photocurrent were prepared and showed enhanced PEC performances. Photocurrents of the two nanocomposites can be clearly distinguished at the corresponding critical voltages. Then probe DNA1 and DNA2 were combined with CdTe-3DGH and CdTe-C3N4 NCs through covalent bonding respectively. With the competitive hybridization reaction between target miRNAs and the complementary DNA (cDNA), concentrations of miRNA141 and miRNA21 may be sensitively quantified by the respective photocurrent change. Compared with traditional PEC biosensors, this design didn't require any additional equipment and can provide a higher detection efficiency, which has a good universality and expansibility for the fabrication of multiplex PEC assays.

A Sunlight Powered Portable Photoelectrochemical Biosensor Based on a Potentiometric Resolve Ratiometric Principle.

As a new analysis tool, photoelectrochemical (PEC) biosensors have been widely studied in recent years. However, common PEC biosensors usually require a highly stable light source to excite the electrical signal and an electrochemical workstation to collect and process the signal data, which limited the development of portable PEC devices. Herein, we propose the design of a sunlight powered portable PEC biosensor that uses sunlight as the light source. The sunlight intensity changes over time and weather and results in varied background PEC currents. To eliminate the interference caused by unstable excitation light, the potentiometric resolve ratiometric principle was introduced. Coupled with a miniature electrochemical workstation and a laptop, a sensitive and portable PEC sensing platform was successfully developed. The detection may be achieved under the irradiation of sunlight and will no longer need an extra light source. In a proof of concept experiment, this platform was successfully applied in aflatoxin B1 analysis, which was promising in the development of portable biosensors.

A pH-Resolved Colorimetric Biosensor for Simultaneous Multiple Target Detection.

Colorimetric detection has been widely applied in daily life. However, on the other hand, the further development of colorimetric biosensors has been constrained by the lack of multiple detection capabilities. In this work, we proposed a pH-resolved colorimetric biosensor for the first time for the simultaneous detection of four targets, including ochratoxin A (OTA), aflatoxins B1 (AFB1), fumonisin B1 (FB1), and microcystin-LR (MC-LR). With allochroic dyes as the signal indicators, pH value was introduced as the new dimension to control the release of dyes. The concentrations of four targets can be obtained in order by adjusting the pH of the solution. Meanwhile, tedious and high-cost chemical modification processes in the fabrications of biosensors were also avoided by the combination of DNA-directed self-assembly of graphene oxide and magnetic separation. This biosensor provided a simple, rapid, accurate, and low-cost strategy for multiple target detection.

A sensitive Potentiometric resolved ratiometric Photoelectrochemical aptasensor for Escherichia coli detection fabricated with non-metallic nanomaterials.

In this work, a sensitive potentiometric resolved ratiometric photoelectrochemical aptasensor for Escherichia coli (E. coli) detection was successfully fabricated with non-metallic nanomaterials. To avoid the use of precious metals or heavy metals, three-dimensional graphene hydrogel-loaded carbon quantum dots (C-dots/3DGH) and graphene-like carbon nitride (g-C3N4) with excellent PEC activity and matched potential were prepared. These two materials were modified onto two adjacent areas on the ITO electrode. By applying different bias voltage, the cathodic current generated by C-dots/3DGH and the anodic current generated by g-C3N4 can be clearly distinguished and would not interfere with one another. Then E. coli aptamer was modified onto the surface of C-dots/3DGH. In the presence of targets, the binding of E. coli with aptamer lead to the steric hindrance greatly increased and the cathodic current decreased significantly. Meanwhile, the anodic current generated by g-C3N4 was not influenced and it can serve as a stable reference to evaluate the environmental factors. Therefore, the concentration of E. coli can be quantified by the ratio of cathodic current to anodic current, which can effectively eliminate these analyte-independent factors and provide a more precise analysis. In addition, this ratiometric PEC biosensor also showed a good sensitivity and a wide linear range (2.9 cfu/mL to 2.9 × 106 cfu/mL).

Prognosis of 591 fetuses with ultrasonic soft markers during mid-term pregnancy.

The present study aimed to examine the value of ultrasonic soft markers in prenatal screening by analyzing the clinical outcome of fetuses with ultrasonic soft markers during the second trimester of pregnancy. A retrospective analysis was performed to evaluate the outcome of 591 fetuses with ultrasonic soft markers from January 2015 to August 2016 in Zhongnan Hospital of Wuhan University, China. It was found that 591 fetuses showed ultrasonic soft markers in 4927 cases with the occurrence rate being 12.0%. Among them, 564 fetuses (95.4%) were delivered and the remaining 27 cases (4.6%) were aborted. Five hundred and sixty-seven cases had single ultrasonic soft marker, including echogenic intracardiac focus (n=343), mild renal pelvis dilatation (n=116), short long bones (n=72), single umbilical artery (n=31), mild lateral ventriculomegaly (n=21), choroid plexus cysts (n=19), and echogenic bowel (n=13), with the disappearing rates in pregnancy being 97.1% (333/343), 77.6% (90/116), 0% (0/72), 0% (0/31), 57.1% (12/21), 89.5% (17/19) and 61.5% (8/13) respectively. The rate of pregnancy termination due to single ultrasonic soft marker was 3.4% (19/567), and that was 33.3% (8/24) due to two ultrasonic soft markers with the difference being statistically significant (P<0.05). The reasons of pregnancy termination included malformations (polycystic kidney, cleft lip and palate, congenital heart diseases, pcromphalus, hypospadias, hydrocephalus), chromosome abnormality, and stillbirth. It was concluded that single ultrasonic soft marker is usually transient manifestation in pregnancy. Without the other structural defects, single ultrasonic soft marker usually disappears spontaneously with favorable prognosis in a low-risk population. It is suggested that ultrasonic soft markers should be appropriately interpreted to avoid unnecessary invasive examination.

Electrochemical corrosion behavior and elasticity properties of Ti-6Al-xFe alloys for biomedical applications.

The present study is to investigate the microstructural characteristics, electrochemical corrosion behavior and elasticity properties of Ti-6Al-xFe alloys with Fe addition for biomedical application, and Ti-6Al-4V alloy with two-phase (α+ß) microstructure is also studied as a comparison. Microstructural characterization reveals that the phase and crystal structure are sensitive to the Fe content. Ti-6Al alloy displays feather-like hexagonal α phase, and Ti-6Al-1Fe exhibits coarse lath structure of hexagonal α phase and a small amount of ß phase. Ti-6Al-2Fe and Ti-6Al-4Fe alloys are dominated by elongated, equiaxed α phase and retained ß phase, but the size of α phase particle in Ti-6Al-4Fe alloy is much smaller than that in Ti-6Al-2Fe alloy. The corrosion resistance of these alloys is determined in SBF solution at 37 °C. It is found that the alloys spontaneously form a passive oxide film on their surface after immersion for 500 s, and then they are stable for polarizations up to 0 VSCE. In comparison with Ti-6Al and Ti-6Al-4V alloys, Ti-6Al-xFe alloys exhibit better corrosion resistance with lower anodic current densities, larger polarization resistances and higher open-circuit potentials. The passive layers show stable characteristics, and the wide frequency ranges displaying capacitive characteristics occur for high iron contents. Elasticity experiments are performed to evaluate the elasticity property at room temperature. Ti-6Al-4Fe alloy has the lowest Young's modulus (112 GPa) and exhibits the highest strength/modulus ratios as large as 8.6, which is similar to that of c.p. Ti (8.5). These characteristics of Ti-6Al-xFe alloys form the basis of a great potential to be used as biomedical implantation materials.