ExoSloNano: Multi-Modal Nanogold Tags for identification of Macromolecules in Live Cells & Cryo-Electron Tomograms.

In situ cryo-Electron Microscopy (cryo-EM) enables the direct interrogation of structure-function relationships by resolving macromolecular structures in their native cellular environment. Tremendous progress in sample preparation, imaging and data processing over the past decade has contributed to the identification and determination of large biomolecular complexes. However, the majority of proteins are of a size that still eludes identification in cellular cryo-EM data, and most proteins exist in low copy numbers. Therefore, novel tools are needed for cryo-EM to identify the vast majority of macromolecules across multiple size scales (from microns to nanometers). Here, we introduce and validate novel nanogold probes that enable the detection of specific proteins using cryo-ET (cryo-Electron Tomography) and resin-embedded correlated light and electron microscopy (CLEM). We demonstrate that these nanogold probes can be introduced into live cells, in a manner that preserves intact molecular networks and cell viability. We use this system to identify both cytoplasmic and nuclear proteins by room temperature EM, and resolve associated structures by cryo-ET. We further employ gold particles of different sizes to enable future multiplexed labeling and structural analysis. By providing high efficiency protein labeling in live cells and molecular specificity within cryo-ET tomograms, we establish a broadly enabling tool that significantly expands the proteome available to electron microscopy.

PI4P-mediated solid-like Merlin condensates orchestrate Hippo pathway regulation.

Despite recent studies implicating liquid-like biomolecular condensates in diverse cellular processes, many biomolecular condensates exist in a solid-like state, and their function and regulation are less understood. We show that the tumor suppressor Merlin, an upstream regulator of the Hippo pathway, localizes to both cell junctions and medial apical cortex in Drosophila epithelia, with the latter forming solid-like condensates that activate Hippo signaling. Merlin condensation required phosphatidylinositol-4-phosphate (PI4P)-mediated plasma membrane targeting and was antagonistically controlled by Pez and cytoskeletal tension through plasma membrane PI4P regulation. The solid-like material properties of Merlin condensates are essential for physiological function and protect the condensates against external perturbations. Collectively, these findings uncover an essential role for solid-like condensates in normal physiology and reveal regulatory mechanisms for their formation and disassembly.

Recent Advances in the Application of Natural Products for Postharvest Edible Mushroom Quality Preservation.

Edible mushrooms are favored by consumers for their excellent nutritional value and pharmacological properties. However, fresh mushrooms are highly perishable and undergo rapid quality deterioration induced by a series of intrinsic and extrinsic factors during postharvest storage. In recent years, the application of natural products derived from plants, animals, microorganisms, and other sources in mushroom quality preservation has drawn increasing attention. Compared to chemical preservatives, natural products show similar or higher biological activity and have few side effects on human health. This review summarizes the recent advances in the application of natural products used for quality maintenance of postharvest mushrooms. These natural substances mainly include essential oils, polyphenols, polysaccharides, bacteriocins, and other extracts. They have the potential to inhibit mushroom weight loss, softening, and browning, reduce the count of pathogenic microorganisms, and retain nutrients and flavor, effectively improving the quality of mushrooms and extending their shelf-life. The preservation techniques for natural products and their preservation mechanisms are also discussed here. Overall, this review provides current knowledge about natural products in edible mushroom preservation and aims to inspire more in-depth theoretical research and promote further practical application.

Synchronous reducing anti-nutritional factors and enhancing biological activity of soybean by the fermentation of edible fungus Auricularia auricula.

Auricularia auricula fermentation was performed to reduce anti-nutritional factors, improve nutritional components, and enhance biological activity of soybean. Results showed that the contents of raffinose, stachyose, and trypsin inhibitor were significantly decreased from initial 1.65 g L-1, 1.60 g L-1, and 284.67 µg g-1 to 0.14 g L-1, 0.35 g L-1, and 4.52 µg g-1 after 144 h of fermentation, respectively. Simultaneously, the contents of polysaccharide, total phenolics, and total flavonoids were increased, and melanin was secreted. The isoflavone glycosides were converted to their aglycones, and the contents of glyctin and genistin were decreased from initial 1107.99 µg g-1 and 2852.26 µg g-1 to non-detection after 72 h of fermentation, respectively. After 96 h of fermentation, the IC50 values of samples against DPPH and ABTS radicals scavenging were decreased from 17.61 mg mL-1 and 3.43 mg mL-1 to 4.63 mg mL-1 and 0.89 mg mL-1, and those of samples inhibiting α-glucosidase and angiotensin I-converting enzyme were decreased from 53.89 mg mL-1 and 11.27 mg mL-1 to 18.24 mg mL-1 and 6.78 mg mL-1, respectively, indicating the significant increase in these bioactivities. These results suggested A. auricula fermentation can enhance the nutritional quality and biological activity of soybean, and the fermented soybean products have the potential to be processed into health foods/food additives.

Enhancement of anti-diabetic activity of pomelo peel by the fermentation of Aspergillus oryzae CGMCC23295: In vitro and in silico docking studies.

In this work, pomelo peel was fermented by Aspergillus oryzae CGMCC23295 to enhance its anti-diabetic properties. Results showed the total phenolic and flavonoids contents, ferric reducing antioxidant power (FRAP), scavenging capacities against 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals, as well as inhibitory abilities against α-amylase and α-glucosidase of pomelo peel were increased and fermentation for 8 days was the best. Additionally, the fermented sample could also enhance the glucose consumption and glycogen of HepG2 cell. Based on UPLC-MS/MS analysis, binding energy calculation, concentration determination and IC50 measurement, purpurin, apigenin, genistein, and paxilline could be concluded to be the main compounds to enhance the inhibition activities of fermented sample against α-amylase and α-glucosidase. Furthermore, computational studies were performed to reveal the the binding site and molecular interactions between paxilline and α-amylase, as well as purpurin and α-glucosidase. These findings provide a base for the utilization and valorization of pomelo peels as functional food additives by fermentation.

Cigarette smoke triggers calcium overload in mouse hippocampal neurons via the ΔFOSB-CACNA2D1 axis to impair cognitive performance.

A growing body of evidence shows that cigarette smoking impairs cognitive performance. The 'Calcium Hypothesis' theory of neuronopathies reveals a critical role of aberrant calcium signaling in compromised cognitive functions. However, the underlying implications of abnormalities in calcium signaling in the neurotoxicity induced by cigarette smoke (CS) have not yet been identified. CACNA2D1, an important auxiliary subunit involved in the composition of voltage-gated calcium channels (VGCCs), was reported to affect the calcium signaling in neurons by facilitating VGCCs-mediated Ca2+ influx. ΔFOSB, an alternatively-spliced product of the Fosb gene, is an activity-dependent transcription factor induced robustly in the brain in response to environmental stimuli such as CS. Interestingly, our preliminary bioinformatics analysis revealed a significant co-expression between ΔFOSB and CACNA2D1 in brain tissues of patients with neurodegenerative diseases characterized by progressive cognitive decline. Therefore, we hypothesized that the activation of the ΔFOSB-CACNA2D1 axis in response to CS exposure might cause dysregulation of calcium homeostasis in hippocampal neurons via VGCCs-mediated Ca2+ influx, thereby contributing to cognitive deficits. To this end, the present study established a CS-induced mouse model of hippocampus-dependent cognitive impairment, in which the activation of the ΔFOSB-CACNA2D1 axis accompanied by severe calcium overload was observed in the mouse hippocampal tissues. More importantly, ΔFOSB knockdown-/overexpression-mediated inactivation/activation of the ΔFOSB-CACNA2D1 axis interdicted/mimicked CS-induced dysregulation of calcium homeostasis followed by severe cellular damage in HT22 mouse hippocampal neurons. Mechanistically speaking, a further ChIP-qPCR assay confirmed the physical interaction between transcription factor ΔFOSB and the Cacna2d1 gene promoter, suggesting a direct transcriptional regulation of the Cacna2d1 gene by ΔFOSB. Overall, our current work aims to deliver a unique insight into the neurotoxic mechanisms induced by CS to explore potential targets for intervention.

Adjuvant chemotherapy benefits on patients with elevated carcinoembryonic antigen in stage IIA colon cancer: a SEER-based analysis.

OBJECTIVE: Indications for adjuvant chemotherapy in stage IIA (T3N0M0) colon cancer are still controversial. The purpose of this study was to evaluate the prognostic value of elevated carcinoembryonic antigen (CEA) levels for cancer-specific survival (CSS) and overall survival (OS) in patients with stage IIA colon cancer. We aimed to examine the impact of adjuvant chemotherapy on OS in stage IIA colon cancer patients with elevated CEA levels. METHODS: Patients with stage IIA colon cancer (N = 3477) diagnosed between 2010 and 2015 were identified using the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier and Cox proportional hazards regression models were used to assess the prognostic effect of CEA on CSS and OS. RESULTS: Cox regression analysis demonstrated that CEA was an independent risk factor for CSS and OS in patients with stage IIA colon cancer (CSS: HR = 2.001, 95% CI 1.603-2.499, P < 0.001; OS: HR = 1.530, 95% CI 1.335-1.752, P < 0.001). In the subgroup with elevated CEA, patients received adjuvant chemotherapy had a better OS compared with those did not (χ2 = 10.585, p = 0.001). CONCLUSION: CEA was an independent risk factor for CSS and OS in patients with stage IIA colon cancer. Patients with stage IIA colon cancer with an elevated CEA level might benefit from adjuvant chemotherapy.

Childhood emotional abuse and motor impulsiveness among male violent inmates with antisocial personality disorder.

This study aimed to explore the relationship among childhood maltreatment, impulsiveness and antisocial personality through a questionnaire survey of violent male inmates. We found that the scores of inmates with Antisocial Personality Disorder (ASPD) in Childhood Trauma Questionnaire-28 item Short Form (CTQ-SF) and Barratt Impulsive Scale-11 (BIS-11) were higher than those in the Non-Antisocial personality group, and there was a significant correlation between the scores of CTQ-SF and BIS-11. We found that the interaction between impulsivity and childhood abuse predicts ASPD levels. Moreover, motor and non-planning impulsiveness played important roles in the observed differences in antisocial personality scores among the inmates who had experienced childhood maltreatment; motor impulsiveness was mainly related to emotional abuse, physical abuse, and sexual abuse, while non-planning impulsiveness was mainly related to emotional neglect and physical neglect. These findings suggest that identifying and providing timely intervention for inmates with high impulsiveness who experienced maltreatment in childhood may also contribute to the prevention of violent behavior and to better prison management.

Latitudinal Variation in the Pattern of Temperature-Dependent Sex Determination in the Japanese Gecko, Gekko japonicus.

Identifying latitudinal variation in the pattern of temperature-dependent sex determination (TSD) may provide insight into the evolution of sex determining system in vertebrates, but such studies remain limited. Here, we quantified TSD patterns of three geographically separated populations of the Japanese gecko (Gekko japonicus) along the latitudinal cline of China. We incubated gecko eggs from the three populations at constant temperatures of 24, 26, 28, 30, and 32 °C to quantify the TSD pattern. Our study demonstrated that G. japonicus exhibited a FMF pattern of TSD, with the low and high incubation temperatures yielding significantly female-biased hatchlings, and the medium temperatures producing male-biased hatchlings. More interestingly, we found latitudinal variations in the TSD pattern in terms of pivotal temperatures (Tpivs), transitional range of temperatures (TRT), and the sex ratios at the medium temperatures. The Tpivs for the low-latitude population were lower than those for the two high-latitude populations. The low-latitude population has a narrower FM TRT, but a wider MF TRT. The sex ratio is almost 50:50 for the low-latitude population when eggs were incubated from 26 to 30 °C. Conversely, the sex ratio is male-biased for the two high-latitude populations at 28 or 30 °C. Therefore, G. japonicus may provide an interesting system to explore the evolution of TSD in reptiles given the diversity of TSD patterns among populations.

Physicochemical characterization, adsorption function and prebiotic effect of chitin-glucan complex from mushroom Coprinus comatus.

Chitin-glucan complex (CGC) is a novel insoluble dietary fiber with multiple physiological activities. In this work, CGC was extracted from the fruiting body of Coprinus comatus and its physicochemical properties and prebiotic effects were investigated. The results indicated that CGC consisted of glucosamine and glucose in a molar ratio of 67: 33 with degree of acetylation of 61.91% and crystallinity index of 25.40%. The maximum degradation temperature was determined to be 307.52 °C, and a woven fibrous structure was observed by scanning electron microscopy. CGC exhibited higher oil-holding capacity, water-holding capacity and nitrite ion adsorption capacity than commercial chitin, and showed potential prebiotic effects. Compared with control and commercial chitin, CGC significantly (P < 0.05) increased the concentration of propionic and butyric acids. These results suggested that CGC from C. comatus was promising to be an alternative source of CGC products and used as a bioactive ingredient in functional foods.

Photoinduced Multi-Bit Nonvolatile Memory Based on a van der Waals Heterostructure with a 2D-Perovskite Floating Gate.

The development of floating-gate nonvolatile memory (FGNVM) is limited by the charge storage, retention and transfer ability of the charge-trapping layer. Here, it is demonstrated that due to the unique alternate inorganic/organic chain structure and superior optical sensitivity, an insulating 2D Ruddlesden-Popper perovskite (2D-RPP) layer can function both as an excellent charge-storage layer and a photosensitive layer. Optoelectronic memory composed of a MoS2 /hBN/2D-RPP (MBR) van der Waals heterostructure is demonstrated. The MBR device exhibits unique light-controlled charge-storage characteristics, with maximum memory window up to 92 V, high on/off ratio of 104 , negligible degeneration over 103  s, >1000 program/erase cycles, and write speed of 500 µs. Dependent on the initial states, the MBR optoelectronic memory can be programmed in both positive photoconductivity (PPC) and negative photoconductivity (NPC) modes, with up to 11 and 22 distinct resistance states, respectively. The optical program power for each bit is as low as 36/10 pJ for PPC/NPC. The results not only reveal the potential of 2D-RPP as a superior charge-storage medium in floating-gate memory, but also provides an effective strategy toward fast, low-power and stable optical multi-bit storage and neuromorphic computing.

Proteomics Reveals the Mechanism Underlying the Autolysis of Postharvest Coprinus comatus Fruiting Bodies.

Autolysis occurs widely in edible mushroom fruiting bodies after harvest, but the mechanism is still unclear. In this study, quantitative proteomics and bioinformatics analyses have been applied for revealing the autolysis mechanism of postharvest Coprinus comatus fruiting bodies. The results indicated that the autolysis mechanism of postharvest C. comatus was complicated. Before pileus opening, the carbohydrate metabolism including cell wall hydrolysis and energy biosynthesis, which were probably regulated by the ribosome, was involved in mushroom autolysis, whereas after pileus opening, the autolysis mechanism was related to the accumulated reactive oxygen species (ROS) and activated mitogen-activated protein kinase (MAPK) signaling pathway based on the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Furthermore, the changes in cell wall components and hydrolases, along with the production of ROS and the activities of oxidoreductase in C. comatus, were also verified to confirm the proteomic analysis results.

Van der Waals MoS2/Two-Dimensional Perovskite Heterostructure for Sensitive and Ultrafast Sub-Band-Gap Photodetection.

Two-dimensional (2D) hybrid perovskites have been extensively studied as the promising light-sensitive materials in the photodetectors owing to their improved structural stability over that of their three-dimensional counterparts. However, the application of the 2D perovskite-based photodetector in the near-infrared (NIR) region is obstructed by the large intrinsic optical band gap. Herein, we develop a novel van der Waals heterostructure composed of few-layer 2D perovskite/MoS2 nanoflakes, which exhibits high-sensitivity detection performance over a broad spectral region, from the visible region to the telecommunication wavelength (i.e., 1550 nm). In particular, the photoresponsivity and specific detectivity under an 860 nm laser reach 121 A W-1 and 4.3 × 1014 Jones, respectively, whereas the individual nanoflakes show no response under the same wavelength. Meanwhile, the response time at the microsecond (µs) level is obtained, shortened by around 3 orders of magnitude compared to that of the constituting layers. The sensitive and ultrafast photoresponse at the NIR wavelength stems from the strong interlayer transition of sub-band-gap photons and the rapid separation of the photogenerated carriers by the built-in field within the heterojunction area. Our results not only provide an effective approach to achieve sub-band-gap photodetection in 2D perovskite-based structures but also suggest a universal strategy to fabricate high-performance optoelectronic devices.

RALF peptide signaling controls the polytubey block in Arabidopsis.

Fertilization of an egg by multiple sperm (polyspermy) leads to lethal genome imbalance and chromosome segregation defects. In Arabidopsis thaliana, the block to polyspermy is facilitated by a mechanism that prevents polytubey (the arrival of multiple pollen tubes to one ovule). We show here that FERONIA, ANJEA, and HERCULES RECEPTOR KINASE 1 receptor-like kinases located at the septum interact with pollen tube-specific RALF6, 7, 16, 36, and 37 peptide ligands to establish this polytubey block. The same combination of RALF (rapid alkalinization factor) peptides and receptor complexes controls pollen tube reception and rupture inside the targeted ovule. Pollen tube rupture releases the polytubey block at the septum, which allows the emergence of secondary pollen tubes upon fertilization failure. Thus, orchestrated steps in the fertilization process in Arabidopsis are coordinated by the same signaling components to guarantee and optimize reproductive success.

Spatial Variations and Influencing Factors of River Networks in River Basins of China.

Analysis of the spatial variations in river networks and the related influencing factors is crucial for the management and protection of basins. To gain insight into the spatial variations and influencing factors of river networks between large basins, in this study, three river basins from north to south in China (Songhua River Basin, Yellow River Basin and Pearl River Basin) were selected for investigation. First, based on a digital elevation model, different river networks with six drainage accumulation thresholds of three basins were extracted using ArcGIS. The optimal networks were determined through fitting the relationship between the accumulation threshold and related drainage density. Then, we used two indicators, drainage density and water surface ratio, to characterize the spatial variations of three basins. Finally, Pearson's correlation coefficients were calculated between those two indicators and natural/human influencing factors. The results showed that drainage density and water surface ratio decreased from north to south in China and were negatively correlated with natural/human influencing factors. Drainage density was more influenced by natural factors than by human factors, while the opposite was true for water surface ratio. These findings may provide some basis for the management and protection of the river network.

Charge Segregation in the Intrinsically Disordered Region Governs VRN1 and DNA Liquid-like Phase Separation Robustness.

VERNALIZATION1 (VRN1) is a transcriptional repressor involved in plant vernalization that undergoes liquid-liquid phase separation (LLPS) with DNA. The naturally occurring VRN1-like proteins contain two B3 DNA binding domains connected by an intrinsically disordered region (IDR). The IDR length in VRN1-like proteins has a broad distribution, while the charge segregation pattern is largely conserved. We studied the effect of IDR length and charge segregation on DNA-induced VRN1 phase separation. When only neutral residues (Pro-Ser repeats) were used, the phase separation behavior is sensitive to IDR length, changing from gel-like aggregates (L = 40) to liquid-like droplets (L = 100-120) and clear solution (L = 160). When a pair of continuous patches of positive and negative residues were added to the IDRs, all the VRN1 variants formed robust and durable droplets with DNA independent of the IDR length. To test how robust the system is, we introduced folded green fluorescent protein or the enzyme GPX4 into VRN1 variants with charge segregation in IDR, the resulting proteins form LLPS with DNA as well. Our study implies that VRN1-like proteins use conserved charge segregation pattern to retain functional LLPS during evolution, and demonstrates the possibility of using this system to design novel biosensors or bio-factories by introducing various functional modules.

Complicated appendicitis are common during the epidemic period of 2019 novel coronavirus (2019-nCoV).

OBJECTIVES: To assess the prevalence of complicated appendicitis (including gangrene, abscess and perforation) after the outbreak of the 2019-nCoV epidemic and to identify the risk factors associated with complicated appendicitis. METHODS: Two groups were established in the study consisting of: one group for cases of acute appendicitis before the 2019-nCoV epidemic (before January 1, 2020; pre-epidemic group) and another group for those after the epidemic outbreak (after January 1, 2020; epidemic group). These two groups were compared in terms of demographic and clinical characteristics, prevalence of complicated appendicitis, and treatment intention. A multivariate analysis model using binary logistic regression was constructed. RESULTS: A total of 163 patients were included in this study, with 105 in the pre-epidemic group and 58 in the epidemic group. In the epidemic group, the interval from the onset of symptoms to admission was 65.0 h, which is significantly longer than the 17.3 h interval noted in the pre-epidemic group (P < 0.001). The prevalence of complicated appendicitis after the epidemic outbreak was significantly higher than before the outbreak (51.7% vs. 12.4%, P < 0.001). In addition, the epidemic group had a lower score of patient's intention to seek treatment than the pre-epidemic group (9.5 ± 2.7 vs. 3.4 ± 2.6, P < 0.001). Based on the multivariate analysis, the risk factors for complicated appendicitis included the time from symptoms onset to admission (OR = 1.075) and the patients' intention to receive treatment (OR = 0.541). CONCLUSION: Complicated appendicitis was more common in patients with acute appendicitis after the outbreak of the 2019-nCoV epidemic.

[Hydrolysis of COS over MgAl Mixed Oxides Derived from Hydrotalcites].

A series of MgAl hydrotalcite-derived composite oxides were prepared by co-precipitation methods. The effects of calcination temperature, reaction temperature, water vapor volume fraction, and alkali metal addition on the hydrolysis activity of the samples were investigated. The crystal structure, specific surface area, pore structure, and basic position distribution of the composite oxides were characterized using XRD, BET, TPD, and XPS. The results shown that the catalytic activity firstly increased and then decreased with the rise of calcination temperature. Furthermore, the sample that calcined at 650℃ can achieve the best catalytic activity (complete removal of COS lasted for 180 min). Increasing the reaction temperature improved the catalytic activity, which can present excellent catalytic activity and stability at temperatures above 70℃. In addition, the doping of the alkali metal Cs improved the catalytic activity, the complete removal time for COS can be maintained for 480 min.

High Oxygen Treatments Enhance the Contents of Phenolic Compound and Ganoderic Acid, and the Antioxidant and DNA Damage Protective Activities of Ganoderma lingzhi Fruiting Body.

Ganoderma lingzhi is a famous medicinal mushroom used as Chinese medicine or functional food and has been accepted across the globe. It is important to enhance the contents of bioactive compounds, which in turn improves the quality and biological activity of G. lingzhi fruiting body. In this work, freshly harvested G. lingzhi fruiting bodies were treated continuously with air or with 60 and 80% oxygen for 6 days. Samples were collected and determined initially and at 1 day interval during treatment. A high total ganoderic acid content of 29.44 g kg-1 was obtained in samples treated with 60% oxygen at day 3. Quantitative reverse transcriptase (qRT)-PCR and high-performance liquid chromatography (HPLC) analysis showed that the expression levels of hydroxymethylglutaryl-CoA synthase, squalene synthase, and oxidosqualene cyclase genes were substantially increased, resulting in the increase of ganoderic acids A, B, and C2 and ganoderenic acid B. The scavenging activities with 1,1-diphenyl-2-picrylhydrazyl radical, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical, hydroxyl radical, and superoxide radical and the DNA damage protective activity were also enhanced by high oxygen treatment. The results of this work provided a potential method to enhance the active metabolite synthesis in the fruiting body of G. lingzhi.