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Crystalline/crystalline blends of polymer have shown advantages in the preparation of new polymeric materials. However, the regulation of co-crystallization in a blend is still full of challenges due to the preferential self-crystallization driven by thermodynamics. Here, an inclusion complex approach is proposed to facilitate the co-crystallization between crystalline polymers, because the crystallization process displays a prominent kinetics advantage when polymer chains are released from the inclusion complex. Poly(butylene succinate) (PBS), poly(butylene adipate) (PBA) and urea are chosen to form co-inclusion complexes, where PBS and PBA chains play as isolated guest molecules and urea molecules construct the host channel framework. The coalesced PBS/PBA blends are obtained by fast removing the urea framework and systematically investigated by differential scanning calorimetry, X-ray diffraction, proton nuclear magnetic resonance and Fourier transformation infrared spectrometry. It is demonstrated that PBA chains are co-crystallized into PBS extended-chain crystals in the coalesced blends, while such a phenomenon has not been detected in simply co-solution-blended samples. Though PBA chains could not be totally accommodated in the PBS extended-chain crystals, their co-crystallized content increases with the initial feeding ratio of PBA. Consequently, the melting point of the PBS extended-chain crystal gradually declines from 134.3 °C to 124.2 °C with an increasing PBA content. The PBA chains playing as defects mainly induce lattice expansion along the a-axis. In addition, when the co-crystals are soaked in tetrahydrofuran, some of the PBA chains are extracted out, leading to damage to the correlative PBS extended-chain crystals. This study shows that co-inclusion complexation with small molecules could be an effective way to promote co-crystallization behavior in polymer blends.
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Co-crystallization plays a crucial role in the integration and regulation of thermal and mechanical properties in polymer blends, but the poor compatibility of the components in the crystal phase has always been a major obstacle to co-crystallization, which puts forward stricter requests for linkage and interaction between different entities. On the basis of the hydrogen-bonding interaction that can promote chain stacking and thus improve miscibility, we propose that crystalline/crystalline blends of 2-ureido-4[1H]-pyrimidinone (UPy)-functionalized poly(butylene succinate) and poly(butylene fumarate) (PBS-UPy/PBF-UPy) where UPy groups with quadruple hydrogen-bonding interaction are employed to connect different chain ends, could inhibit phase separation and improve co-crystallization. PBS-UPy/PBF-UPy blends exhibit complex component-dependent and cooling-rate-dependent co-crystallization behavior. A high level of co-crystallization occurs in the range of PBS-UPy-rich fractions, and the proportion could approach over 98% under optimized conditions with the aid of UPy quadruple hydrogen bonds interaction. This work enriches the understanding of co-crystallization in crystalline/crystalline polymer blends and provides more possibility for the design of structures and properties of polymer materials.
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Fumaratos , Polímeros , Cristalización , Polímeros/química , Pirimidinonas , HidrógenoRESUMEN
Protein prenylation is an essential posttranslational modification and includes protein farnesylation and geranylgeranylation using farnesyl diphosphate or geranylgeranyl diphosphate as substrates, respectively. Geranylgeranyl diphosphate synthase is a branch point enzyme in the mevalonate pathway that affects the ratio of farnesyl diphosphate to geranylgeranyl diphosphate. Abnormal geranylgeranyl diphosphate synthase expression and activity can therefore disrupt the balance of farnesylation and geranylgeranylation and alter the ratio between farnesylated and geranylgeranylated proteins. This change is associated with the progression of nonalcoholic fatty liver disease (NAFLD), a condition characterized by hepatic fat overload. Of note, differential accumulation of farnesylated and geranylgeranylated proteins has been associated with differential stages of NAFLD and NAFLD-associated liver fibrosis. In this review, we summarize key aspects of protein prenylation as well as advances that have uncovered the regulation of associated metabolic patterns and signaling pathways, such as Ras GTPase signaling, involved in NAFLD progression. Additionally, we discuss unique opportunities for targeting prenylation in NAFLD/hepatocellular carcinoma with agents such as statins and bisphosphonates to improve clinical outcomes.
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Farnesiltransferasa/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Fosfatos de Poliisoprenilo/metabolismo , Prenilación de Proteína , Procesamiento Proteico-Postraduccional , Animales , Progresión de la Enfermedad , Humanos , Enfermedad del Hígado Graso no Alcohólico/metabolismoRESUMEN
A salt-tolerant microbe strain JYZ-SD2 was investigated to develop biological soil amendments to stimulate salix growth and acclimation in costal salt-affected soils. The salt tolerance mechanism of strain JYZ-SD2 was investigated by detecting the salt-tolerant growth characteristics, biofilm formation, ion distribution, secondary metabolites, and zymogram profiling. The strain was identified by physiological and biochemical characteristics (Biolog), 16S rDNA sequencing, and cry1/7/9 gene expressing. With increasing of NaCl concentration, strain JYZ-SD2 adapted to the increased osmotic pressure by prolonging the retardation period, slowing down the growth rate of the logarithmic phase, increasing spo0A gene expression, increasing biofilm formation, reducing Na+ uptake, and changing the expression of metabolites and intracellular soluble proteins. The results showed that strain JYZ-SD2 could be assigned to Bacillus cereus.
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Bacillus cereus/clasificación , Rizosfera , Salix/microbiología , Tolerancia a la Sal , Plantas Tolerantes a la Sal/microbiología , Bacillus cereus/aislamiento & purificación , Biopelículas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Cloruro de Sodio , Microbiología del Suelo , Estrés FisiológicoRESUMEN
A greenhouse experiment was conducted to assess the adverse impact of transgenic cotton on ecosystem and environment via effect of transgenic Bt+CpTI cotton root exudates on growth and antioxidant activity of conventional parental cotton. Results showed elevated reductive and oxidative species activities in the leaves of conventional parental cotton seedlings treated with varying concentrations of transgenic cotton root exudates. Compared to control, 14.9% to 39.9% increase in catalase, 8.8% to 114% increase in for peroxidase, 21.3% to 59.7% increase in phenylalanine ammonia-lyase and 5.8 to 19.5 fold in ascorbate specific peroxidase was observed. However, biomass and height of conventional cotton seedlings were not affected by any concentration of transgenic cotton root exudates. These results suggested that cultivation of transgenic Bt+CpTI cotton plants poses little risk to conventional parental cotton based on their root interactions.
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Antioxidantes/metabolismo , Gossypium/genética , Gossypium/metabolismo , Exudados de Plantas/farmacología , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Biomasa , Ecosistema , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas , Gossypium/crecimiento & desarrollo , Exudados de Plantas/química , Exudados de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrolloRESUMEN
This study developed a prototype for a rotational cone-beam x-ray luminescence computed tomography (CB-XLCT) system, considering its potential application in pre-clinical theranostic imaging. A geometric calibration method applicable to both imaging chains (XL and CT) was also developed to enhance image quality. The results of systematic performance evaluations were presented to assess the feasibility of commercializing XLCT technology. Monte Carlo GATE simulation was performed to determine the optimal imaging conditions for nanophosphor particles (NPs) irradiated by 70 kV x-rays. We acquired a low-dose transmission x-ray tube and designed a prone positioning platform and a rotating gantry, using mice as targets from commercial small animalµ-CT systems. We then employed the image cross-correlation (ICC) automatic geometric calibration method to calibrate XL and CT images. The performance of the system was evaluated through a series of phantom experiments with a linearity of 0.99, and the contrast-to-noise ratio (CNR) between hydroxyl-apatite (HA) and based epoxy resin is 19.5. The XL images of the CB-XLCT prototype achieved a Dice similarity coefficient (DICE) of 0.149 for a distance of 1 mm between the two light sources. Finally, the final XLCT imaging results were demonstrated using the Letter phantoms with NPs. In summary, the CB-XLCT prototype developed in this study showed the potential to achieve high-quality imaging with acceptable radiation doses for small animals. The performance of CT images was comparable to current commercial machines, while the XL images exhibited promising results in phantom imaging, but further efforts are needed for biomedical applications.
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Procesamiento de Imagen Asistido por Computador , Luminiscencia , Animales , Ratones , Rayos X , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada de Haz Cónico/métodos , Fantasmas de ImagenRESUMEN
Utilization of rhizosphere microorganisms to improve plant growth and salt tolerance has recently attracted widespread attention. The growth and salt tolerance of willows inoculated with Bacillus cereus JYZ-SD2 and Peniophora cinerea XC were studied under different salt stress conditions. The results showed that the chlorophyll content of willow cuttings inoculated with the XC strain increased significantly by 51.27%. After salt stress of willow cuttings inoculated with B. cereus JYZ-SD2 and P. cinerea XC (solely or in combination), the amount of sodium in the roots from the epidermis to the pericycle decreased and the content of sodium in the pericycle was significantly lower than that of the uninoculated willow, while the proportion of potassium increased. Willow cuttings inoculated with microorganisms showed increased activity of SOD and POD. At the salt concentration of 100 mmol/L, the highest SOD activity was found in B. cereus JYZ-SD2-inoculated willows, with 59.88% increase compared to uninoculated willows; the highest POD activity was found in P. cinerea XC and B. cereus JYZ-SD2 co-inoculated willows, with 51.05% increase compared to uninoculated willows. The Na-K-ATPase and Ca-Mg-ATPase activities of inoculated P. cinerea XC willow cuttings were also 59.38% and 60% higher than that of uninoculated willows, respectively. The qPCR analysis showed that the expression of vp2 gene in the microorganism-inoculated willow leaves was always higher than that in willow alone. The expression of vp2 gene in P. cinerea XC-inoculated willow cuttings was 270.81% higher than that in uninoculated willows. Further observation of the ultrastructure of root cells under salt stress revealed that most of the vesicles in the root tip cells of willow were intact and secreted phagocytic vesicles to absorb sodium ions in the cytoplasm. This study shows that the combined beneficial fungi and rhizosphere-promoting bacteria inoculation technology as a practical biotechnological approach to enhance the growth of willows in salt-affected soils.
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Bacillus cereus , Rizosfera , Salix , Tolerancia a la Sal , Adenosina Trifosfatasas/metabolismo , Bacillus cereus/metabolismo , Raíces de Plantas/microbiología , Salix/microbiología , Salix/fisiología , Superóxido Dismutasa/metabolismoRESUMEN
Objective: To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate acupuncture's clinical effect on insulin resistance (IR) in women with polycystic ovary syndrome (PCOS). Methods: PubMed, Cochrane Library, Embase databases, and Chinese databases, including China National Knowledge Infrastructure, Technology Journal Database, and Wanfang Database, were searched without language restrictions from inception to December 20, 2021. Only RCTs in which acupuncture had been examined as the sole or adjunctive PCOS-IR treatment were included. Our primary endpoint was the homeostasis model assessment of insulin resistance (HOMA-IR). The secondary outcomes were fasting blood glucose (FBG), fasting insulin (FINS), body mass index (BMI), and adverse events. Results: Our analysis included 17 eligible RCTs (N = 1511 participants). Compared with other treatments, acupuncture therapy yielded a greater mean reduction in HOMA-IR (MD = -0.15; 95% CI, -0.27 to -0.03; P = 0.01) and BMI (MD = -1.47; 95% CI, -2.46 to -0.47; P = 0.004). Besides acupuncture was associated with a lower risk of adverse events than other treatments (RR, 0.15; 95% CI, 0.10 to 0.22; P < 0.01). Additionally, the combination treatment of acupuncture and medicine is more effective in improving HOMA-IR (MD = -0.91; 95% CI, -1.11 to -0.71; P < 0.01), FBG (MD = -0.30; 95% CI, -0.56 to -0.04; P = 0.02), FINS (MD = -2.33; 95% CI, -2.60 to -2.06; P < 0.01) and BMI (MD = -1.63; 95% CI, -1.94 to -1.33; P < 0.01) than medicine alone. Conclusions: Acupuncture is relatively effective in improving HOMA-IR and BMI in PCOS-IR. Besides, it's safer than other treatments and could be an adjuvant strategy for improving PCOS-IR. Further large-scale, long-term RCTs with strict methodological standards are justified.
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To preliminarily explore the antibiotic concentration distribution characteristics of Guizhou Chishui River basin surface water and potential ecological risks, we used solid phase extraction liquid chromatography tandem mass spectrometry (SPE-HPLC- MS) to analyze 21 types of antibiotics in surface water samples. Twelve types of antibiotics were detected in the Chishui River basin surface water, and the total concentrations of ofloxacin, sulfadiazine, and trimethoprim ranged from ND-1166.97 ng·L-1, with a detection rate of 100%. On average, the highest concentration of the three types of antibiotics detected were ofloxacin (221.59 ng·L-1), tetracycline (13.18 ng·L-1), and sulfadiazine (4.11 ng·L-1), and the antibiotic concentration distribution showed the following order of characteristics:downstream (359.41 ng·L-1) > midstream(224.59 ng·L-1) > upstream (179.72 ng·L-1). The ecological environment risk assessment results indicated the largest risk for downstream W21, tetracycline, doxycycline, enrofloxacin, norfloxacin, and erythromycin. The risk quotient revealed that lincomycin had a medium-risk level, and ofloxacin had a high-risk level. This shows that antibiotics in the waters of the Chishui River basin may cause certain ecological risks.
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Monitoreo del Ambiente , Contaminantes Químicos del Agua , Antibacterianos/análisis , China , Medición de Riesgo , Ríos , Contaminantes Químicos del Agua/análisisRESUMEN
The association between dietary fatty acid intake and Alzheimer's disease (AD), dementia, and mild cognitive impairment (MCI) risk is inconsistent. This meta-analysis examined the effect of dietary fatty acid intake in prospective cohort studies including patients with AD, dementia, and MCI. PubMed, China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI), Wanfang Data, and VIP Database were systematically searched through September 2020. The random-effects model was used to combine the highest and lowest categories of multivariable adjusted relative risk (RR). Prospective cohort studies that included associations between dietary fatty acid intake and the risk for AD, dementia, or MCI were included. Fourteen studies were included, comprising 54 177 participants: 1696 patients with AD, 1118 patients with dementia, and 2889 with MCI. The pooled RR showed a significant association only between ω-3 polyunsaturated fatty acid (PUFA) intake and MCI risk (RR, 0.86; 95% CI, 0.75-0.98), with no heterogeneity between studies (I2 = 0%). The intake of total fatty acids, saturated fatty acids (SFAs), cholesterol, monounsaturated fatty acids (MUFAs), PUFAs, ω-3 PUFAs, ω-6 PUFAs, docosahexaenoic acids (DHAs), and eicosapentaenoic acids (EPAs) was not significantly associated with AD risk. The intake of total fatty acids, SFAs, MUFAs, PUFAs, and ω-3 PUFAs was not significantly associated with dementia risk. This meta-analysis provided evidence that ω-3 PUFA intake may be negatively associated with MCI risk.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Ácidos Grasos Omega-3 , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/etiología , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/etiología , Estudios de Cohortes , Ácidos Grasos , Humanos , Estudios ProspectivosRESUMEN
Plant growth-promoting rhizobacteria (PGPR) can potentially be used as an alternative strategy to control plant diseases. In this study, strain ST-TJ4 isolated from the rhizosphere soil of a healthy poplar was found to have a strong antifungal activity against 11 phytopathogenic fungi in agriculture and forestry. Strain ST-TJ4 was identified as Pseudomonas sp. based on 16S rRNA-encoding gene sequences. The bacterium can produce siderophores, cellulase, and protease, and has genes involved in the synthesis of phenazine, 1-phenazinecarboxylic acid, pyrrolnitrin, and hydrogen cyanide. Additionally, the volatile compounds released by strain ST-TJ4 can inhibit the mycelial growth of plant pathogenic fungi more than diffusible substances can. Based on volatile compound profiles of strain ST-TJ4 obtained from headspace collection and GC-MS/MS analysis, 1-undecene was identified. In summary, the results suggested that Pseudomonas sp. ST-TJ4 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.
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PURPOSE: While numerous epidemiological studies have indicated that omega-3 polyunsaturated fatty acids have anticancer properties in various cancers, the effects and mechanisms of eicosapentaenoic acid (EPA) in ovarian cancer cell growth are poorly understood. MATERIALS AND METHODS: ES2 ovarian clear cell carcinoma cells and SKOV3 adenocarcinoma cells were treated with palmitic acid or EPA, followed by flow cytometry and cell counting to measure apoptosis and proliferation, respectively. A modified protein lipid overlay assay was used to further verify whether EPA was a ligand of G protein-coupled receptor 30 (GPR30) in ES2 cells. The levels of apoptosis-related genes, phosphorylated AKT, and phosphorylated ERK1/2 were detected to explore the underlying mechanism. Finally, inhibitory effect of EPA on tumor growth via GPR30 was determined in vitro and in vivo. RESULTS: EPA suppressed ES2 ovarian clear cell carcinoma cells growth via GPR30, a novel EPA receptor, by inducing apoptosis. As a ligand of GPR30, EPA activated the GPR30-cAMP- protein kinase A signaling pathway. When GPR30 was suppressed by siRNA or its inhibitor G15, the antiproliferative action of EPA was impaired. Furthermore, EPA inhibited tumor growth by blocking the activation of AKT and ERK. In the mouse xenograft model, EPA decreased tumor volume and weight through GPR30 by blocking tumor cell proliferation. CONCLUSION: These results confirm that EPA is a tumor suppressor in human ovarian clear cell carcinoma cells and functions through a novel fatty acid receptor, GPR30, indicating a mechanistic linkage between omega-3 fatty acids and cancers.