Performance of Metagenomic Next-Generation Sequencing of Cell-Free DNA From Vitreous and Aqueous Humor for Diagnoses of Intraocular Infections.

BACKGROUND: Delayed diagnosis and improper therapy for intraocular infections usually result in poor prognosis. Due to limitations of conventional culture and polymerase chain reaction methods, most causative pathogens cannot be identified from vitreous humor (VH) or aqueous humor (AH) samples with limited volume. METHODS: Patients with suspected intraocular infections were enrolled from January 2019 to August 2021. Metagenomic next-generation sequencing (mNGS) was used to detected causative pathogens. RESULTS: This multicenter prospective study enrolled 488 patients, from whom VH (152) and AH (336) samples were respectively collected and analyzed using mNGS of cell-free DNA (cfDNA). Taking final comprehensive clinical diagnosis as the gold standard, there were 39 patients with indefinite final diagnoses, whereas 288 and 161 patients were diagnosed as definite infectious and noninfectious diseases, respectively. Based on clinical adjudication, the sensitivity (92.2%) and total coincidence rate (81.3%) of mNGS using VH samples were slightly higher than those of mNGS using AH samples (85.4% and 75.4%, respectively). CONCLUSIONS: Using mNGS of cfDNA, an era with clinical experience for more rapid, independent, and impartial diagnosis of bacterial and other intraocular infections can be expected.

A Novel CCK Receptor GPR173 Mediates Potentiation of GABAergic Inhibition.

Cholecystokinin (CCK) enables excitatory circuit long-term potentiation (LTP). Here, we investigated its involvement in the enhancement of inhibitory synapses. Activation of GABA neurons suppressed neuronal responses in the neocortex to a forthcoming auditory stimulus in mice of both sexes. High-frequency laser stimulation (HFLS) of GABAergic neurons potentiated this suppression. HFLS of CCK interneurons could induce the LTP of their inhibition toward pyramidal neurons. This potentiation was abolished in CCK knock-out mice but intact in mice with both CCK1R and 2R knockout of both sexes. Next, we combined bioinformatics analysis, multiple unbiased cell-based assays, and histology examinations to identify a novel CCK receptor, GPR173. We propose GPR173 as CCK3R, which mediates the relationship between cortical CCK interneuron signaling and inhibitory LTP in the mice of either sex. Thus, GPR173 might represent a promising therapeutic target for brain disorders related to excitation and inhibition imbalance in the cortex.SIGNIFICANCE STATEMENT CCK, the most abundant and widely distributed neuropeptide in the CNS, colocalizes with many neurotransmitters and modulators. GABA is one of the important inhibitory neurotransmitters, and much evidence shows that CCK may be involved in modulating GABA signaling in many brain areas. However, the role of CCK-GABA neurons in the cortical microcircuits is still unclear. We identified a novel CCK receptor, GPR173, localized in the CCK-GABA synapses and mediated the enhancement of the GABA inhibition effect, which might represent a promising therapeutic target for brain disorders related to excitation and inhibition imbalance in the cortex.

A study of the pesticide residues in rapeseeds in China: Levels, distribution and health risk assessment.

The aim of this survey was to evaluate the residue levels, distribution and exposure risk of the 38 most commonly used pesticides in rapeseed samples collected from the main production areas in China over a two-year period. The sampling area covered 12 provinces, including Guizhou, Shaanxi, Yunnan, Hunan, Jiangxi, Sichuan, Chongqing, Anhui, Henan, Hubei, Zhejiang, and Jiangsu provinces. The pesticide residues were determined using a QuEChERS (Quick Easy Cheap Effective Rugged and Safe) method coupled with gas chromatography-tandem mass spectrometry and liquid chromatography-tandem mass spectrometry. 8.4% of the rapeseed samples contained pesticides with a residue level ranging from 0.001 to 0.634 mg/kg. The detected analytes were imidacloprid, quizalofop-P-ethyl, thiamethoxam, paclobutrazol, prochloraz, tebuconazole, difenoconazole, s-metolachlor, carbofuran, and carbendazim. The concentrations of four analytes, including thiamethoxam, difenoconazole, carbendazim and prochloraz, exceeded the maximum residue level set by the Chinese government for rapeseed, with exceedance rates of 0.1%, 0.1%, 0.1%, and 1.1%, respectively. Based on the index of quality for residues (IqR) values, 91.6% of the total rapeseed samples had an IqR category of Excellent (IqR = 0). Only 1.5% of the tested samples were of inadequate quality. Furthermore, the assessment of chronic and acute exposure, as well as health risks associated with pesticide residues in rapeseed, was conducted for different age groups within the Chinese population, including adults (6-14 years), children (15-49 years), and the elderly (50-74 years). The results of this assessment indicated that pesticide residues in rapeseed cultivated in China are not expected to be of short- or long-term risks to the Chinese customers.

[Research progress of non-coding RNA involved in glycolysis regulation of hepatocellular carcinoma].

Liver cancer is a common tumor of digestive system. Hepatocellular carcinoma (HCC) is a common type of liver cancer, which has a high degree of malignancy and ranks among the top causes of cancer-related death in the world. Metabolic reprogramming is considered to be an important marker of carcinogenesis. Glucose metabolism is one of the main ways for cells to produce energy. Glycolysis, as the basic reaction of glucose metabolism, plays an important role in cell metabolism. Therefore, the regulation of glycolysis is of great significance to the proliferation and evolution of tumors. More and more non-coding RNAs (ncRNA) have been proved to play an important role in the regulation of tumor glycolysis. This article reviews the role of ncRNA in the regulation of HCC glycolysis and its related mechanisms. At the same time, the prospect of targeted therapy for HCC based on the related mechanisms of glycolysis regulation is put forward.

Genetic characteristics of classical astroviruses in Shenzhen, China, 2016-2019.

Human astrovirus (HAstV) is a single-stranded, positive-sense RNA virus and is the leading cause of viral gastroenteritis. However, despite its prevalence, astroviruses still remain one of the least studied enteroviruses. In this study, we sequenced 11 classical astrovirus strains from clinical samples collected in Shenzhen, China from 2016 to 2019, analyzed their genetic characteristics, and deposited them into GenBank. We conducted phylogenetic analysis using IQ-TREE software, with references to astrovirus sequences worldwide. The phylogeographic analysis was performed using the Bayesian Evolutionary Analysis Sampling Trees program, through Bayesian Markov Chain Monte Carlo sampling. We also conducted recombination analysis with the Recombination Detection Program. The newly sequenced strains were categorized as HAstV genotype 1, which is the predominant genotype in Shenzhen. Phylogeographic reconstruction indicated that HAstV-1 may have migrated from the United States to China, followed by frequent transmission between China and Japan. The recombination analysis revealed recombination events within and across genotypes, and identified a recombination-prone region that produced relatively uniform recombination breakpoints and fragment lengths. The genetic analysis of HAstV strains in Shenzhen addresses the current lack of astrovirus data in the region of Shenzhen and provides key insights to the evolution and transmission of astroviruses worldwide. These findings highlight the importance of improving surveillance of astroviruses.

Umbrella-frame silicon nanorod arrays decorated with Au nanoparticles as recyclable SERS substrates.

Surface-enhanced Raman scattering (SERS) is a powerful technique for detection and identification of trace amounts of molecules with high specificity. A variety of two- and three-dimensional (3D) SERS substrates have been developed. Among these SERS substrates, to further develop new morphology of 3D SERS-active substrate with robust SERS functionality is still desired and necessary. In this paper, what we believe to be a novel and effective SERS-active substrate based on large-scale 3D Si hierarchical nanoarrays in conjunction with homogeneous Au nanoparticles (AuNPs) was proposed. Its building block shaped like the umbrella-frame structure was fabricated by a simple and cost-effective top-down nanofabrication method. Such umbrella-frame structure achieved excellent SERS performance with high sensitivity and spatial uniformity. For R6G molecules, the detection limit can be as low as 10-14 M, with an enhancement factor of up to 107. The relative standard deviation can reach about 11% above 30 positions across an area of 100×100 µm2. This is mainly attributed to much more active-sites provided by the umbrella-frame structure for adsorption of target molecules and AuNPs, and sufficient 3D hotspots generated by the coupling between the SiNRs guided mode and AuNPs localized surface plasmon resonance (LSPR), as well as that between AuNPs LSPR. Especially by introducing the umbrella-ribs SiNRs and AuNPs, the light field can be greatly confined to the structure surface, creating strongly enhanced and even zero-gap fields in 3D space. Moreover, the proposed SERS-active substrate can be erased and reused multiple times by plasma cleaning and exhibits typically excellent recyclability and stability for robust SERS activity. The experimental results demonstrate the proposed substrate may serve as a promising SERS platform for trace detection of chemical and biological molecules.

NIR-II fluorescent Ag2Se polystyrene beads in a lateral flow immunoassay to detect biomarkers for breast cancer.

Fluorescent lateral flow immunoassay (LFA), one tool in point of care testing (POCT) systems for breast cancer, has attracted attention because it is quick, simple, and convenient. However, samples and the constituent material exhibit autofluorescence in the visible region, which is a very large obstacle in the development of fluorescent LFAs. The autofluorescence of biological samples is scarcely found in the second near-infrared (NIR-II) range and samples scatter and absorb less NIR-II light than visible light. Here, we report an NIR-II QD-LFA platform using the NIR-II fluorescent Ag2Se quantum dots (QDs) with 1020 nm emission encapsulated into polystyrene beads as fluorescent probes. The NIR-II LFA platform was established to detect breast cancer tumour markers (CEA and CA153) within 15 min with a low limit of detection (CEA: 0.768 ng mL-1, CA153: 1.192 U mL-1), high recoveries (93.7% ~ 108.8%), and relative standard deviations (RSDs) of less than 10%. This study demonstrated the potential of NIR-II Ag2Se polystyrene beads as a fluorescent probe in LFA for rapid and accurate identification of biomarkers. They are suited for use in professional situations.

Water-in-Oil Pickering Emulsions Stabilized by Hydrophobized Protein Microspheres.

Water-in-oil (w/o) Pickering emulsions have gained considerable attention in colloid science and daily applications. However, for the formation of w/o emulsions, especially those with high internal water content, the particulate stabilizers are required to be sufficiently hydrophobic, and synthetic or chemically modified particles have been mostly reported until now, which are not biocompatible and sustainable. We present a zein protein-based microsphere derived from the Pickering emulsion template, in which protein microspheres are feasibly in situ hydrophobized by silica nanoparticles, enabling the stabilization of w/o Pickering emulsions. The effects of microsphere concentration, water/oil volume ratio, oil types, and pH on the stabilization of prepared w/o emulsions are systematically studied, revealing prominent characteristics of the controllable size, high water fraction, universal adaptation of oils, as well as broad pH stability. As a demonstration, the Pickering emulsion effectively encapsulates vitamin C and shows high stability for long storage duration against ultraviolet radiation/heat. Therefore, this novel proteinaceous particle-stabilized w/o Pickering emulsion has great potential in the delivery and protection of water-soluble bioactive substrates.

VALUABLE APPLICATION OF THE ß- d -GLUCAN TESTING OF INTRAOCULAR FLUID FOR THE DIAGNOSIS OF FUNGAL ENDOPHTHALMITIS.

PURPOSE: To evaluate the value of the ß- d -glucan (BDG) testing of intraocular fluid for the diagnosis of fungal endophthalmitis (FE). METHODS: Twenty patients (22 eyes) with FE were diagnosed using both culture and nonculture methods. Intraocular fluid was collected for BDG testing, including 22 eyes of FE and 55 eyes of control group. Under different BDG cutoff points as the test-positives, the BDG sensitivity, specificity, positive predictive value, and negative predictive value for FE were analyzed. RESULTS: The BDG testing value was 1,022.78 ± 1,362.40 pg/mL in the FE group, significantly higher than that of the control group (105.0 ± 180.80 pg/mL, P < 0.001). The area under the receiver operating characteristic (ROC) curve was 0.885 (95% confidence interval, 0.793-0.978; P < 0.001). With the prespecified BDG cutoff 107.83 pg/ml as the test-positive, sensitivity was 81.8%, specificity was 87.5%, and the Youden index was 0.693. When the BDG cutoff was depicted as 202.05 pg/mL, sensitivity reduced to 77.3%, specificity increased at 95.8%, and the Youden index reached the highest value of 0.731. CONCLUSIONS: ß- d -glucan testing of intraocular fluid demonstrated good sensitivity and specificity regarding the diagnosis of FE, which can provide earlier diagnosis to achieve better outcomes.

Serum neuron-specific enolase, magnetic resonance imaging, and electrophysiology for predicting neurodevelopmental outcomes of neonates with hypoxic-ischemic encephalopathy: a prospective study.

BACKGROUND: Neonatal hypoxic-ischemic encephalopathy (HIE) is an important cause of mortality and morbidity. Effective indicators for the early diagnosis of brain injury after HIE and prognosis are lacking. This study aimed to examine the predictive value of serum neuron-specific enolase (NSE), amplitude-integrated electroencephalography (aEEG), and magnetic resonance imaging (MRI), alone and in combination, for the neurological outcomes in neonates with HIE. METHODS: Newborns with HIE born and treated at the Third Affiliated Hospital of An-Hui Medical University were consecutively included in this prospective cohort study (June 2013 to December 2020). Encephalopathy was classified as mild, moderate or severe according to Samat and Sarnat. All patients were assessed serum 1-day NSE and 3-day NSE levels after birth. The children were classified by neurological examination and Bayley Scales of Infant Development II at 18 months of age. ROC analysis was used to evaluate the predictive accuracy of the neurodevelopment outcomes. RESULTS: A total of 50 HIE neonates were enrolled (normal group: 32 (64.0%), moderate delay: 5 (10.0%), severe delay: 30(26.0%)) according to Bayley II scores. Serum 3-day NSE levels increased with worsening neurodevelopment outcomes (normal: 20.52 ± 6.42 µg/L vs. moderate: 39.82 ± 5.92 µg/L vs. severe: 44.60 ± 9.01 µg/L, P < 0.001). The MRI findings at 4-7 days after birth were significantly different among the three groups (P < 0.001). Forty-two (84.0%) children had abnormal aEEG. The combination of the three abnormalities combined together had 100% sensitivity, 97.70% specificity, 98.25% PPV, and 99.98% NPV. CONCLUSIONS: MRI, aEEG, and 3-day NSE can predict the neurological prognosis of newborns with HIE without hypothermia treatment. Their combination can improve the predictive ability for long-term neurobehavioral prognosis.

The Protective Role of Apelin in the Early Stages of Diabetic Retinopathy.

Diabetic retinopathy (DR) is one of the most common and serious microvascular complications of diabetes. Although current treatments can control the progression of DR to a certain extent, there is no effective treatment for early DR. Apart from vascular endothelial growth factor, it has been noted that the apelin/APJ system contributes to the pathogenesis of DR. We used a high-fat diet/streptozotocin-induced type 2 diabetic mouse model. The mice were divided into a lentivirus control group (LV-EGFP), an apelin-overexpression group (LV-Apelin+), and an apelin-knockdown group (LV-Apelin-), all of which were administrated intravitreal injections. LV-Apelin+ ameliorated the loss of pericytes in DR mice, whereas LV-Apelin- aggravated the loss of pericytes. Similarly, LV-Apelin+ reduced the leakage of retinal vessels, whereas LV-Apelin- exacerbated it. The genes and signaling pathway related to cell adhesion molecules were downregulated, whereas the cell-cell tight junctions and anti-apoptotic genes were upregulated in response to apelin overexpression. However, the alterations of these same genes and signaling pathways were reversed in the case of apelin knockdown. Additionally, LV-Apelin+ increased ZO-1 and occludin levels, whereas LV-Apelin- decreased them. Our results suggest that apelin can reduce vascular leakage by protecting pericytes, which offers a promising new direction for the early treatment of DR.

Extra-pulmonary vein driver mapping and ablation for persistent atrial fibrillation in obese patients.

AIMS: The aim of this study was to determine whether driver ablation effectively treats persistent atrial fibrillation (AF) in obese patients. METHODS AND RESULTS: We randomly assigned 124 persistent AF obese patients to two groups, one undergoing conventional ablation (n = 62) and the other undergoing driver ablation (n = 62). Sixty-two non-obese patients with persistent AF undergoing driver ablation served as matched controls. Bipolar electrogram dispersion was analysed for driver mapping. Epicardial adipose tissue (EAT) volume was measured using cardiac computed tomography. Obese patients had a higher proportion of driver regions in the posterior wall (56.5% vs. 32.3%, P = 0.007). Driver complexity, measured as the average number and area of driver regions, was higher in the obese group than in the non-obese group (3.5 ± 1.0 vs. 2.9 ± 0.9, P < 0.001; 15.5% ± 4.2% vs. 9.8 ± 2.6%, P < 0.001, respectively). Left atrial EAT volume correlated better with the proportion of area of driver regions than did body mass index (BMI) and total EAT (BMI: r2 = 0.250, P < 0.001; total EAT: r2 = 0.379, P < 0.001; and left atrial EAT: r2 = 0.439, P < 0.001). The rate of AF termination was significantly higher in the driver ablation group than in the conventional ablation group (82.9% vs. 22.8%, P < 0.001). During the follow-up period of 16.9 ± 6.5 months, patients in the driver ablation group had significantly better AF-free survival (91.91% vs. 79.0%, log rank test, P = 0.026) and AF/atrial tachycardia-free survival (83.9% vs. 64.5%, log rank test, P = 0.011) than did patients in the conventional ablation group. CONCLUSION: Obesity is associated with increased driver complexity. Driver ablation improves long-term outcomes in obese patients with persistent AF.

Screening and Characterization of Two Extracellular Polysaccharide-Producing Bacteria from the Biocrust of the Mu Us Desert.

The extracellular polysaccharide (EPS) matrix embedding microbial cells and soil particles plays an important role in the development of biological soil crusts (BSCs), which is widely recognized as beneficial to soil fertility in dryland worldwide. This study examined the EPS-producing bacterial strains YL24-1 and YL24-3 isolated from sandy soil in the Mu Us Desert in Yulin, Shaanxi province, China. The strains YL24-1 and YL24-3 were able to efficiently produce EPS; the levels of EPS were determined to be 257.22 µg/mL and 83.41 µg/mL in cultures grown for 72 h and were identified as Sinorhizobium meliloti and Pedobacter sp., respectively. When the strain YL24-3 was compared to Pedobacter yulinensis YL28-9T using 16S rRNA gene sequencing, the resemblance was 98.6% and the strain was classified as Pedobacter sp. using physiological and biochemical analysis. Furthermore, strain YL24-3 was also identified as a subspecies of Pedobacter yulinensis YL28-9T on the basis of DNA-DNA hybridization and polar lipid analysis compared with YL28-9T. On the basis of the EPS-related genes of relevant strains in the GenBank, several EPS-related genes were cloned and sequenced in the strain YL24-1, including those potentially involved in EPS synthesis, assembly, transport, and secretion. Given the differences of the strains in EPS production, it is possible that the differences in gene sequences result in variations in the enzyme/protein activities for EPS biosynthesis, assembly, transport, and secretion. The results provide preliminary evidence of various contributions of bacterial strains to the formation of EPS matrix in the Mu Us Desert.

MORPHOLOGICAL AND FUNCTIONAL CHARACTERISTICS AT THE ONSET OF EXUDATIVE CONVERSION IN AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To characterize retinal morphology differences among different types of choroidal neovascularization and visual function changes at the onset of exudative age-related macular degeneration. METHODS: In a post hoc analysis of a prospective clinical study, 1,097 fellow eyes from subjects with choroidal neovascularization in the study eye enrolled in the HARBOR trial were evaluated. The onset of exudation was diagnosed on monthly optical coherence tomography by two masked graders. At conversion as well as 1 month earlier, pigment epithelial detachment, intraretinal cystoid fluid, subretinal fluid, subretinal hyperreflective material, as well as ellipsoid zone and external limiting membrane loss were quantitatively analyzed. Hyperreflective foci, retinal pigment epithelial defects, haze and vitreoretinal interface status were evaluated qualitatively. Main outcome measures included visual acuity and rates of morphologic features at conversion and 1 month earlier. RESULTS: New-onset exudation was detected in 92 eyes. One month before conversion, hyperreflective foci, pigment epithelial detachment, retinal pigment epithelial defects, and haze were present in the majority of eyes. At the onset of exudation, the volumes of intraretinal cystoid fluid, subretinal fluid, subretinal hyperreflective material and pigment epithelial detachment, and the areas of external limiting membrane and ellipsoid zone loss significantly increased. The mean vision loss was -2.2 letters. Pathognomonic patterns of the different choroidal neovascularization types were already apparent 1 month before conversion. CONCLUSION: Characteristic choroidal neovascularization-associated morphological changes are preceding disease conversion, while vision loss at the onset of exudation is minimal. Individual lesion types are related to specific changes in optical coherence tomography morphology already before the time of conversion. Our findings may help to elucidate the pathophysiology of neovascular age-related macular degeneration and support the diagnosis of imminent disease conversion.

Cathodic electrodeposited Cu-BTC MOFs assembled from Cu(II) and trimesic acid for electrochemical determination of bisphenol A.

The authors describe a novel electrochemical determination method for bisphenol A (BPA) based on the electrosynthesised Cu-BTC (H3BTC: trimesic acid) films. Using H3BTC as the ligand, Cu(NO3)2 as the precursor of copper ions, and triethylamine hydrochloride (Et3NHCl) as the probase source, Cu-BTC films were directly deposited on glassy carbon electrode (GCE) surface via cathodic electrochemical reduction under -1.30 V. Considering the electrocatalytic activity of metal center Cu2+, Cu-BTC films were applied to construct the electrochemical determination platform for BPA. Chronocoulometry and electrochemical impedance spectroscopy were used to study the signal enhancement mechanism. The determination conditions were optimized. As a result, a sensitive electrochemical method was constructed for BPA. The peak currents, best measured at voltage of 0.496 V vs. SCE (KCl saturated calomel reference electrode), increase linearly in the range from 5.0 to 2000 nM. The value of determination limit is 0.72 nM. The proposed method was successfully applied to determine BPA in spiked urine, spiked waste water samples and plastic products. The results were in good agreement with those obtained for the same samples by high-performance liquid chromatography (HPLC). Graphical abstract Schematics for the construction of electrochemical determination for bisphenol A.

Simultaneous determination for A. flavus-metabolizing mycotoxins by time-resolved fluorescent microbead or gold-enabling test strip in agricultural products based on monoclonal antibodies.

To simultaneously detect two metabolites of Aspergillus flavus, namely, cyclopiazonic acid (CPA) and aflatoxin (AFT), an ultrasensitive monoclonal antibody (mAb) YTT-2 against CPA was developed and characterized, with sensitivity to CPA of 1.32 ng mL-1. Along with the previously homemade mAb 1C11 against AFT, two mAbs were used to develop time-resolved fluorescence immunoprobes or gold immunoprobes. We developed two multiple-analyte paper immunosensors including time-resolved fluorescent immunochromatographic assay (TRFICA) and gold immunochromatographic assay (GICA) for the simultaneous determination of CPA and AFT. The TRFICA showed limits of determination (LODs) of 0.21 and 0.004 ng mL-1, while the GICA showed LODs of 0.33 and 0.01 ng mL-1 for CPA and AFT, respectively. To validate the specificity of the two rapid immunoassays, rice, corn and peanut samples were spiked with different concentrations of CPA and AFT. The two methods showed satisfactory recoveries (76.39~90.82% for CPA and 84.60~94.45% for AFT) and coefficients of variation of 3.50~7.80% for CPA and 4.12~13.90% for AFT. The results indicated that the TRFICA could complete the test within 5 min and had lower LODs and linear ranges, compared with that of GICA. The method developed in this work can be widely applied to the rapid and quantitative simultaneous determination of multiple harmful metabolites in fungi for food safety and health care. Graphical abstract.

Robust DNA-Bridged Memristor for Textile Chips.

Electronic textiles may revolutionize many fields, such as communication, health care and artificial intelligence. To date, unfortunately, computing with them is not yet possible. Memristors are compatible with the interwoven structure and manufacturing process in textiles because of its two-terminal crossbar configuration. However, it remains a challenge to realize textile memristors owing to the difficulties in designing advanced memristive materials and achieving high-quality active layers on fiber electrodes. Herein we report a robust textile memristor based on an electrophoretic-deposited active layer of deoxyribonucleic acid (DNA) on fiber electrodes. The unique architecture and orientation of DNA molecules with the incorporation of Ag nanoparticles offer the best-in-class performances, e.g., both ultra-low operation voltage of 0.3 V and power consumption of 100 pW and high switching speed of 20 ns. Fundamental logic calculations such as implication and NAND are demonstrated as functions of textile chips, and it has been thus integrated with power-supplying and light emitting modules to demonstrate an all-fabric information processing system.

Screening a fosmid library of Xenorhabdus stockiae HN_xs01 reveals SrfABC toxin that exhibits both cytotoxicity and injectable insecticidal activity.

Xenorhabdus spp., entomopathogenic bacteria symbiotically associated with the nematodes of the Steinernematid family, are known to produce several toxic proteins that interfere with the cellular immune responses of insects. In order to identify novel cytotoxins from Xenorhabdus spp., a fosmid library of X. stockiae HN_xs01 strain was constructed and the cytotoxicity of fosmid clones was tested against insect midgut CF-203 cells. An FS2 clone bearing the srfABC operon, originally identified in Salmonella enterica, exhibited excellent cytotoxicity against CF-203 cells. The srfABC operon alone exhibited cytotoxic effects and all three components of SrfABC toxin were essential for full cytotoxicity. Immunofluorescence studies showed that SrfABC toxin could depolymerize microtubules and disrupt mitochrondria. Flow cytometer analysis demonstrated that SrfABC toxin significantly induced G2/M phase arrest and apoptosis in CF-203 cells. Furthermore, SrfABC toxin exhibits highly injectable insecticidal activity against Helicoverpa armigera larvae. As is often found in host-associated microorganisms, SrfABC toxin is thought to play an important role in host colonization.

Directly probing the dissociation effects of graphene oxide nanosheets on hIAPP fibrils.

The aggregation of human islet amyloid polypeptides (hIAPP) to mature fibrils is considered as the main cause of type II diabetes. Therefore destroying the pre-formed hIAPP fibrils is expected to be a promising strategy for therapeutic treatments. In this work, the dissociation effects of graphene oxide (GO) nanosheets on hIAPP mature fibrils are investigated. The results clearly demonstrate that hIAPP fibrils can be quickly adsorbed on the GO surface and efficiently broken into short fragments. Meanwhile, the ß-sheet structures of hIAPP fibrils are greatly destroyed. Particularly, in situ atomic force microscopy was applied to monitor the real-time interaction between hIAPP fibrils and GO nanosheets. It provides distinct evidence that the disruption of hIAPP fibrils by GO nanosheets mainly occurs at the GO edges. Size-dependent experiments further justify the interfere of edge contribution, which suggest small-sized GO nanosheets exhibit better dissociation ability than large-sized ones. Therefore, this study not only provides valuable information that GO nanosheets (especially small-sized ones) can act as efficient nanoblades to break hIAPP fibrils, but also suggests a powerful and widely available methodology for investigating real-time interaction between nanomaterials and biomolecules.

Integrated analysis of differentially expressed lncRNAs in Medial Temporal Lobe Epilepsy.

BACKGROUND: Medial temporal lobe epilepsy (MTLE) is the most frequent type of epilepsy. In recent years, the important roles of lncRNAs in regulating human diseases progression had been implicated, including in epilepsy. However, comprehensive analysis of differentially expressed lncRNAs in Medial Temporal Lobe Epilepsy was still lacking. OBJECTIVES: The aim of this study was to explore relevant lncRNAs in MTLE. METHODS: In present study, we analyzed a public dataset GSE25453 to identify differentially expressed lncRNAs and mRNAs in the MTLE. RESULTS: A total of 16 lncRNAs (C6orf176, NCRNA00259, PRO1768, TTTY11, LOC149620, GDEP, LOC400891, HLA-DRB6, TTTY21, TTTY3, NBR2, TTTY1, FAM183B, C15orf51, FAM74A3, and MALAT1) were identified. LncRNA co-expression network analysis showed these lncRNAs were mainly enriched in regulating transcription, inflammatory response, DNA binding, Jak Stat Signaling Pathway, and Mapk Signaling Pathway. Meanwhile, lncRNA-mRNA-biological processes networks were also performed to evaluate the potential roles of key lncRNAs in MTLE. CONCLUSIONS: This study will be useful to explore the potential candidate biomarkers for diagnosis, prognosis, and drug targets of MTLE.