Hypermethylation of the Bmp4 promoter dampens binding of HIF-1α and impairs its cardiac protective effects from oxidative stress in prenatally GC-exposed offspring.

The exposure to an unhealthy environment in utero can lead to the occurrence of cardiovascular diseases in the offspring. Glucocorticoids (GC) are essential for normal development and maturation of fetal organs and is a first-line treatment for pregnant women affected by autoimmune diseases. However, excess prenatal GC exposure might program the development of fetal organs and cause a number of chronic diseases in later life. Our previous studies indicated that cardiac functions were significantly compromised in rat offspring prenatally exposed to the synthetic glucocorticoid dexamethasone (DEX), only after ischemia-reperfusion. In the present study, we further observed that DNA hypermethylation of bone morphogenetic protein 4 (Bmp4) promoter in cardiomyocytes caused by prenatal DEX exposure substantially dampened the binding activity of transcription factor HIF-1α induced by cardiac ischemia. Therefore, prenatal DEX exposure inhibits the induction of BMP4 upon I/R and attenuates the protective effects of BMP4 in cardiomyocytes, which eventually manifests as malfunction of the adult heart. Moreover, we employed two cardiac-specific Bmp4 knock-in mouse models and found that in vivo BMP4 overexpression could rescue the cardiac dysfunction caused by prenatal GC exposure. In depth mechanistic research revealed that BMP4 protects the cardiomyocytes from mitophagy and apoptosis by attenuating mitochondrial PGC-1α expression in a p-Smad and Parkin-dependent manner. These findings suggest that prenatal GC exposure increases the susceptibility of the offspring's heart to a "second strike" after birth, due to the failure of hypoxia-induced HIF-1α transactivation of the hypermethylated Bmp4 promoter in cardiomyocytes. Pretreatment with the DNA methylation inhibitor, 5-Aza-2'-deoxycytidine, could be a potential therapeutic method for this programming effect of GC exposure during pregnancy on neonatal cardiac dysfunction.

Development of a general separation strategy by countercurrent chromatography using sanshools from Zanthoxylum bungeanum oleoresin as a case study.

Three kinds of sanshools were separated from Zanthoxylum bungeanum oleoresin by high-speed countercurrent chromatography. Sanshools are a series of amide compounds extracted from the Zanthoxylum bungeanum. Due to similar structures, polarities, and dissociation constants, it was challenging to select an appropriate solvent system for their complete separation by countercurrent chromatography. To address this challenge, a solvent-system-selection strategy was proposed to identify a relatively suitable solvent system. Additionally, a separation procedure incorporating multi-elution modes selection was established to separate similar compounds in a logical order. Ultimately, a solvent system comprising n-hexane:ethyl acetate:methanol:water in a ratio of 19:1:1:5.67 was selected. Three amide compounds with high purity were obtained through the use of recycling elution mode to improve separation resolution: hydroxy-ε-sanshool (8.4 mg; purity: 90.64%), hydroxy-α-sanshool (326.4 mg; purity: 98.96%), and hydroxy-ß-sanshool (71.8 mg; purity: 98.26%) were obtained from 600 mg sanshool crude extract. The summarized solvent-system-selection strategy and separation procedure incorporating multi-elution modes may instruct countercurrent chromatography users, particularly novices, seeking to separate compounds with highly similar chemical properties.

High-speed interferometric imaging reveals dynamics of neuronal deformation during the action potential.

Neurons undergo nanometer-scale deformations during action potentials, and the underlying mechanism has been actively debated for decades. Previous observations were limited to a single spot or the cell boundary, while movement across the entire neuron during the action potential remained unclear. Here we report full-field imaging of cellular deformations accompanying the action potential in mammalian neuron somas (-1.8 to 1.4 nm) and neurites (-0.7 to 0.9 nm), using high-speed quantitative phase imaging with a temporal resolution of 0.1 ms and an optical path length sensitivity of <4 pm per pixel. The spike-triggered average, synchronized to electrical recording, demonstrates that the time course of the optical phase changes closely matches the dynamics of the electrical signal. Utilizing the spatial and temporal correlations of the phase signals across the cell, we enhance the detection and segmentation of spiking cells compared to the shot-noise-limited performance of single pixels. Using three-dimensional (3D) cellular morphology extracted via confocal microscopy, we demonstrate that the voltage-dependent changes in the membrane tension induced by ionic repulsion can explain the magnitude, time course, and spatial features of the phase imaging. Our full-field observations of the spike-induced deformations shed light upon the electromechanical coupling mechanism in electrogenic cells and open the door to noninvasive label-free imaging of neural signaling.

High Sensitivity and Wide Linearity LC-MS/MS Method for Oxylipin Quantification in Multiple Biological Samples.

Oxylipins are important biological regulators that have received extensive research attention. Due to the extremely low concentrations, large concentration variations, and high structural similarity of many oxylipins, the quantitative analysis of oxylipins in biological samples is always a great challenge. Here, we developed a liquid chromatography-tandem mass spectrometry-based method with high sensitivity, wide linearity, and acceptable resolution for quantitative profiling of oxylipins in multiple biological samples. A total of 104 oxylipins, some with a high risk of detection crosstalk, were well separated on a 150 mm column over 20 min. The method showed high sensitivity with lower limits of quantitation for 87 oxylipins, reaching 0.05-0.5 pg. Unexpectedly, we found that the linear range for 16, 18, and 17 oxylipins reached 10,000, 20,000, and 40,000 folds, respectively. Due to the high sensitivity, while reducing sample consumption to below half the volume of previous methods, 74, 78, and 59 low-abundance oxylipins, among which some were difficult to detect like lipoxins and resolvins, were well quantified in the tested mouse plasma, mouse liver, and human plasma samples, respectively. Additionally, we determined that analytes with multifarious concentrations of over a 1,000-fold difference could be well quantified simultaneously due to the wide linearity. In conclusion, most likely due to the instrumental advancement, this method effectively improves the quantitative sensitivity and linear range over existing methods, which will facilitate and advance the study of the physiological and pathophysiological functions of oxylipins.

New application of an old drug proparacaine in treating epilepsy via liposomal hydrogel formulation.

Proparacaine (PPC) is a previously discovered topical anesthetic for ophthalmic optometry and surgery by blocking the central Nav1.3. In this study, we found that proparacaine hydrochloride (PPC-HCl) exerted an acute robust antiepileptic effect in pilocarpine-induced epilepsy mice. More importantly, chronic treatment with PPC-HCl totally terminated spontaneous recurrent seizure occurrence without significant toxicity. Chronic treatment with PPC-HCl did not cause obvious cytotoxicity, neuropsychiatric adverse effects, hepatotoxicity, cardiotoxicity, and even genotoxicity that evaluated by whole genome-scale transcriptomic analyses. Only when in a high dose (50 mg/kg), the QRS interval measured by electrocardiography was slightly prolonged, which was similar to the impact of levetiracetam. Nevertheless, to overcome this potential issue, we adopt a liposome encapsulation strategy that could alleviate cardiotoxicity and prepared a type of hydrogel containing PPC-HCl for sustained release. Implantation of thermosensitive chitosan-based hydrogel containing liposomal PPC-HCl into the subcutaneous tissue exerted immediate and long-lasting remission from spontaneous recurrent seizure in epileptic mice without affecting QRS interval. Therefore, this new liposomal hydrogel formulation of proparacaine could be developed as a transdermal patch for treating epilepsy, avoiding the severe toxicity after chronic treatment with current antiepileptic drugs in clinic.

Interferometric mapping of material properties using thermal perturbation.

Optical phase changes induced by transient perturbations provide a sensitive measure of material properties. We demonstrate the high sensitivity and speed of such methods, using two interferometric techniques: quantitative phase imaging (QPI) in transmission and phase-resolved optical coherence tomography (OCT) in reflection. Shot-noise-limited QPI can resolve energy deposition of about 3.4 mJ/cm2 in a single pulse, which corresponds to 0.8 °C temperature rise in a single cell. OCT can detect deposition of 24 mJ/cm2 energy between two scattering interfaces producing signals with about 30-dB signal-to-noise ratio (SNR), and 4.7 mJ/cm2 when SNR is 45 dB. Both techniques can image thermal changes within the thermal confinement time, which enables accurate single-shot mapping of absorption coefficients even in highly scattering samples, as well as electrical conductivity and many other material properties in biological samples at cellular scale. Integration of the phase changes along the beam path helps increase sensitivity, and the signal relaxation time reveals the size of hidden objects. These methods may enable multiple applications, ranging from temperature-controlled retinal laser therapy or gene expression to mapping electric current density and characterization of semiconductor devices with rapid pump-probe measurements.

Mixed Transcriptome Analysis Revealed the Possible Interaction Mechanisms between Zizania latifolia and Ustilago esculenta Inducing Jiaobai Stem-Gall Formation.

The smut fungus Ustilago esculenta infects Zizania latifolia and induces stem expansion to form a unique vegetable named Jiaobai. Although previous studies have demonstrated that hormonal control is essential for triggering stem swelling, the role of hormones synthesized by Z. latifolia and U. esculenta and the underlying molecular mechanism are not yet clear. To study the mechanism that triggers swollen stem formation, we analyzed the gene expression pattern of both interacting organisms during the initial trigger of culm gall formation, at which time the infective hyphae also propagated extensively and penetrated host stem cells. Transcriptional analysis indicated that abundant genes involving fungal pathogenicity and plant resistance were reprogrammed to maintain the subtle balance between the parasite and host. In addition, the expression of genes involved in auxin biosynthesis of U. esculenta obviously decreased during stem swelling, while a large number of genes related to the synthesis, metabolism and signal transduction of hormones of the host plant were stimulated and showed specific expression patterns, particularly, the expression of ZlYUCCA9 (a flavin monooxygenase, the key enzyme in indole-3-acetic acid (IAA) biosynthesis pathway) increased significantly. Simultaneously, the content of IAA increased significantly, while the contents of cytokinin and gibberellin showed the opposite trend. We speculated that auxin produced by the host plant, rather than the fungus, triggers stem swelling. Furthermore, from the differently expressed genes, two candidate Cys2-His2 (C2H2) zinc finger proteins, GME3058_g and GME5963_g, were identified from U. esculenta, which may conduct fungus growth and infection at the initial stage of stem-gall formation.

[Placental mechanisms underlying the effects of maternal stress on the fetal development].

Placenta is the only link between the pregnant woman and fetus, and the basis for maintaining the normal pregnancy process and fetal development. Maternal stress is the maternal physiological and psychological changes caused by various factors, characterized by the increased level of glucocorticoid, which affects the hypothalamic-pituitary-target gland axis and regulates the expression of target genes. Maternal stress also changes the weight, metabolism and nutrient transportation of the placenta, which will substantially influence the development of fetus. This paper will firstly summarize the characteristics of maternal stress and its influence on offspring. Then, the changes in the body under maternal stress will be described. Finally, we will clarify the proven mechanisms underlying maternal stress and raise some important problems that have not been clarified in this area. The study of maternal stress on fetus and its underlying mechanisms will serve as theoretical basis for the diagnosis and treatment of the stress-related pregnant diseases and disorders.

Decrease in SHP-1 enhances myometrium remodeling via FAK activation leading to labor.

Preterm birth is one of the most common complications during human pregnancy and is associated with a dramatic switch within the uterus from quiescence to contractility. However, the mechanisms underlying uterine remodeling are largely unknown. Protein kinases and phosphatases play critical roles in regulating the phosphorylation of proteins involved in the smooth muscle cell functions. In the present study, we found that Src-homology phosphatase type-1 (SHP-1, PTPN6) was significantly decreased in human myometrium in labor compared with that not in labor. Timed-pregnant mice injected intraperitoneally with the specific SHP-1 inhibitor protein tyrosine phosphatase inhibitor I (PTPI-1) manifested significantly preterm labor, with enriched plasmalemmal dense plaques between myometrial cells and increased phosphorylation at Tyr397 and Tyr576/577 sites of focal adhesion kinase (FAK) in myometrial cells, which remained to the time of labor, whereas the phosphorylation levels of ERK1/2 and phosphatidylinositol 3 kinase (PI3K) showed a rapid increase upon PTPI-1 injection but fell back to normal at the time of labor. The Tyr576/577 in FAK played an important role in the interaction between FAK and SHP-1. Knockdown of SHP-1 dramatically increased the spontaneous contraction of human uterine smooth muscle cells (HUSMCs), which was reversed by coinfection of a FAK-knockdown lentivirus. PGF2α downregulated SHP-1 via PLCß-PKC-NF-κB or PI3K-NF-κB pathways, suggesting the regenerative downregulation of SHP-1 enhances the uterine remodeling and plasticity by activating FAK and subsequent focal adhesion pathway, which eventually facilitates myometrium contraction and leads to labor. The study sheds new light on understanding of mechanisms that underlie the initiation of labor, and interventions for modulation of SHP-1 may provide a potential strategy for preventing preterm birth.

Sinusoidal Single-Pixel Imaging Based on Fourier Positive-Negative Intensity Correlation.

Single-pixel imaging techniques extend the time dimension to reconstruct a target scene in the spatial domain based on single-pixel detectors. Structured light illumination modulates the target scene by utilizing multi-pattern projection, and the reflected or transmitted light is measured by a single-pixel detector as total intensity. To reduce the imaging time and capture high-quality images with a single-pixel imaging technique, orthogonal patterns have been used instead of random patterns in recent years. The most representative among them are Hadamard patterns and Fourier sinusoidal patterns. Here, we present an alternative Fourier single-pixel imaging technique that can reconstruct high-quality images with an intensity correlation algorithm using acquired Fourier positive-negative images. We use the Fourier matrix to generate sinusoidal and phase-shifting sinusoid-modulated structural illumination patterns, which correspond to Fourier negative imaging and positive imaging, respectively. The proposed technique can obtain two centrosymmetric images in the intermediate imaging course. A high-quality image is reconstructed by applying intensity correlation to the negative and positive images for phase compensation. We performed simulations and experiments, which obtained high-quality images, demonstrating the feasibility of the methods. The proposed technique has the potential to image under sub-sampling conditions.

First report of black-heart disease in Kumamoto oyster Crassostrea sikamea spat caused by Polydora lingshuiensis in China.

A black-heart disease caused by polydorid infestation is reported for the first time in Kumamoto oyster Crassostrea sikamea Amemiya, 1928 spat in a pond at Beihai city, Guangxi province, China, with a prevalence of 100% and a cumulative mortality rate of 50% within 2 mo. In heavily infected oyster spat, blisters extended toward the center of the inner shell surface, around the adductor muscle scar area to form a large black area occupying approximately 50% of the area of the inner shell surface. Morphological analysis identified the pathogen as Polydora lingshuiensis Ye et al., 2015, which was reconfirmed by comparison of its corresponding 18S rRNA and mitochondrial CO1 gene sequences with those in the GenBank database. The mean abundance of mud blisters was significantly higher in live spat than in dead spat, suggesting that P. lingshuiensis preferentially infests live oyster spat. Additionally, P. lingshuiensis larvae were detected in the inlet near the dam, which suggests that the source of P. lingshuiensis larvae infecting the spat may be larvae entering the ponds through the water current from the sea.

[Effect of Guben Zenggu Decoction on Expressions of Serum BALP and CaM, CaMKâ ¡ mRNA in NEI Network of Ovariectomized Rats].

OBJECTIVE: To observe the effect of Guben Zenggu Decoction on the expressions of calmodulin (CaM) and calcium/calmodulin-dependent protein kinase Ⅱ (CaMK Ⅱ) mRNA in the hypothalamus, pituitary, spleen, adrenal gland and femur in ovariectomized rats. To explore the mechanism of Guben Zenggu Decoction regulating and controlling osteoporosis through neuro-endocrine-immune (NEI) network. METHODS: The osteoporosis model was established by ovariectomy and randomly divided into model control group, Estradiol valerate group, Guben Zenggu Decoction high, medium and low concentration group. Selected the same age rats as the blank control group, after intervention, 10 rats were randomly selected at the time of 4th, 8th, 12th and 16th weeks from each group, After the success of the model and the successful intervention of Guben Zenggu Decoction for 4, 8, 12 and 16 weeks, the blood were taken from the heart, the serum bone alkaline phosphatase (BALP) levels was measured by the enzyme-linked immunosorbent assay (ELISA), and the thalamus, pituitary, spleen, adrenal, femoral tissue of rats were collected to detected the expressions of CaM and CaMKⅡ mRNA by using real-time fluorescence quantitative polymerase chain reaction (RT-PCR). RESULTS: At different time points (4 weeks, 8 weeks, 12 weeks, 16 weeks), the expressions of serum BALP and CaM and CaMKⅡ mRNA in NEI network in model group were significantly different from those in blank control group ( P<0.05). Compared with the model control group, serum BALP concentration and CaM mRNA expression in hypothalamus and pituitary tissue were significantly increased in estradiol valerate and Guben Zenggu Decoction groups ( P<0.05). However, the expression of CaM mRNA in adrenal gland, spleen and femur and the expression of CaMKⅡ mRNA in hypothalamus, pituitary, adrenal gland, spleen and femur were significantly decreased ( P<0.05); compared with estradiol valerate group, the effect of Guben Zenggu Decoction on the expressions of CaM mRNA and CaMKⅡ mRNA in femoral and adrenal tissues was significantly different ( P<0.05). CONCLUSION: Guben Zenggu Decoction can increase the serum concentration of BALP, regulate the expression of CaM mRNA and CaMKⅡ mRNA in hypothalamus, pituitary, adrenal gland, spleen and femur, thus play a role in prevention and treatment of osteoporosis by regulating NEI network.

High-precision calibration method for shear ratio based on the shearing wavefront feature extraction of a phase plate.

A new method based on the shearing wavefront feature extraction (SWFE) of a phase plate is proposed to accurately estimate the shear ratio of the system. The relationship between the shear ratio of a quadriwave lateral shearing interferometer based on a randomly encoded hybrid grating (REHG) and the measurement sensitivity, dynamic range, and wavefront retrieval accuracy is analyzed to provide a theoretical guidance for practical application. The simulation result of the SWFE method shows that the relative error of the shear ratio value is about 1.8×10-3, within the acceptable range of the system. In the experiment, two fused quartz phase plates etched with step change edge grooves were introduced to calibrate the shear ratio of the REHG wavefront diagnosis system. Then, the etching depths of these two phase plates and the figure error of a spherical surface were characterized by the REHG. A comparison with a ZYGO GPI interferometer exhibits that the testing results by the REHG are highly precise, which further confirms the effectiveness of the SWFE method in the shear ratio calibration. This shear ratio calibration method is available for similar kind of shearing interferometric wavefront sensor.

Biological and immunological characterization of norovirus major capsid proteins from three different genotypes.

Noroviruses (NoVs) are the leading cause of non-bacterial acute gastroenteritis worldwide. Due to a lack of cell culture system and animal model, our understanding of NoVs has been lagging behind. In this study, NoV major capsid proteins (VP1) from three different genotypes (GI.2, GII.3 and GII.4) were expressed by using recombinant baculovirus expression system and which led to successful assembly of virus-like particles (VLPs). The receptor binding patterns of three kinds of VLPs were characterized by using synthetic and salivary HBGA-VLP binding assay. Cross-reactivity and cross-blocking activity of rabbit hyperimmune sera against these VLPs were determined by ELISA/Western blot analysis and saliva-VLP binding blockade assay, respectively. Expression of the major capsid proteins from three genotypes all led to smaller VLPs in dominance when sf9 cells were cultured in suspension, which was in consistence with our previous report. These smaller VLPs were used for in vitro synthetic and salivary HBGA-VLP binding and binding blockade assays. VLPs from GII.3 strain exhibited no binding to all synthetic HBGAs and saliva samples tested while VLPs from GI.2 and GII.4 strain showed similar binding pattern and bound to all salivary HBGAs tested. Rabbit anti-GII.3 VLPs hyperimmune serum didn't block the binding of GI.2 and GII.4 VLPs to salivary HBGAs while rabbit anti-GI.2 VLP hyperimmune serum blocked the binding of GII.4 VLPs to salivary HBGAs but not vice versa. Our results provide further evidence indirectly in support of presence of other factors involved in receptor binding other than HBGAs for NoVs, and demonstrate poor cross-blocking activities of antibodies against VLPs within or across genogroups.

Practical phase unwrapping of interferometric fringes based on unscented Kalman filter technique.

A phase unwrapping algorithm for interferometric fringes based on the unscented Kalman filter (UKF) technique is proposed. The algorithm can bring about accurate phase unwrapping and good noise suppression simultaneously by incorporating the true phase and its derivative in the state vector estimation through the UKF process. Simulations indicate that the proposed algorithm has better accuracy than some widely employed phase unwrapping approaches in the same noise condition. Also, the time consumption of the algorithm is reasonably acceptable. Applications of the algorithm in our different optical interferometer systems are provided to demonstrate its practicability with good performance. We hope this algorithm can be a practical approach that can help to reduce the systematic errors significantly induced by phase unwrapping process for interferometric measurements such as wavefront distortion testing, surface figure testing of optics, etc.

Quadriwave lateral shearing interferometer based on a randomly encoded hybrid grating.

A compact quadriwave lateral shearing interferometer (QWLSI) with strong adaptability and high precision is proposed based on a novel randomly encoded hybrid grating (REHG). By performing the inverse Fourier transform of the desired ±1 Fraunhofer diffraction orders, the amplitude and phase distributions of the ideally calculated quadriwave grating can be obtained. Then a phase chessboard is introduced to generate the same phase distribution, while the amplitude distribution can be achieved using the randomly encoding method by quantizing the radiant flux on the ideal quadriwave grating. As the Faunhofer diffraction of the REHG only contains the ±1 orders, no order selection mask is ever needed for the REHG-LSI. The simulations and the experiments show that the REHG-LSI exhibits strong adaptability, nice repeatability, and high precision.

General measurement of optical system aberrations with a continuously variable lateral shear ratio by a randomly encoded hybrid grating.

A general lateral shearing interferometry method to measure the wavefront aberrations with a continuously variable shear ratio by the randomly encoded hybrid grating (REHG) is proposed. The REHG consists of a randomly encoded binary amplitude grating and a phase chessboard. Its Fraunhofer diffractions contain only four orders which are the ±1 orders in two orthogonal directions due to the combined modulation of the amplitude and phase. As a result, no orders selection mask is needed for the REHG and the shear ratio is continuously variable, which is beneficial to the variation of sensitivity and testing range for different requirements. To determine the fabrication tolerance of this hybrid grating, the analysis of the effects of different errors on the diffraction intensity distributions is carried out. Experiments have shown that the testing method can achieve a continuously variable shear ratio with the same REHG, and the comparison with a ZYGO GPI interferometer exhibits that the aberration testing method by the REHG is highly precise and also has a good repeatability. This testing method by the REHG is available for general use in testing the aberrations of different optical systems in situ.

[Impact of Vegetation Structure on Drought Indices Based on MODIS Spectrum].

The drought indices based on MODIS spectral reflectance data are widely used for drought characterization and monitoring in agricultural context. Based on the PROSAIL model and MODIS observational data in Shandong in 2010, the present paper studied the impact of vegetation structure of leaf area index and physiological growth cycle on MODIS spectral drought index. The results showed that the reflectance of three MODIS bands in spectrum of near-infrared and shortwave infrared changes significantly with leaf water content of vegetation. Therefore, the five kinds of MODIS spectral drought index constructed by those MODIS bands can be used to monitor the leaf water content of vegetation. However, all drought indices are affected by leaf area index. In general, the impact is serious in the case of low LAI values and is weakened with the increase in LAI value. The study found that physiological vegetation growth cycle also affects the magnitude of MODIS spectral drought indices. In conclusion, the impact of vegetation structure must be carefully considered when using MODIS spectral drought indices to monitor drought. The conclusion of this study provides a theoretical basis for remote sensing of drought monitoring.

Common-path and compact wavefront diagnosis system based on cross grating lateral shearing interferometer.

A common-path and compact wavefront diagnosis system for both continuous and transient wavefronts measurement is proposed based on cross grating lateral shearing interferometer (CGLSI). Derived from the basic CGLSI configuration, this system employs an aplanatic lens to convert the wavefront under test into a convergent beam, which makes it possible for CGLSI to test the wavefront of collimated beams. A geometrical optics model for grating pitch determination and a Fresnel diffraction model for order selection mask design are presented. Then a detailed analysis about the influence of the grating pitch, the distance from the cross grating to the order selection mask and the numerical aperture of the aplanatic lens on the system error is made, and a calibration method is proposed to eliminate the system error. In addition, the differential Zernike polynomials fitting method is introduced for wavefront retrieval. Before our experiment, we have designed several grating pitches and their corresponding order selection mask parameters. In the final comparative experiment with ZYGO interferometer, the wavefront diagnosis system exhibits both high precision and repeatability.