An investigation into the correlation between visual performance in simulated complex environments and academic attainment among primary school students.

Traditional vision screenings in schools are limited to simple visual tasks, yet students in their daily learning face more complex visual environments. Binocular rivalry tasks can partially simulate the visual challenges of real visual environments and activate advanced visual processing mechanisms that simple visual tasks cannot. Therefore, by superimposing binocular rivalry-state tasks onto simple visual tasks, we have developed an innovative vision screening program to rapidly and extensively assess students' visual performance in complex environments. This is a cross-sectional study in which we investigated the performance of 1126 grade 1-6 students from a primary school in Wuxi, China, in rivalry-state stereoscopic vision tasks. The correlation between the screening results of 1044 students and their academic achievements was also statistically analyzed. The study results revealed pass rates of 53.5-60.5% across various visual tests. Specifically, for first-grade students, there was a statistically significant difference in standardized Chinese scores between the group that failed and the group that passed the rivalry-state stereoscopic vision test (- 0.49 ± 3.42 vs. 0.22 ± 0.58, t = - 2.081, P = 0.04). This result underscores the importance of focusing on the visual adaptability of first graders in complex environments.Trail registration: Ethics Committee of Affiliated Children's Hospital of Jiangnan University-Certificate number: WXCH2022-04-027.

Composite Flexible Sensor Based on Bionic Microstructure to Simultaneously Monitor Pressure and Strain.

To achieve the human sense of touch, a strain sensor needs to be coupled with a pressure sensor to identify the compliance of the contacted material. However, monitoring the pressure-strain signals simultaneously and ensuring no coupling effect between the two signals is the technical bottleneck for the flexible tactile sensor to. Herein, a composite flexible sensor based on microstructures of lotus leaf is designed and manufactured, which integrates the capacitive pressure sensor and the resistance strain sensor into one pixel to realize the simultaneous detection of pressure and strain. The electrode layer of the capacitance sensor also plays the role of the resistance strain sensor, which greatly simplifies the structure of the composite flexible sensor and obtains the compact size to integrate more easily. The device can simultaneously detect pressure and deformation, and more importantly, there is no coupling effect between the two kinds of signals. Here, the sensor has high pressure sensitivity (0.784 kPa-1 when pressure less than 100 kPa), high strain sensitivity (gauge factor = 4.03 for strain 0-40%), and can identify materials with different compliance, which indicates the tactile ability as the human skin performs.

ASIC1 inhibition impairs the proliferation and migration of pancreatic stellate cells induced by pancreatic cancer cells.

Activated pancreatic stellate cells (PSCs) with an increased proliferation and migration ability are the partners in crime with pancreatic cancer cells. Acid-sensing ion channel 1 (ASIC1) is expressed in pancreatic cancer and PSCs, and especially, it mediates the activation of PSCs. However, whether ASIC1 is involved in pancreatic cancer cells-induced biological behavior re-educating of PSCs is unclear. In this study, the change of ASIC1 expression in PSCs and pancreatic cancer Panc-1 cells after in-direct co-culture was detected by western blotting, and the proliferation and migration of PSCs with ASIC1 knockdown under Panc-1 cells-conditioned medium (Panc-1-CM) was assessed. The results showed that pancreatic cancer cells induced ASIC1 overexpression, and the enhanced proliferation and migration of PSCs was weakened by ASIC1 inhibition. In addition, the extracellular signal-regulated kinase (ERK) expression in PSCs remained stable, but the phosphorylated ERK (p-ERK) expression in PSCs treated with Panc-1-CM increased, which was suppressed by ASIC1 knockdown. These results indicate that ASIC1 participates in the regulation of PSCs proliferation and migration induced by cancer cells via the ERK pathway, and ASIC1 inhibition may be beneficial to pancreatic cancer treatment.

Downregulating lncRNA PRNCR1 ameliorates LPS-induced pulmonary vascular endothelial cell injury by modulating miR-330-5p/TLR4 axis.

Pulmonary vascular endothelial cell (PVEC) injury following acute lung injury or acute respiratory distress syndrome seriously affects disease development. Recently, accumulating evidence has suggested that long noncoding RNA (lncRNA) exerts significant effects in vascular endothelial cell injury. However, PRNCR1, a novel lncRNA, remains scarcely understood in terms of its functions in PVEC injury. Both in vivo and in vitro models of PVEC injury were constructed by lipopolysaccharide (LPS) administration. The relative expressions of PRNCR1, miR-330-5p, and TLR4 were detected by quantitative reverse transcription-polymerase chain reaction, Western blot, and immunohistochemistry. Besides, gain and loss assays of PRNCR1/miR-330-5p were conducted to verify their effects on LPS-induced PVEC injury. Cell Counting Kit-8 assay used to measure cell viability and flow cytometry was used to detect apoptosis. Besides, the protein levels of caspase 3, nuclear factor-κB (NF-κB), and inflammatory cytokines (including tumor necrosis factor-α, interleukin-1ß [IL-1ß], and IL-6) were evaluated via Western blot and enzyme-linked immunosorbent assay. Moreover, a dual-luciferase activity experiment and RNA immunoprecipitation were applied to confirm the targeting relationship between PRNCR1 and miR-330-5p, miR-330-5p, and TLR4. PRNCR1 and TLR4 levels were significantly upregulated in LPS-treated PVEC, both in vivo and in vitro, while miR-330-5p were downregulated. Inhibiting PRNCR1 or overexpressing miR-330-5p markedly attenuated LPS-induced PVEC injury, expressions of TLR4, NF-κB, and inflammatory cytokines. Mechanistically, PRNCR1 functioned as a competitive endogenous RNA by sponging miR-330-5p and then promoting TLR4 expression. PRNCR1 was upregulated in LPS-induced PVEC and aggravated its injury via modulating the miR-330-5p/TLR4 axis.

Mechanism of pulsatile flushing technique for saline injection via a peripheral intravenous catheter.

BACKGROUND: The underlying mechanism of pulsatile flushing technique has not been fully elucidated, and the partial understanding of the mechanism has been confined to hydrodynamic simulation, ignoring the dynamic interaction among the catheter, blood vessel, blood stream, and saline. METHODS: The peripheral intravenous catheter and vein models and their internal flow fields were assessed using a commercial software. The parameters of both fluid and structural mechanics were calculated and compared in the push and pause phase. The effect of different flushing volumes per bolus before each pause (0.5, 1.0, 1.5, and 2.0 mL) were compared, respectively corresponding to group (A, B, C and D). FINDINGS: In groups C and D, the wall shear stress value (≥2 Pa) and enhanced shear rates (peaks up to 10,000 s-1) were higher in the vessel wall near the catheter tip, which may be at risk of vascular endothelial injury. Furthermore, extraluminal flushing might be attributed to the recirculation of jet from the catheter outlet. The vortices of all groups faded away in an extremely short period (≤0.1 s) if the push was suddenly discontinued. Finally, overlarge displacement of the catheter tip in groups C and D (0.91 and 1.1 mm, respectively) caused the peripheral intravenous catheters to angle with the venous wall. INTERPRETATION: The pulsatile flushing technique can facilitate intra- and extraluminal flushing of peripheral intravenous catheters. Furthermore, an insufficient volume per bolus can lead to inefficient flushing, and an overdose of single push may cause mechanical endothelial injury.

Prevalence, causes and risk factors of reduced VA and persistent reduced VA among preschool children in Eastern China.

AIMS: To determine prevalence, causes, and risk factors of reduced uncorrected visual acuity (UCVA), reduced presenting visual acuity (PVA), and persistent reduced visual acuity (VA) among Chinese preschool children. METHODS: The longitudinal, population-based Nanjing Eye Study (NES) was carried out. Children underwent baseline comprehensive ocular examinations in 2016 (at 48-60 months old) and the follow-up ocular examinations in 2017. A comprehensive questionnaire about children and their families was completed by their legal guardians. For children having reduced PVA at baseline, a follow-up questionnaire about potential factors concerning VA correction was completed. Reduced VA was defined as VA worse than 0.30 logMAR (Snellen equivalent 6/12, 20/40), and persistent reduced VA was defined as reduced PVA in both 2016 and 2017. RESULTS: Among 1448 participants with both eye examinations and questionnaires completed, prevalence of reduced UCVA, reduced PVA, and persistent reduced VA at age of 60-72 months were 5.94%, 3.04%, and 1.59% respectively. Causes for reduced PVA were refractive error (79.5%), amblyopia (18.2%), and amblyopia combined nystagmus (2.3%). Among 23 children having persistent reduced VA, causes of reduced PVA remained unchanged in 13 children and 4 children developed amblyopia from refractive error. Younger age (OR = 1.09 for each month decrease, p = 0.01) and non-breastfeeding (OR = 2.08, p = 0.03) were risk factors for reduced UCVA. Younger children with reduced UCVA were at higher risk of having reduced PVA (OR = 1.18 for each month decrease, p = 0.04). Children with siblings (OR = 5.95, p = 0.02) were more likely to have persistent reduced VA. CONCLUSIONS: Future vision health promotion strategies among preschool children should focus on early vision-screening and timely refractive correction. Apart from children of non-breastfeeding mothers, attention should also be paid to children with siblings.

Vitreomacular adhesion or vitreomacular traction may affect antivascular endothelium growth factor treatment for neovascular age-related macular degeneration.

OBJECTIVE: The aim of this review is to determine whether vitreomacular adhesion (VMA) or vitreomacular traction (VMT) has an influence on the outcomes of antivascular endothelium growth factor (anti-VEGF) treatment neovascular age-related macular degeneration (nAMD). METHODS: A systematic literature search was performed in Pubmed.gov, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang, SinoMed and ClinicalTrials.gov up to 30 June 2016 to identify eligible studies. RESULTS: Nine studies and 2212 participants were finally identified. At month 6, the mean improvement in best-corrected visual acuity (BCVA) and mean decline in central retinal thickness (CRT) of the VMA/VMT(+) group was less than that of the VMA/VMT(-) group (95% CI -3.05 to -0.96 letters, p=0.0002; 15.53 to 32.98 µm, p<0.00001; respectively); at month 12, there was a small or only marginally significant difference (-0.01 to 2.00 letters, p=0.05; 0.17 to 23.7 µm, p=0.05; respectively) between the groups. During the 12 months, however, the VMA/VMT(+) group required more injections ((0.25 to 0.95), p=0.0008). CONCLUSIONS: In using anti-VEGF drugs to treat nAMD, clinicians should take into account the fact that concurrent VMA or VMT might antagonise the efficacy of anti-VEGF drugs during the early stage of treatment.

Rapid Preparation of Released N-Glycans for HILIC Analysis Using a Labeling Reagent that Facilitates Sensitive Fluorescence and ESI-MS Detection.

N-glycosylation of proteins is now routinely characterized and monitored because of its significance to the detection of disease states and the manufacturing of biopharmaceuticals. At the same time, hydrophilic interaction chromatography (HILIC) has emerged as a powerful technology for N-glycan profiling. Sample preparation techniques for N-glycan HILIC analyses have however tended to be laborious or require compromises in sensitivity. To address these shortcomings, we have developed an N-glycan labeling reagent that provides enhanced fluorescence response and MS sensitivity for glycan detection and have also simplified the process of preparing a sample for analysis. The developed labeling reagent rapidly reacts with glycosylamines upon their release from glycoproteins. Within a 5 min reaction, enzymatically released N-glycans are labeled with this reagent comprised of an NHS-carbamate reactive group, a quinoline fluorophore, and a tertiary amine for enhancing ESI+ MS ionization. To further expedite the released N-glycan sample preparation, rapid tagging has been integrated with a fast PNGase F deglycosylation procedure that achieves complete deglycosylation of a diverse set of glycoproteins in approximately 10 min. Moreover, a technique for HILIC-SPE of the labeled glycans has been developed to provide quantitative recovery and facilitate immediate HILIC analysis of the prepared samples. The described approach makes it possible to quickly prepare N-glycan samples and to incorporate the use of a fluorescence and MS sensitivity enhancing labeling reagent. In demonstration of these new capabilities, we have combined the developed sample preparation techniques with UHPLC HILIC chromatography and high sensitivity mass spectrometry to thoroughly detail the N-glycan profile of a monoclonal antibody.

Selective TRAIL-induced cytotoxicity to lung cancer cells mediated by miRNA response elements.

Lung cancer is among the most common cancers, and the current therapeutic strategies are still inefficient in most cases. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising biological agent for cancer treatment because of its potent pro-apoptotic effect on cancer cells. However, TRAIL also induces apoptosis in normal cells and therefore may cause toxicity to normal tissues if clinically applied. To address this issue, we inserted microRNA response elements (MREs) of miR-133a, miR-137 and miR-449a, which are all underexpressed in lung cancer cells, into an adenoviral vector to regulate TRAIL expression. This MRE-regulated vector (Ad-TRAIL-MRE) was able to express TRAIL in a lung-cancer-specific fashion. No TRAIL expression was detected in normal cells. Consistently, Ad-TRAIL-MRE exerted cytotoxicity to lung cancer cells, rather than normal cells, perhaps via inducing selective apoptosis. The selective TRAIL-mediated growth-inhibiting effect was further confirmed in a tumour xenograft model. Also, Ad-TRAIL-MRE only resulted in very low hepatotoxicity when applied. Collectively, we generated a novel TRAIL-expressing adenoviral vector that was regulated by MREs. This strategy permits TRAIL expression in a lung-cancer-specific manner and is worth further studying for clinical trials.

Comprehensive characterization of the N-glycosylation status of CD44s by use of multiple mass spectrometry-based techniques.

The CD44 family are type-1 transmembrane glycoproteins which are important in mediating the response of cells to their microenvironment, including regulation of growth, survival, differentiation, and motility. All these important functions have been reported to be regulated by N-glycosylation; however, little is known about this process. In the CD44 family, the most prolific isoform is CD44 standard type (CD44s). In this work, an integrated strategy combining stable isotope labeling, chemical derivatization, hydrophilic-interaction liquid chromatographic (HILIC) separation, and mass spectrometric (MS) identification was used to perform a comprehensive qualitative and quantitative survey of the N-glycosylation of recombinant CD44s. Specifically, the occupation ratios of the N-glycosites were first determined by MS with (18)O labeling; the results revealed five glycosites with different occupation ratios. Next, N-glycans were profiled by chemical derivatization and exoglycosidase digestion, followed by MALDI-TOF-MS and HILIC-ESI-MS-MS analysis. Interestingly, the quantitative analysis showed that non-sialylated, fucosylated complex-type glycans dominated the N-glycans of CD44s. Furthermore, the site-specific N-glycan distributions profiled by LC-ESI-MS(E) indicated that most glycosites bore complex-type glycans, except for glycosite N100, which was occupied by high-mannose-type N-glycans. This is the first comprehensive report of the N-glycosylation of CD44s. Figure Strategies for characterization of the N-glycosylation status of CD44s.

Characterization of glycoprotein digests with hydrophilic interaction chromatography and mass spectrometry.

A new hydrophilic interaction chromatography (HILIC) column packed with amide 1.7 µm sorbent was applied to the characterization of glycoprotein digests. Due to the impact of the hydrophilic carbohydrate moiety, glycopeptides were more strongly retained on the column and separated from the remaining nonglycosylated peptides present in the digest. The glycoforms of the same parent peptide were also chromatographically resolved and analyzed using ultraviolet and mass spectrometry detectors. The HILIC method was applied to glyco-profiling of a therapeutic monoclonal antibody and proteins with several N-linked and O-linked glycosylation sites. For characterization of complex proteins with multiple glycosylation sites we utilized 2D LC, where RP separation dimension was used for isolation of glycopeptides and HILIC for resolution of peptide glycoforms. The analysis of site-specific glycan microheterogeneity was illustrated for the CD44 fusion protein.

Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) and UPLC/MS(E) analysis of RNA oligonucleotides.

Fast and efficient ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) analysis of short interfering RNA oligonucleotides was used for identity confirmation of the target sequence-related impurities. Multiple truncated oligonucleotides and metabolites were identified based on the accurate mass, and their presumed sequence was confirmed by MS/MS and MS(E) (alternating low and elevated collision energy scanning modes) methods. Based on the resulting fragmentation of native and chemically modified oligonucleotides, it was found that the MS(E) technique is as efficient as the traditional MS/MS method, yet MS(E) is more general, faster, and capable of producing higher signal intensities of fragment ions. Fragmentation patterns of modified oligonucleotides were investigated using RNA 2'-ribose substitutions, phosphorothioate RNA, and LNA modifications. The developed sequence confirmation method that uses the MS(E) approach was applied to the analysis of in vitro hydrolyzed RNA oligonucleotide. The target RNA and metabolites, including the structural isomers, were resolved by UPLC, and their identity was confirmed by MS(E). Simultaneous RNA truncations from both termini were observed. The UPLC quadrupole time-of-flight (QTOF) MS/MS and MS(E) methods were shown to be an effective tool for the analysis and sequence confirmation of complex oligonucleotide mixtures.

Phosphopeptide enrichment using microscale titanium dioxide solid phase extraction.

Identification of phosphopeptides by MS is challenging due to their relatively low abundance in proteomic samples and their limited ionization efficiency. Various affinity enrichment methods have been used in the literature. Titanium dioxide SPE devices have been recently proposed as an alternative to immobilized metal affinity chromatography for phosphopeptide enrichment. This study evaluates the TiO(2 )method using sorbent packed in a 96 well microscale extraction plate operated using a vacuum manifold. The phosphopeptide recovery and enrichment selectivity were investigated at various loading conditions. The effectiveness of organic additives such as dihydroxybenzoic acid derivatives and other nonaliphatic carboxylic acids on enrichment selectivity was examined. The performance of TiO(2) was compared to IMAC sorbent. The results suggest that various additives improve the enrichment selectivity by effectively interfering with the acidic peptides binding to TiO(2) sorbent. Interaction of phosphopeptides with sorbent is also affected, which leads to overall reduction in phosphopeptide recovery. The new SPE device was successfully utilized for the extraction of phosphopeptides from yeast lysate digest using 2,5-dihydroxybenzoic acid to minimize the interference from nonphosphorylated peptides.

Mixed-mode chromatography for fractionation of peptides, phosphopeptides, and sialylated glycopeptides.

A mixed-mode chromatographic (MMC) sorbent was prepared by functionalizing the silica sorbent with a pentafluorophenyl (PFP) ligand. The resulting stationary phase provided a reversed-phase (RP) retention mode along with a relatively mild strong cation-exchange (SCX) retention interaction. While the mechanism of interaction is not entirely clear, it is believed that the silanols in the vicinity of the perfluorinated ligand act as strongly acidic sites. The 2.1 mm x 150 mm column packed with such sorbent was applied to the separation of peptides. Linear RP gradients in combination with salt steps were used for pseudo two-dimensional (2D) separation and fractionation of tryptic peptides. An alternative approach of using linear cation-exchange gradients combined with RP step gradients was also investigated. Besides the attractive forces, the ionic repulsion contributed to the retention mechanism. The analytes with strong negatively charged sites (phosphorylated peptides, sialylated glycopeptides) eluted in significantly different patterns than generic tryptic peptides. This retention mechanism was employed for the isolation of phosphopeptides or sialylated glycopeptides from non-functionalized peptide mixtures. The mixed-mode column was utilized in conjunction with a phosphopeptide enrichment solid phase extraction (SPE) device packed with metal oxide affinity chromatography (MOAC) sorbent. The combination of MOAC and mixed-mode chromatography (MMC) provided for an enhanced extraction selectivity of phosphopeptides and sialylated glycopeptides peptides from complex samples, such as yeast and human serum tryptic digests.

Enzyme-friendly, mass spectrometry-compatible surfactant for in-solution enzymatic digestion of proteins.

Improved in-solution tryptic digestion of proteins in terms of speed and peptide coverage was achieved with the aid of a novel acid-labile anionic surfactant (ALS). Unlike SDS, ALS solubilizes proteins without inhibiting trypsin or other common endopeptidases activity. Trypsin activity was evaluated in the presence of various denaturants; little or no decrease in proteolytic activity was observed in 0.1-1% ALS solutions (w/v). Sample preparation prior to mass spectrometry and liquid chromatography analysis consists of sample acidification. ALS degrades rapidly at low-pH conditions, which eliminates surfactant-caused interference with analysis. Described methodology combines the advantages of protein solubilization, rapid digestion, high peptide coverages, and easy sample preparation for mass spectrometry and liquid chromatography analyses.

Mechanistic study of stereoselective gas-phase reactions of phosphenium ions with cis- and trans-1,2-diaminocyclohexanes.

The 1,3-dioxolane-2-phosphenium ion, 1,3-benzodioxole-2-phosphenium ion, and o-biphenylenephosphenium ion are reported to react in a stereoselective manner with cis- and trans-1,2-diaminocyclohexanes in the gas phase in a Fourier transform ion cyclotron resonance mass spectrometer. Elimination of NH3 from an addition product was observed only for the trans isomer. Several reaction mechanisms were experimentally and computationally examined (B3LYP/6-31G(d)//HF/6-31G(d) + ZPVE level of theory). The most plausible mechanism is initiated by addition of one of the amino groups to the electrophilic phosphorus atom followed by proton transfer between the amino groups. A change to a diaxial conformation for the trans isomer facilitates anchimeric assistance by the now nucleophilic phosphorus atom as the C-N bond breaks to release NH3. Intramolecular proton transfer competes with the conformational change and ultimately leads to ethylene glycol elimination. The transition states for the critical steps of these two reactions are calculated to be nearly equal in magnitude, which rationalizes the observation of both reactions for the trans-diamine. In contrast, the adduct of the cis isomer can eliminate NH3 via a concerted 1,2-hydride shift without a need for a conformational change. However, the barrier associated with this reaction was found to be substantially greater than for proton transfer between the N- and O-atoms. The latter reaction dominates and ultimately leads to ethylene glycol elimination.