Transcription factor CsMYB36 regulates fruit neck length via mediating cell expansion in cucumber.

The fruit neck is an important agronomic trait of cucumber (Cucumis sativus). However, the underlying genes and regulatory mechanisms involved in fruit neck development are poorly understood. We previously identified a cucumber yellow-green peel (ygp) mutant, whose causal gene is MYB DOMAIN PROTEIN 36 (CsMYB36). This study showed that the ygp mutant exhibited a shortened fruit neck and repressed cell expansion in the fruit neck. Further functional analysis showed that CsMYB36 was also a target gene, and its expression was enriched in the fruit neck. Overexpression of CsMYB36 in the ygp mutant rescued shortened fruit necks. Furthermore, transcriptome analysis and reverse transcription quantitative PCR (RT-qPCR) assays revealed that CsMYB36 positively regulates the expression of an expansin-like A3 (CsEXLA3) in the fruit neck, which is essential for cell expansion. Yeast 1-hybrid and dual-luciferase assays revealed that CsMYB36 regulates fruit neck elongation by directly binding to the promoter of CsEXLA3. Collectively, these findings demonstrate that CsMYB36 is an important gene in the regulation of fruit neck length in cucumber plants.

The COPII subunit CsSEC23 mediates fruit glossiness in cucumber.

To improve our understanding of the mechanism underlying cucumber glossiness regulation, a novel cucumber mutant with a glossy peel (Csgp) was identified. MutMap, genotyping, and gene editing results demonstrated that CsSEC23, which is the core component of COPII vesicles, mediates the glossiness of cucumber fruit peel. CsSEC23 is functionally conserved and located in the Golgi and endoplasmic reticulum. CsSEC23 could interact with CsSEC31, but this interaction was absent in the Csgp mutant, which decreased the efficiency of COPII vesicle transportation. Genes related to wax and cutin transport were upregulated in the Csgp mutant, and the cuticle structure of the Csgp-mutant peel became thinner. Moreover, the wax and cutin contents were also changed due to CsSEC23 mutation. Taken together, the results obtained from this study revealed that CsSEC23 mediates cucumber glossiness, and this mediating might be affected by COPII vesicle transportation.

Microbulbifer spongiae sp. nov., isolated from marine sponge Diacarnus erythraeanus.

A novel bacterium, designated as MI-GT, was isolated from marine sponge Diacarnus erythraeanus. Cells of strain MI-GT are Gram-stain-negative, aerobic, and rod or coccoid-ovoid in shape. MI-GT is able to grow at 10-40 °C (optimum, 28 °C), with 1.0-8.0% (w/v) NaCl (optimum, 4.0%), and at pH 5.5-9.0 (optimum, pH 8.0). The 16S rRNA gene sequence of strain MI-GT shows 98.35, 97.32 and 97.25% similarity to those of Microbulbifer variabilis Ni-2088T, Microbulbifer maritimus TF-17T and Microbulbifer echini AM134T, respectively. Phylogenetic analysis also exhibits that strain MI-GT falls within a clade comprising members of the genus Microbulbifer (class Gammaproteobacteria). The genome size of strain MI-GT is 4478124 bp with a G+C content of 54.51 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain MI-GT and other type strains are 71.61-76.44% (ANIb), 83.27-84.36% (ANIm) and 13.4-18.7% (dDDH), respectively. These values are significantly lower than the recommended threshold values for bacterial species delineation. Percentage of conserved proteins and average amino acid identity values among the genomes of strain MI-GT and other closely related species are 52.04-59.13% and 67.47-77.21%, respectively. The major cellular fatty acids of MI-GT are composed of summed feature 8 (C18 : 1 ω7c or C18 : 1 ω6c), iso-C11 : 0 3-OH, iso-C15 : 0, C16 : 0, and summed feature 9 (C17 : 1 iso ω9c or C16 : 0 10-methyl). The polar lipids of MI-GT mainly consist of phosphatidylethanolamine, phosphatidylglycerol, aminolipid, and two glycolipids. The major respiratory quinone is Q-8. Based on differential phenotypic and phylogenetic data, strain MI-GT is considered to represent a novel species of genus Microbulbifer, for which the name Microbulbifer spongiae sp. nov. is proposed. The type strain is MI-GT (=MCCC 1K07826T=KCTC 8081T).

Cytobacillus spongiae sp. nov. isolated from sponge Diacarnus spinipoculum.

A novel Gram-stain-positive, aerobic and motile bacterium, designated strain CY-GT, was isolated from a sponge (Diacarnus spinipoculum) collected from the Red Sea. The strain grew at 13-43 °C (optimum 30 °C), pH 5.5-10.0 (optimum pH 9.0) and with 0-8.0 % (w/v) (0-1.37 M) NaCl (optimum 0 %). The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that CY-GT represents a member of the genus Cytobacillus, with the highest sequence identity to Cytobacillus oceanisediminis H2T (97.05 %), followed by Cytobacillus firmus IAM 12464T (96.76 %). The major cellular fatty acids (>5 % of the total) of CY-GT were C15 : 0iso, C16 : 0iso, C16 : 1ω7c alcohol, C16 : 0, C17 : 1iso ω10c and C17 : 0iso. The major polar lipids were glycolipid, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The major respiratory quinone is menaquinone-7 (MK-7). The cell-wall peptidoglycan contains meso-diaminopimelic acid. The total genome size of CY-GT is 4 789 051 bp. The DNA G+C content is 38.83 mol%. The average nucleotide identity and DNA-DNA hybridization among CY-GT and type strains of other species of the genus Cytobacillus were 76.79-78.97 % and 20.10-24.90 %, respectively. On the basis of the results of phylogenetic analysis, physiological and biochemical characterization, strain CY-GT represents a novel species of the genus Cytobacillus, for which the name Cytobacillus spongiae sp. nov. is proposed. The type strain is CY-GT (=MCCC 1K06383T=KCTC 43348T).

Bioinspired Polysaccharide Derivative with Efficient and Stable Lubrication for Silicon-Based Devices.

It is becoming increasingly important to synthesize efficient biomacromolecule lubricants suitable for medical devices. Even though the development of biomimetic lubricants has made great progress, the current system suitable for hydrophobic silicone-based medical devices is highly limited. In this work, we synthesize one kind of novel polysaccharide-derived macromolecule lubricant of chitosan (CS) grafted polyethylene glycol (PEG) chains and catechol groups (CT) (CS-g-PEG-g-CT). CS-g-PEG-g-CT shows good adsorption ability by applying quantitative analysis of quartz crystal microbalance (QCM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and confocal fluorescence imaging technique, as well as the typical shear-thinning feature. CS-g-PEG-g-CT exhibits low and stable coefficients of friction (COFs) (0.01-0.02) on polydimethylsiloxane (PDMS) surfaces at a wide range of mass concentrations in diverse media including pure water, physiological saline, and PBS buffer solution and is even tolerant to various normal loads and sliding frequencies for complex pressurizing or shearing environments. Subsequently, systematic surface characterizations are used to verify the dynamic attachment ability of the CS-g-PEG-g-CT lubricant on the loading/shearing process. The lubrication mechanism of CS-g-PEG-g-CT can be attributed to the synergy of strong adsorption from catechol groups to form a uniform assembly layer, excellent hydration effect from PEG chains, and typical shear-thinning feature to dissipate viscous resistance. Surprisingly, CS-g-PEG-g-CT exhibits efficient lubricity on silicone-based commercial contact lenses and catheters. The current macromolecule lubricant demonstrates great real application potential in the fields of medical devices and disease treatments.

Precision diagnosis and therapy of a case of brain abscesses associated with asymptomatic pulmonary arteriovenous fistulas.

BACKGROUND: Brain abscesses, a severe infectious disease of the CNS, are usually caused by a variety of different pathogens, which include Streptococcus intermedius (S. intermedius). Pulmonary arteriovenous fistulas (PAVFs), characterized by abnormal direct communication between pulmonary artery and vein, are a rare underlying cause of brain abscesses. CASE PRESENTATION: The patient was a previous healthy 55-year-old man who presented with 5 days of headache and fever. Cerebral magnetic resonance imaging (MRI) suggested a brain abscess. Thoracic CT scan and angiography demonstrated PAVFs. Aiding by metagenomic next-generation sequencing (mNGS) of the cerebrospinal fluid (CSF) sample which identified S. intermedius as the causative pathogen, the patient was switched to the single therapy of large dose of penicillin G and was cured precisely and economically. CONCLUSIONS: It is an alternative way to perform mNGS to identify causative pathogens in patients with brain abscesses especially when the results of traditional bacterial culture were negative. Further thoracic CT or pulmonary angiography should also be undertaken to rule out PAVFs as the potential cause of brain abscess if the patient without any known premorbid history.

Unique high-temperature tolerance mechanisms of zoochlorellae Symbiochlorum hainanensis derived from scleractinian coral Porites lutea.

Global warming is a key issue that causes coral bleaching mainly because of the thermosensitivity of zooxanthellae. Compared with the well-studied zooxanthellae Symbiodiniaceae in coral holobionts, we rarely know about other coral symbiotic algae, let alone their thermal tolerance. In this study, a zoochlorellae, Symbiochlorum hainanensis, isolated from the coral Porites lutea, was proven to have a threshold temperature of 38°C. Meanwhile, unique high-temperature tolerance mechanisms were suggested by integrated transcriptomics and real-time quantitative PCR, physiological and biochemical analyses, and electron microscopy observation. Under heat stress, S. hainanensis shared some similar response strategies with zooxanthellae Effrenium sp., such as increased ascorbate peroxidase, glutathione peroxidase, superoxide dismutase activities and chlorophyll a, thiamine, and thiamine phosphate contents. In particular, more chloroplast internal layered structure, increased CAT activity, enhanced selenate reduction, and thylakoid assembly pathways were highlighted for S. hainanensis's high-temperature tolerance. Notably, it is the first time to reveal a whole selenate reduction pathway from SeO42- to Se2- and its contribution to the high-temperature tolerance of S. hainanensis. These unique mechanisms, including antioxidation and maintaining photosynthesis homeostasis, efficiently ensure the high-temperature tolerance of S. hainanensis than Effrenium sp. Compared with the thermosensitivity of coral symbiotic zooxanthellae Symbiodiniaceae, this study provides novel insights into the high-temperature tolerance mechanisms of coral symbiotic zoochlorellae S. hainanensis, which will contribute to corals' survival in the warming oceans caused by global climate change. IMPORTANCE: The increasing ocean temperature above 31°C-32°C might trigger a breakdown of the coral-Symbiodiniaceae symbioses or coral bleaching because of the thermosensitivity of Symbiodiniaceae; therefore, the exploration of alternative coral symbiotic algae with high-temperature tolerance is important for the corals' protection under warming oceans. This study proves that zoochlorellae Symbiochlorum hainanensis can tolerate 38°C, which is the highest temperature tolerance known for coral symbiotic algae to date, with unique high-temperature tolerance mechanisms. Particularly, for the first time, an internal selenium antioxidant mechanism of coral symbiotic S. hainanensis to high temperature was suggested.

A Novel and Green Method for Preparing Highly Conductive PEDOT:PSS Films for Thermoelectric Energy Harvesting.

As a π-conjugated conductive polymer, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is recognized as a promising environmentally friendly thermoelectric material. However, its low conductivity has limited applications in the thermoelectric field. Although thermoelectric efficiency can be significantly enhanced through post-treatment doping, these processes often involve environmentally harmful organic solvents or reagents. In this study, a novel and environmentally benign method using purified water (including room temperature water and subsequent warm water) to treat PEDOT:PSS film has been developed, resulting in improved thermoelectric performance. The morphology data, chemical composition, molecular structure, and thermoelectric performance of the films before and after treatment were characterized and analyzed using a scanning electron microscope (SEM), Raman spectrum, XRD pattern, X-ray photoelectron spectroscopy (XPS), and a thin film thermoelectric measurement system. The results demonstrate that the water treatment effectively removes nonconductive PSS from PEDOT:PSS composites, significantly enhancing their conductivity. Treated films exhibit improved thermoelectric properties, particularly those treated only 15 times with room temperature water, achieving a high electrical conductivity of 62.91 S/cm, a Seebeck coefficient of 14.53 µV K-1, and an optimal power factor of 1.3282 µW·m-1·K-2. In addition, the subsequent warm water treatment can further enhance the thermoelectric properties of the film sample. The underlying mechanism of these improvements is also discussed.

Revisiting the Green Growth Effect of Foreign Direct Investment from the Perspective of Environmental Regulation: Evidence from China.

The inflow of foreign direct investment (FDI) has both advanced China's economic development process and influenced the ecological quality of China's regions. Under the deepening of economic globalization and the continuous deterioration in environmental quality, the correlation mechanism between foreign direct investment, environmental regulation, and economic growth is becoming increasingly complex. Therefore, based on the slacks-based measure (SBM) model and the Global Malmquist-Luenberger (GML) index, this study measured the level of green economic growth using data from 30 provinces and cities from 2004-2019 and constructed a panel fixed-effect regression model to study the effect of foreign direct investment on green economic growth in China. The study found that foreign direct investment significantly promoted green economic growth in China, foreign direct investment promoted green economic growth through independent innovation and inhibited green economic growth through imitation innovation, and environmental regulation moderated the impact of foreign direct investment on green economic growth. This paper incorporated foreign direct investment, heterogeneous technological innovation, green economic growth, and environmental regulation into the research framework, and thereby further enriched and improved the research on the theoretical mechanism of green economic growth. The research conclusion clarified the influence mechanism of foreign capital on the quality of China's economic development, which was conducive to the formulation of more reasonable policies for attracting investments and to the promotion of the formation of a positive interaction mechanism between environmental regulation and foreign direct investment, which is of great practical significance for China's economy to achieve sustainable development.

Fabrication of Highly Conductive Porous Fe3O4@RGO/PEDOT:PSS Composite Films via Acid Post-Treatment and Their Applications as Electrochemical Supercapacitor and Thermoelectric Material.

As a remarkable multifunctional material, ferroferric oxide (Fe3O4) exhibits considerable potential for applications in many fields, such as energy storage and conversion technologies. However, the poor electronic and ionic conductivities of classical Fe3O4 restricts its application. To address this challenge, Fe3O4 nanoparticles are combined with graphene oxide (GO) via a typical hydrothermal method, followed by a conductive wrapping using poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic sulfonate) (PEDOT:PSS) for the fabrication of composite films. Upon acid treatment, a highly conductive porous Fe3O4@RGO/PEDOT:PSS hybrid is successfully constructed, and each component exerts its action that effectively facilitates the electron transfer and subsequent performance improvement. Specifically, the Fe3O4@RGO/PEDOT:PSS porous film achieves a high specific capacitance of 244.7 F g-1 at a current of 1 A g-1. Furthermore, due to the facial fabrication of the highly conductive networks, the free-standing film exhibits potential advantages in flexible thermoelectric (TE) materials. Notably, such a hybrid film shows a high electric conductivity (σ) of 507.56 S cm-1, a three times greater value than the Fe3O4@RGO component, and achieves an optimized Seebeck coefficient (S) of 13.29 µV K-1 at room temperature. This work provides a novel route for the synthesis of Fe3O4@RGO/PEDOT:PSS multifunctional films that possess promising applications in energy storage and conversion.

The Use of Various Measurement Methods for Estimating the Fracture Energy of PLA (Polylactic Acid).

The essential work of fracture (EWF) and Izod/Charpy impact tests have been used to investigate the fracture toughness in the plane stress of brittle polymers. In this paper, we had three goals: first, we aimed to employ how to estimate PLA toughness in different geometries; then, we proposed to compare Izod and Charpy Impact toughness in the same geometry; finally, we intended to determine the difference between EWF toughness and dynamic toughness. The results showed that the EWF method could be applied to evaluate PLA fracture behavior with small ligaments (2-4 mm), while the dynamic test could be employed with larger ligaments (5-7 mm). A comparison of the two impact test results obtained the following conclusions: Charpy impact toughness was higher than Izod impact toughness in the same geometry, and the impact toughness under a notch angle of 90° was larger than that of an angle of 45°. Both EWF and dynamic tests can be used to explore PLA toughness with small ligaments. The fracture energy decreases with ligament size in the EWF test, but it increases in the dynamic test.

Advances in Understanding and Harnessing the Molecular Regulatory Mechanisms of Vegetable Quality.

The quality of vegetables is facing new demands in terms of diversity and nutritional health. Given the improvements in living standards and the quality of consumed products, consumers are looking for vegetable products that maintain their nutrition, taste, and visual qualities. These requirements are directing scientists to focus on vegetable quality in breeding research. Thus, in recent years, research on vegetable quality has been widely carried out, and many applications have been developed via gene manipulation. In general, vegetable quality traits can be divided into three parts. First, commodity quality, which is most related to the commerciality of plants, refers to the appearance of the product. The second is flavor quality, which usually represents the texture and flavor of vegetables. Third, nutritional quality mainly refers to the contents of nutrients and health ingredients such as soluble solids (sugar), vitamin C, and minerals needed by humans. With biotechnological development, researchers can use gene manipulation technologies, such as molecular markers, transgenes and gene editing to improve the quality of vegetables. This review attempts to summarize recent studies on major vegetable crops species, with Brassicaceae, Solanaceae, and Cucurbitaceae as examples, to analyze the present situation of vegetable quality with the development of modern agriculture.

Molecular Engineering Super-Robust Dry/Wet Adhesive with Strong Interface Bonding and Excellent Mechanical Tolerance.

Despite the fact that synthetic adhesives have achieved great progress, achieving robust dry/wet adhesion under harsh operating environments is still challenging. Herein, inspired from the extraordinary adhesion mechanism of nature mussel protein adhesive, the balanced design concept of co-adhesion and interfacial adhesion is proposed to prepare one kind of novel copolymer adhesive of [poly(dopamine methacrylamide-co-methoxethyl acrylate-co-adamantane-1-carboxylic acid 2-(2-methyl-acryloyloxy)-ethyl ester)] [p(DMA-co-MEA-co-AD)], named as super-robust adhesive (SRAD). The SRAD exhibits ultra-high interface bonding strengths in air (∼7.66 MPa) and underwater (∼2.78 MPa) against an iron substrate. Especially, a greatly tough and stable adhesion strength (∼2.11 MPa) can be achieved after immersing the bonded sample in water for half a year. Furthermore, the SRAD demonstrates surprising wet bonding robustness/tolerance even encountering harsh conditions such as fluid shearing, dynamic loading, and cyclic mechanical fretting. The great advantages of SRAD, such as strong interface bonding, stable wet adhesion underwater, and good mechanical tolerance, makes it demonstrate huge application potential in engineering sealants and underwater adhesion.

Fabrication of acid-resistant imprinted layer on magnetic nanomaterials for selective extraction of chlorogenic acid in Honeysuckle.

The common elution process of molecularly imprinted polymers (MIPs) is carried out in an acidic medium, which greatly affects the stability and reusability of synthetic MIPs, especially for magnetic MIPs. In this study, we fabricated an acid-resistant imprinted layer formed by phase-transitioned lysozyme on magnetic nanomaterials for selective extraction of chlorogenic acid in Honeysuckle, which often coexists with structural analogs. The newly designed acid-resistant imprinted layer can not only protect the internal magnetic core from denudation and dissolution, but also maintain the integrity of the imprinted layer during the elution process. The resultant magnetic MIPs exhibited good stability with no change on morphology after the repeatedly eluting process, and satisfactory reusability that can be used at least ten adsorption-desorption cycles with almost no decrease for adsorption capacity. In addition, the resultant materials possess satisfactory magnetism, uniform morphology with typical core-shell structure, stable crystallization, and good adsorption performance showing on high adsorption amount (10.82 mg g-1), fast kinetic equilibrium time (as short as 30 min), and satisfactory selectivity (IF = 2.85, SC > 1.5). At last, the obtained magnetic MIPs as adsorbents coupled with HPLC were successfully used to selective extract CGA in Honeysuckle samples with the high recoveries in the range of 92.0-104.4%, and the contents of CGA in Honeysuckle samples from the different origin are calculated in the range of 0.98%-1.24%.

Development and Validation of a Simple-to-Use Nomogram for Predicting In-Hospital Mortality in Patients With Acute Heart Failure Undergoing Continuous Renal Replacement Therapy.

Background: Patients with acute heart failure (AHF) who require continuous renal replacement therapy (CRRT) have a high risk of in-hospital mortality. It is clinically important to screen high-risk patients using a model or scoring system. This study aimed to develop and validate a simple-to-use nomogram consisting of independent prognostic variables for the prediction of in-hospital mortality in patients with AHF undergoing CRRT. Methods: We collected clinical data for 121 patients with a diagnosis of AHF who underwent CRRT in an AHF unit between September 2011 and August 2020 and from 105 patients in the medical information mart for intensive care III (MIMIC-III) database. The nomogram model was created using a visual processing logistic regression model and verified using the standard method. Results: Patient age, days after admission, lactic acid level, blood glucose concentration, and diastolic blood pressure were the significant prognostic factors in the logistic regression analyses and were included in our model (named D-GLAD) as predictors. The resulting model containing the above-mentioned five factors had good discrimination ability in both the training group (C-index, 0.829) and the validation group (C-index, 0.740). The calibration and clinical effectiveness showed the nomogram to be accurate for the prediction of in-hospital mortality in both the training and validation cohort when compared with other models. The in-hospital mortality rates in the low-risk, moderate-risk, and high-risk groups were 14.46, 40.74, and 71.91%, respectively. Conclusion: The nomogram allowed the optimal prediction of in-hospital mortality in adults with AHF undergoing CRRT. Using this simple-to-use model, the in-hospital mortality risk can be determined for an individual patient and could be useful for the early identification of high-risk patients. An online version of the D-GLAD model can be accessed at https://ahfcrrt-d-glad.shinyapps.io/DynNomapp/. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT0751838.

A coumarin-containing Schiff base fluorescent probe with AIE effect for the copper(ii) ion.

A novel coumarin-derived Cu2+-selective Schiff base fluorescent "turn-off" chemosensor CTPE was successfully obtained, which showed an AIE effect. It could identify Cu2+ by quenching its fluorescence. The lower limit of detection was 0.36 µM. CTPE can act as a highly selective and sensitive fluorescence probe for detecting Cu2+.

Study on Adenovirus Infection in vitro with Nanoself-Assembling Peptide as Scaffolds for 3D Culture.

PURPOSE: To construct a three-dimensional (3D) culture model of adenovirus in vitro using the nanoself-assembling peptide RADA16-I as a 3D cell culture scaffold combined with virology experimental technology to provide a novel research method for virus isolation and culture, pathogenesis research, antiviral drug screening and vaccine preparation. METHODS: The nanoself-assembling peptide RADA16-I was used as a 3D scaffold material for 293T cell culture, and adenovirus was cultured in the cells. The growth, morphological characteristics and pathological effects of 3D-cultured 293T cells after adenovirus infection were observed with an inverted microscope and MTS. The proliferation of adenovirus in 293T cells was observed by TEM and detected by qPCR. The levels of TNF-α and IL-8 secreted by adenovirus-infected 293T cells in the RADA16-I 3D culture system were detected by ELISA. RESULTS: The 293T cells grew well in the RADA16-I 3D culture system for a prolonged period of time. The adenovirus infection persisted for a long time with multiple proliferation peaks, which closely resembled those of in vivo infections. The adenovirus virions amplified in the 3D system remained infectious. There were multiple secretion peaks of TNF-α and IL-8 secretion levels in adenovirus-infected 293T cells cultured in 3D culture systems. CONCLUSION: The nanoself-assembling peptide RADA16-I can be used as a 3D scaffold for adenovirus isolation, culture and research. The 3D culture system shows more realistic in vivo effects than two-dimensional (2D) culture.

Aldehyde Dehydrogenase 2 Protects Against Post-Cardiac Arrest Myocardial Dysfunction Through a Novel Mechanism of Suppressing Mitochondrial Reactive Oxygen Species Production.

Post-cardiac arrest myocardial dysfunction significantly contributes to early mortality after the return of spontaneous circulation. However, no effective therapy is available now. Aldehyde dehydrogenase 2 (ALDH2) enzyme has been shown to protect the heart from aldehyde toxicity such as 4-hydroxy-2-nonenal (4-HNE) and oxidative stress. In this study, we evaluated the effect of enhanced activity or expression of ALDH2 on post-cardiac arrest myocardial dysfunction and survival in a rat cardiac arrest model. Furthermore, we elucidated the underlying mechanisms with a focus on mitochondrial reactive oxygen species (ROS) production in a cell hypoxia/reoxygenation model. A total of 126 rats were used for the ALDH2 activation or cardiac overexpression of ALDH2 studies. Randomization was done 10 min before the respective agonist injection or in vivo gene delivery. We showed that enhanced activity or expression of ALDH2 significantly improved contractile function of the left ventricle and survival rate in rats subjected to cardiac arrest-cardiopulmonary resuscitation procedure. Moreover, ALDH2 prevented cardiac arrest-induced cardiomyocyte death from apoptosis and mitochondrial damage. Mechanistically, 4-HNE, a representative substrate of ALDH2, was dominantly increased in the hypoxia/reoxygenation-exposed cardiomyocytes. Direct addition of 4-HNE led to significantly augmented succinate accumulation and mitochondrial ROS production. Through metabolizing 4-HNE, ALDH2 significantly inhibited mitochondrial ROS production. Our findings provide compelling evidence of the cardioprotective effects of ALDH2 and therapeutic targeting this enzyme would provide an important approach for treating post-cardiac arrest myocardial dysfunction.

Synthesizing Functional Biomacromolecular Wet Adhesives with Typical Gel-Sol Transition and Shear-Thinning Features.

Functional wet adhesives have become increasingly important in the field of biomedicine. Herein, modified chitosan (CS) biomacromolecule is synthesized as tissue wet adhesives and hemostatic materials. In a typical case, after getting through two steps of organic reactions, catechol and lysine groups are grafted onto the chitosan backbone, enabling for the successful preparation of one kind of novel biomacromolecule of chitosan-catechol-lysine (CHIC-Lys). The as-prepared CHIC-Lys biomacromolecule shows improved wet adhesion strength, concentration-dependent gel-sol transition feature when shear stress is cycled between low stress (0.2 Pa) and high stress (2 Pa) at room temperature, and obvious shear-thinning feature under wide concentration ranges, along with good biocompatibility, comparable with traditional CS. Based on these obvious characteristics, CHIC-Lys is successfully coated onto the surface of a syringe needle and the decorated needle shows considerable hemostatic effect in a test of rats venous bleeding. Overall, the as-synthesized CHIC-Lys biomacromolecule exhibits considerable application potential in the biomedical field.

Highly-efficient amphiphilic magnetic nanocomposites based on a simple sol-gel modification for adsorption of phthalate esters.

In this work, a novel amphiphilic magnetic nanocomposite (Fe3O4@A-O) used for the adsorption of phthalate esters was synthesized by a simple sol-gel surface modification method, during which hydrophilic amino groups of 3-aminopropyltriethoxylsilane and hydrophobic alkyl chains of N-octyltrimethoxysilane were modified onto Fe3O4 nanoparticles. Morphologies and surface structures of as-prepared magnetic nanomaterials were characterized in detail. The preparation, adsorption, and desorption conditions of Fe3O4@A-O were investigated systematically and the adsorption mechanism was discussed. The Fe3O4@A-O exhibits quite fast adsorption for six phthalate esters, which only takes two minutes and is 10 ∼ 720 times shorter than other reported adsorbents. Theoretical adsorption capacities of Fe3O4@A-O for dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, and didecyl phthalate are >1000 mg/g according to the Freundlich fitting. With ethanol as desorption solvent, it only takes one minute to reach desorption equilibrium. In addition, Fe3O4@A-O can be collected from aqueous solution with an applied magnet in just three seconds, and it shows satisfactory stability and reusability after recycling 10 times. The developed amphiphilic adsorbent exhibits great promises in the removal of phthalate esters because of its easy preparation, excellent adsorption and desorption performances, rapid magnetic separation, and good reusability.