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The exact pathophysiology of the spaceflight-associated neuro-ocular syndrome (SANS) has so far not been completely elucidated. In this study we assessed the effect of acute head-down tilt position on the mean flow of the intra- and extracranial vessels. Our results suggest a shift from the external to the internal system that might play an important role in the pathomechanism of SANS.

Diabetic retinopathy (DR) is one of the most serious microvascular complications of diabetes mellitus (DM). MicroRNAs (miRNAs) have been discovered to play a crucial role in DR, but the mechanisms underlying the effects of miR-301a-3p on DR are poorly understood. This paper was designed to explore the possible role of miR-301a-3p in DR. The diabetic rat model was established by a single intraperitoneal injection of streptozotocin (STZ). The effects of miR-301a-3p on the biological functions of HRECs were determined through a series of experiments in vitro/vivo. The results revealed that interference with miR-301a-3p could decrease the expressions of inflammatory factors and apoptosis in the retinal tissue of DR. Furthermore, it can alleviate the oxidative stress in DR serum, reduce VEGF expression, increase endothelial cell marker expression, and inhibit (High Glucose) HG-induced apoptosis of HRECs. Six-transmembrane epithelial antigen of prostate 4 (STEAP4) was the target of miR-301a-3p. All the effects of miR-301a-3p in DR model were reversed by STEAP4 inhibitor. miR-301a-3p promotes diabetic retinopathy via regulation of STEAP4. The findings in this study may provide a vital reference for the drug research and development in DR treatment.

High-throughput (HTP) experiments play key roles in accelerating the discovery of advanced materials, but the HTP preparation and characterization, especially for bulk samples, are extremely difficult. In this work, we developed a novel and general strategy for HTP screening of high-performance bulk thermoelectric materials. The performed full-chain HTP experiments cover rapid synthesis of the bulk sample with quasi-continuous composition, microarea phase identification and structure analysis, and measurement of the spatial distribution of the sample composition, electrical and thermal transport properties. According to our experiments, bulk Bi2− x Sb x Te3 ( x = 1–2) and Bi2Te3− x Se x ( x = 0–1.5) samples with quasi-continuous compositions have been rapidly fabricated by this HTP method. The target thermoelectric materials with the best Sb/Bi and Te/Se ratios are successfully screened out based on subsequent HTP characterization results, demonstrating that this HTP technique is effective in speeding up the exploration of novel high-performance thermoelectric materials.

A new green composite microsphere (SA/ML-BT) was prepared from sodium alginate by interspersing modified lignin–bentonite clay (ML-BT) and its adsorption performance to Hg (II) from aqueous solution in a batch mode and column mode was systematically investigated. The morphology and structure of the SA/ML-BT were characterized by SEM, XRD and FTIR. BET analysis showed that the pore type of SA/ML-BT is mainly mesoporous. The enlarged surface area of 5.98 m2/g and the insertion of SA improved the attraction of Hg (II) to porous surface. In batch tests, different initial Hg (II) concentration, pH values and contact time were studied, which were fitted with pseudo-first-order, pseudo-second-order kinetic models and Langmuir/Freundlich isotherms. Zeta potential analysis showed that isoelectric point charge of SA/ML-BT was 3.24 and Hg (II) removal rate increased with pH increasing in the range of 1 to 3 then kept the maximum value of 93% in the range of 3 to 9. Likewise, in the fixed-bed column tests, the effects of initial concentration (10–30 mg/L), bed height (1–3 cm) and influent flow rate (0.5–1.5 mL/min) were evaluated, which were fitted with Yoon–Nelson and Bohart–Adam models. The SA/ML-BT remained 85% removal rate after three repeated cycles, which indicated a promising potential in sustainable applications. A removal capacity of 24.4 mg/g in batch and 42.1 mg/g in column tests were obtained respectively. These findings revealed that the proposed SA/ML-BT has great potential for metallic cation remediation.

Lignocellulosic materials have received wide interest in adsorption of contaminants in water due to their abundance, eco-friendliness, and low cost. However, the development of new adsorbents from lignocellulose with excellent performance is still a big challenge. In this work, a new bowl-shaped biosorbent (BSB) with surface functionality is prepared from lignin that is extracted from the abundant sugarcane bagasse. The product is characterized by scanning electron microscopy, infrared spectrum, thermo gravimetric analysis and N2 adsorption techniques. The results show that the obtained BSB is obviously bowl-shaped in microscale with an enlarged surface area, and contains numerous oxygen and nitrogen functional groups. It exhibits an enhanced adsorption capacity toward Cd2+ that is 3.2 times of the original lignin. The adsorption process of Cd2+ by the BSB is well fitted by the Freundlich isothermal model and the pseudo-second-order kinetic model, respectively. The adsorption mechanism involves surface complexation, ion-exchange, electrostatic attraction, chemical precipitation and physical adsorption, etc., among them, the surface complexation is the rate-controlling step. Moreover, it shows a good reusability during five repeated cycling for Cd2+ adsorption.

This study aimed to report the occurrence of benign paroxysmal positional vertigo (BPPV) in a 90-day head-down bed rest experiment and evaluate the potential relationship between BPPV-related seizures and bone metabolic changes. Five cases of lateral semicircular canal (LSC) BPPV were diagnosed during a 90-day head-down bed rest experiment. Five age-matched subjects who participated in this experiment and never felt dizziness or vertigo were assigned as controls. The differences between the BPPV and the controls in lumbar bone mineral density, 25-hydroxyvitamin D level, corrected serum calcium, potassium, sodium, phosphorus, iron, uric acid and N-terminal osteocalcin were analyzed to determine the cause of LSC-BPPV. BPPV occurred from Day 17 to Day 42 during head-down bed rest. The occurrences of BPPV were related to low 25-hydroxyvitamin D level (BPPV:20.70 ± 1.95 ng/L vs. control: 30.59 ± 2.75 ng/L at Day 30 during HDBR, p

Inflammatory bowel disease (IBD) is an important risk factor for colon cancer. Novel serum immunoinflammation-related protein complexes (IIRPCs) have shown associations with early cancer detection. Herein, we investigated the potential of serum IIRPCs for discriminating between IBD and colorectal cancer (CRC) patients. Serum protein complexes of 65 healthy controls, 57 CRC, 69 (ulcerative colitis) UC, and 67 (Crohn's disease) CD patients were isolated by native-PAGE. The gray values of serum IIRPCs bands in the gel were quantified using Quantity One software. The receiver-operating characteristic (ROC) curves were constructed to assess the discriminating ability by calculating the area under the ROC curve. The serum IIRPCs levels in IBD and CRC patients were significantly elevated compared to healthy controls. ROC analysis indicated certain diagnostic ability of serum IIRPCs in differentiating IBD from CRC. Specifically, “a3” complex discriminated UC from CRC, with an AUC value of 0.722, sensitivity of 69.4% and specificity of 63.8%. Similarly, “b4” complex discriminated UC from CRC, with an AUC value of 0.709, sensitivity of 70.4%, and specificity of 60.0%. In addition, the “a3” complex also discriminated CD from CRC, with an AUC value of 0.785, sensitivity of 73.1%, and specificity of 74.1%, while the “b4” complex showed a tendency to discriminate CD from CRC, with an AUC value of 0.663, sensitivity of 67.9% and specificity of 50.0%. Thus, an equation based on multiple IIRPCs was built to further improve the discriminating power. Serum IIRPCs can be used to discriminate IBD from CRC and may also be associated with early screening of colitis-associated cancer.

In saline water flotation, the salinity can cause a distinguishable slime coating of clay minerals on chalcopyrite particles through its effect on their electrical double layers in aqueous solutions. In this work, kaolinite was used as a representative clay mineral for studying slime coating during chalcopyrite flotation. The flotation of chalcopyrite in the presence and absence of kaolinite in tap water, seawater, and gypsum-saturated water and the stability of chalcopyrite and kaolinite particles in slurries are presented. Zeta-potential distributions and scanning electron microscopy images were used to characterize and explain the different slime coating degrees and the different flotation performances. Kaolinite particles induced slime coating on chalcopyrite surfaces and reduced chalcopyrite floatability to the greatest extent when the pH value was in the alkaline range. At 0.24wt% of kaolinite, the chalcopyrite floatability was depressed by more than 10% at alkaline pH levels in tap water. Salinity in seawater and gypsum-saturated water compressed the electrical double layers and resulted in extensive slime coating.

Here we present a visual reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for detecting the gene encoding the σB major outer-capsid protein of novel duck reovirus (NDRV). A set of primers, composed of two outer primers, two inner primers and two loop primers, was designed based on the gene of interest. The LAMP reaction was conducted in a traditional laboratory water bath at 65 °C for 50 min. We compared the performance of calcein/Mn2+ and SYBR Green I dyes, as well as electrophoresis on agarose gel stained with GoldView nucleic acid dye to detect the RT-LAMP-amplified products and all assays could be employed to discriminate between positive and negative specimens in visible or UV light. Our data showed that there is no cross-reaction with other viruses and the RT-LAMP technique displayed high sensitivity for detecting NDRV with a minimal detection limit of 200 fg RNA input. This assay was more sensitive than conventional PCR in detecting NDRV both in natural and experimental infection. In conclusion, the RT-LAMP technique was remarkably sensitive, specific, rapid, simple and profitable for the identification of NDRV.

Changes in serum lipidome and in tissue lipidome are associated with cancer. In this study, tissue mass spectrometry imaging (MSI) and serum lipid profiling by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) were performed to investigate significantly changed lipids in both tumor (malignant thyroid cancer (MTC) and benign thyroid tumor (BTT)) tissues and sera. Y-scatterplots of variable importance in the projection (VIP) values vs. fold change values indicate that change trends in the levels of ten lipids (i.e., phosphatidylcholine (PC)(34:1), PC(36:1), PC(38:6), phosphatidic acid (PA) (36:2), PA(36:3), PA(38:3), PA(38:4), PA(38:5), PA(40:5), and sphingomyelin (SM)(34:1)) in both tissues and sera from MTC patients, BTT patients, and normal individuals are significantly associated with these three types of pathophysiological status. In order to examine their diagnostic ability, 289 serum samples from 124 MTC patients, 43 BTT patients, and 122 normal controls were randomly divided into the training set and validation set. A biomarker of PC(34:1) exhibited excellent diagnostic ability to differentiate both MTC and BTT patients from normal individuals, with an area under the receiver operating characteristic (ROC) curve value of 0.984, a sensitivity of 96.4 %, and a specificity of 92.7 %. A panel which included PA(36:3) and SM(34:1) could distinguish between MTC and BTT, with an area under receiver operating characteristic curve (AUC) of 0.961, a sensitivity of 87.8 %, and a specificity of 92.9 %. It is worth noting that a panel consisting of PC(34:1), PA(36:3), and SM(34:1) could differentiate MTC patients from both BTT patients and normal individuals, with an AUC of 0.841, a sensitivity of 86.6 %, and a specificity of 75.5 %.

We reported the development of an evanescent-wave quartz-enhanced photoacoustic sensor (EW-QEPAS) using a single-mode optical fiber tip for sensitive gas detection in the extended near-infrared region. It is a spectroscopic technique based on the combination of quartz-enhanced photoacoustic spectroscopy with fiber-optic evanescent-wave absorption to achieve low optical noise, easy optical alignment, and high compactness. Carbon monoxide (CO) detection at 2.3 μm using a fiber-coupled, continuous-wave, distributed-feedback laser was selected for the sensor demonstration. By tapering the optical fiber down to 2.5 μm diameter using the flame-brushing technique, an evanescent field of ~0.6 mW around the fiber tip was absorbed by CO molecules. Besides an excellent linear response (R 2 = 0.9996) to CO concentrations, the EW-QEPAS sensor achieved a normalized noise-equivalent absorption (NNEA) coefficient of 8.6 × 10−8 cm−1W/√Hz for an incident optical power of 1.8 mW and integration time of 1 s. The sensor detection sensitivity can be further improved by enhancing the evanescent-wave power on the fiber tip.

Skeletal unloading induced by disuse or immobilization causes a decrease in bone mass and strength. We investigated the relationship between whole-body vibration (WBV) and resistance exercise (RE) in preventing bone loss induced by 8-week hindlimb unloading in young male rats. Sixty male Wistar rats were assigned randomly to 6 groups: age-matched control group (CON, n = 10), hindlimb unloading group (HU, n = 10), hindlimb unloading + standing group (HU + ST, n = 10), hindlimb unloading + WBV group (HU + WBV, n = 10), hindlimb unloading + RE group (HU + RE, n = 10) and hindlimb unloading + WBV + RE group (HU + WBV + RE, n = 10). After 8-week hindlimb unloading, micro-CT scanning and three-point bending test were performed in the femur. Sera were collected for analysis of bone formation and resorption markers. Compared with HU group, WBV, RE and the combination of WBV and RE (WBV + RE) significantly improved (P 0.01) one repetition maximum (1RM) (expressed as the percentage change from baseline, HU: -23%, HU + WBV: 21%, HU + RE: 48%, HU + WBV + RE: 51%), and maintained (P 0.05) cancellous volumetric bone mineral density (vBMD) and trabecular structure. No difference of cortical vBMD was found among all groups (P 0.05). WBV had no effects on biomechanical properties of the femur diaphysis (P 0.05). RE and WBV + RE significantly increased maximum load and cross-sectional moment of inertia of the femur diaphysis in hindlimb unloading rats (P 0.05). There was an interaction between WBV and RE in improving cancellous bone. These results demonstrate that WBV and RE interactively maintain cancellous structure and vBMD, and independently partially mitigate the reduction of bone strength in long-term hindlimb unloading rats.

Anthropogenic factors have contributed to a severe decline of Leptobotia elongata. Conservation information of L. elongata will be required. Here, 14 tetranucleotide microsatellite DNA markers were developed from L. elongata through high-throughput (454) sequencing data. Twenty-four individuals of the species were genotyped using these markers. All of the loci displayed a high level of polymorphism with the number of alleles per locus ranged from 7 to 23, polymorphism information content ranged from 0.650 to 0.943. Observed and expected heterozygosities ranged from 0.609 to 1.000 and from 0.699 to 0.967, respectively. These markers provide an excellent toolkit to study population genetic structure and would benefit the conservation of this species.

Mink enteritis virus (MEV) is one of the most important pathogens in the mink industry. Recent studies have shed light into the role of microRNAs (miRNAs), small noncoding RNAs of length ranging from 18–23 nucleotides (nt), as critical modulators in the host-pathogen interaction networks. We previously showed that miRNA miR-181b can inhibit MEV replication by repression of viral non-structural protein 1 expression. Here, we report that two other miRNAs (miR-320a and miR-140) inhibit MEV entry into feline kidney (F81) cells by downregulating its receptor, transferrin receptor (TfR), by targeting the 3′ untranslated region (UTR) of TfR mRNA, while being themselves upregulated.

Experiments with styrene (St) and acrylate monomer [methyl acrylate (MA), ethyl acrylate (EA) and butyl acrylate (BA)] prove that copolymerization can be initiated in two monomers with intense ultrasound. Within the experimental range, the yields of copolymer increase with rise of ultrasonic intensity, reaction time, temperature and the amount of ion surfactants (sodium dodecyl sulfate (SDS), hexadecyltrimethyl ammonium bromide (CTAB)), but decrease with increasing concentration of comonomers. The comonomer ratio and surfactant types have considerable effect on the yield of copolymer. The yield of copolymer is 38.8% by irradiating 10% BA/St (1/1, v/v) at 40°C with 600 w for 1h.

Answer to the rhythm puzzle The answer is ventricular tachycardia with frequent retrograde P waves. The 12-lead onset ECG showed the QRS complex morphology in lead V1 where prominent R waves are seen, similar to the pattern of right bundle branch block. It was evident that there were notched waves following most of QRS complexes (Fig. 2, arrow). The notched wave was irregular in itself and related to the QRS complex. The above patterns were supportive of ventricular tachycardia with frequent retrograde atrioventricular conduction. Invasive electrophysiological study was undertaken to confirm the relationship between the atrium and ventricle. Intracardiac recording of coronary sinus electrodes more clearly showed the retrograde atrioventricular conduction. The missing retrograde P wave was probably due to sinus node interference (Fig. 3, arrow). So, the diagnosis is ventricular tachycardia with frequent retrograde atrioventricular conduction, which was further confirmed by successful ablation with radiofrequency post-medially of left ventricular septum. The tachycardia origin is near the left posterior fascicle of the left bundle branch, which explains why the QRS complex duration is not overtly wide. The patient is asymptomatic after 1 year of follow-up. Fig. 2 The 12-lead surface ECG during onset of palpitation. Arrow denotes retrograde P wave Fig. 3 Intracardiac recording in invasive electrophysiological study. Arrow denotes missing retrograde P wave due to sinus node interference. CS = coronary sinus, RVA = right ventricular apex

A 30-year-old woman was admitted to our Cardiology Department with sustained palpitations for 10 h. She had suffered from paroxysmal palpitations for 3 months. This happened two to five times every week, especially in the month before admission and syncope occurred occasionally. Intravenous injection of propafenone or adenosine was used to terminate the acute episodes of palpitations. There were two different types of onset electrocardiogram (ECG) with a fast and regular rhythm, one was with normal QRS complexes, the other was with wide QRS complexes. The heart was normal on an ultrasonic examination and emission computed tomography. The usual electrocardiogram was undertaken (Fig. 1, upper panel). The significant episode was documented by Holter monitoring (Fig. 1, lower panel). What is your diagnosis?

A 37-year-old man was admitted to our cardiology department with sustained palpitations for 36 hours. He had suffered from paroxysmal palpitations for five years. This had happened one to three times per month, especially in the six months before admission and syncope occurred occasionally. The most useful way to terminate the acute episode of palpitations was a loading dose of propafenone (up to 210 mg). The patient had been diagnosed with dilated cardiomyopathy seven years ago by an ultrasound examination. The onset electrocardiogram (ECG) was a fast and regular rhythm with wide QRS complexes (174 beats/min). During the administration of propafenone, the following ECG was documented (figure 1). What is your diagnosis?