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Breast cancer is known as the most prevalent cancer in women worldwide, and has an undeniable negative impact on public health, both physically, and mentally. This study aims to investigate the effects of toll‐like receptor 4 (TLR4) gene silencing on proliferation and apoptosis of human breast cancer cells to explore for a new theoretical basis for its treatment. TLR4 small interference RNA (siRNA) fragment recombinant plasmids were constructed, including TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3. Human breast cancer MCF‐7 and MDA‐MB‐231 cells were assigned into blank, negative control (NC), TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3 groups. MCF‐7 and MDA‐MB‐231 cell growth was detected by MTT assay. Apoptosis and cell cycle were determined by flow cytometry. Reverse transcription quantitative polymerase chain reaction (RT‐qPCR) and Western blot analysis were conducted to determine the expression of TLR4, CDK4, cyclin D1, Livin, Bcl‐2, p53, c‐FLIP, and caspase‐3. In comparison with the NC and blank groups, the TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3 groups showed decreased the expression of TLR4, inhibited proliferation of MCF‐7 and MDA‐MB‐231 cells and promoted MCF‐7 and MDA‐MB‐231 cell apoptosis, and the cells were blocked in G1 phase. In comparison with the NC and blank groups, in the TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3 groups, siRNA‐TLR4 significantly increased expression of p53 and caspase‐3 in MCF‐7 and MDA‐MB‐231 cells, while it decreased the expressions of CDK4, cyclinD1, Livin, Bal‐2, and c‐FLIP. The study demonstrates that TLR4 gene silencing inhibits proliferation and induces apoptosis of MCF‐7 and MDA‐MB‐231 cells. TLR4 gene silencing inhibits proliferation and induces apoptosis of MCF‐7 and MDA‐MB‐231 cells. [ABSTRACT FROM AUTHOR]

Sepsis, as a systemic inflammatory response syndrome (SIRS) subtype, is generally characterized by infection. Emerging evidence has highlighted dysregulated microRNAs (miRNAs) are involved in the progression of sepsis. The aim of the study was to investigate the effects of miR-335-5p on inflammatory responses in a septic mouse model. The hypothesis was subsequently asserted that the FASN gene and AMPK/ULK1 signaling pathway may participate in the regulation of miR-335-5p. A septic mouse model was established in order to validate the effect of miR-335-5p on the inflammatory response by means of suppressing the endogenous expression of FASN by siRNA against FASN in endothelial cells. A target prediction program and luciferase activity was employed to ascertain as to whether miR--335-5p targets FASN. The levels of inflammatory factors including IL-6 and IL-1β were determined by means of ELISA assay. RT-qPCR and western blot analysis were used to determine the AMPK/ULK1 signaling pathway-, apoptosis- and autophagy-related genes. Flow cytometry was employed in order to evaluate sepsis-induced cell apoptosis in response to miR-335-5p and FASN alternations. FASN was identified as a target gene of miR--335-5p. Gain- and loss-of-function studies revealed that miR-335-5p acted to enhance autophagy, reduce cell apoptosis, promote cell cycle entry in endothelial cells, and reduce inflammatory response through the modulation of pro- and anti-apoptotic factors in endothelial cells. The effect of miR-335-5p on endothelial cells was increased when FASN was suppressed by siRNA as well as when the AMPK/ULK1 signaling pathway was activated, suggesting that miR-335-5p influences sepsis by targeting and inhibiting FASN, and activating the AMPK/ULK1 signaling pathway. Our study provides evidence indicating that overexpressed miR-335-5p enhances autophagy by targeting FASN through activation of the AMPK/ULK1 signaling pathway working to alleviate the inflammatory response in septic mouse models, emphasizing the value of the functional upregulation of miR-335-5p as therapeutic strategy for sepsis. [ABSTRACT FROM AUTHOR]

Polyoxymethylene (POM)/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane (TPU) and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3 content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3 particles. [ABSTRACT FROM AUTHOR]

Background: Depression is two-to-three times more frequent among women. The hypothalamus, a sexually dimorphic area, has been implicated in the pathophysiology of depression. Neuroinflammation-induced hypothalamic dysfunction underlies behaviors associated with depression. The lipopolysaccharide (LPS)-induced mouse model of depression has been well-validated in numerous laboratories, including our own, and is widely used to investigate the relationship between neuroinflammation and depression. However, the sex-specific differences in metabolic alterations underlying depression-associated hypothalamic neuroinflammation remain unknown. Methods: Here, we employed the LPS-induced mouse model of depression to investigate hypothalamic metabolic changes in both male and female mice using a metabolomics approach. Through bioinformatics analysis, we confirmed the molecular pathways and biological processes associated with the identified metabolites. Furthermore, we employed quantitative real-time PCR, enzyme-linked immunosorbent assay, western blotting, and pharmacological interventions to further elucidate the underlying mechanisms. Results: A total of 124 and 61 differential metabolites (DMs) were detected in male and female mice with depressive-like behavior, respectively, compared to their respective sex-matched control groups. Moreover, a comparison between female and male model mice identified 37 DMs. We capitalized on biochemical clustering and functional enrichment analyses to define the major metabolic changes in these DMs. More than 55% of the DMs clustered into lipids and lipid-like molecules, and an imbalance in lipids metabolism was presented in the hypothalamus. Furthermore, steroidogenic pathway was confirmed as a potential sex-specific pathway in the hypothalamus of female mice with depression. Pregnenolone, an upstream component of the steroid hormone biosynthesis pathway, was downregulated in female mice with depressive-like phenotypes but not in males and had considerable relevance to depressive-like behaviors in females. Moreover, exogenous pregnenolone infusion reversed depressive-like behaviors in female mice with depression. The 5α-reductase type I (SRD5A1), a steroidogenic hub enzyme involved in pregnenolone metabolism, was increased in the hypothalamus of female mice with depression. Its inhibition increased hypothalamic pregnenolone levels and ameliorated depressive-like behaviors in female mice with depression. Conclusions: Our study findings demonstrate a marked sexual dimorphism at the metabolic level in depression, particularly in hypothalamic steroidogenic metabolism, identifying a potential sex-specific pathway in female mice with depressive-like behaviors. [ABSTRACT FROM AUTHOR]

Background: IFN-λ has been shown to have a dual function in cancer, with its tumor-suppressive roles being well-established. However, the potential existence of a negative "tumor-promoting" effect of endogenous IFN-λ is still not fully understood. Methods: We conducted a comprehensive review and analysis of the perturbation of IFN-λ genes across various cancer types. Correlation coefficients were utilized to examine the relationship between endogenous IFN-λ expression and clinical factors, immune cell infiltration, tumor microenvironment, and response to immunotherapy. Genes working together with IFN-λ were obtained by constructing the correlation-based network related to IFN-λ and the gene interaction network in the KEGG pathway and IFN-λ-related genes obtained from the networks were integrated as candidate markers for the prognosis model. We then applied univariate and multivariate COX regression models to select cancer-specific independent prognostic markers associated with IFN-λ and to investigate risk factors for these genes by survival analysis. Additionally, computational methods were used to analyze the transcriptome, copy number variations, genetic mutations, and methylation of IFN-λ-related patient groups. Result: Endogenous expression of IFN-λ has been linked to poor prognosis in cancer patients, with the genes IFN-λ2 and IFN-λ3 serving as independent prognostic markers. IFN-λ acts in conjunction with related genes such as STAT1, STAT2, and STAT3 to affect the JAK-STAT signaling pathway, which promotes tumor progression. Abnormalities in IFN-λ genes are associated with changes in immune checkpoints and immune cell infiltration, which in turn affects cancer- and immune-related pathways. While there is increased immune cell infiltration in patients with IFN-λ expression, this does not improve survival prognosis, as T-cell dysfunction and an inflammatory environment are also present. The amplification of IFNL2 and IFNL3 copy number variants drives specific endogenous expression of IFN-λ in patients, and those with this specific expression have been found to have more mutations in the TP53 gene and lower levels of DNA methylation. Conclusion: Our study integrated multi-omics data to provide a comprehensive insight into the dark side of endogenous IFN-λ, providing a fundamental resource for further discovery and therapeutic exploration in cancer. [ABSTRACT FROM AUTHOR]

In recent years, lipid-coated calcium-phosphate (LCP) nanoparticle has been developed as a versatile platform for delivery of various therapeutics including gene, protein/peptide, chemotherapeutics and theranostic agents. The high endosomal escape, coupled with the ability to efficiently encapsulate phosphorylated drugs or prodrugs, make LCP become attractive vehicle for drug delivery. Additionally, the principle behind LCP formulation has also allowed rational design of LCP-derived nanoparticles (NPs) with other solid core or lipid membrane to overcome the various drug delivery barriers. Here, we briefly review the history of the development of LCP NPs, highlight the optimisations and modulations in the development process, and summarise the major applications of LCP NPs and LCP-derived NPs in drug delivery. [ABSTRACT FROM AUTHOR]

Background: Ribosomal protein S6 kinase 1 (S6K1) is a serine–threonine kinase that has two main isoforms: p70S6K (70-kDa isoform) and p85S6K (85-kDa isoform). p70S6K, with its upstream mammalian target of rapamycin (mTOR), has been shown to be involved in learning and memory and participate in the pathophysiology of Alzheimer's disease (AD). However, the function of p85S6K has long been neglected due to its high similarity to p70S6k. The role of p85S6K in learning and memory is still largely unknown. Methods: We fractionated the postsynaptic densities to illustrate the differential distribution of p85S6K and p70S6K. Coimmunoprecipitation was performed to unveil interactions between p85S6K and the GluA1 subunit of AMPA receptor. The roles of p85S6K in synaptic targeting of GluA1 and learning and memory were evaluated by specific knockdown or overexpression of p85S6K followed by a broad range of methodologies including immunofluorescence, Western blot, in situ proximity ligation assay, morphological staining and behavioral examination. Further, the expression level of p85S6K was measured in brains from AD patients and AD model mice. Results: p85S6K, but not p70S6K, was enriched in the postsynaptic densities. Moreover, knockdown of p85S6K resulted in defective spatial and recognition memory. In addition, p85S6K could interact with the GluA1 subunit of AMPA receptor through synapse-associated protein 97 and A-kinase anchoring protein 79/150. Mechanistic studies demonstrated that p85S6K could directly phosphorylate GluA1 at Ser845 and increase the amount of GluA1 in synapses, thus sustaining synaptic function and spine densities. Moreover, p85S6K was found to be specifically decreased in the synaptosomal compartment in the brains of AD patients and AD mice. Overexpression of p85S6K ameliorated the synaptic deficits and cognitive impairment in transgenic AD model mice. Conclusions: These results strongly imply a significant role for p85S6K in maintaining synaptic and cognitive function by interacting with GluA1. The findings provide an insight into the rational targeting of p85S6K as a therapeutic potential for AD. [ABSTRACT FROM AUTHOR]

Nymphaea stellata willd. flowers (NSF) are used as a traditional medicine in India and Nepal to treat diabetic disease. Different works have demonstrated that NSF extract showed antihyperglycemic effect on alloxan-induced diabetic rats. In the present work we evaluated in vitro intestinal α-glucosidase inhibition as the possible mode of action of NSF extract on suppressing postprandial hyperglycemia for curing diabetic mellitus. In addition, NSF extract was studied to assess its possible acute oral toxicity and genotoxicity. Materials and methods: Rat intestinal crude enzyme preparation and Caco-2 monolayer were used to evaluate α-glucosidase inhibitory activity of NSF extract. The main α-glucosidase inhibitors were detected by HPLC. For acute toxicity test, NSF extract was administered at doses of 2000, 5000 and 10,000mg/kg body to three groups of 10 ICR mice each, and then clinical symptoms including mortality, clinical sign and gross findings were observed once a day for 14 days. In Ames test, histidine-dependent auxotrophic mutants of Salmonella typhimurium (strains TA97, TA98, TA100, TA102 and TA1535) were used and incubated in the presence and absence of S9 metabolic activation using NSF extract with concentrations of 150–5000μg/plate. The chromosome aberration test was conducted with Chinese hamster lung (CHL) cells treated with NSF extract at doses of 150–5000μg/ml in the presence and absence of S9 metabolic activation. In the in vivo mouse micronucleus assay, 9-week-old male and female ICR mice (n =90, 25–30g) were administered daily by oral gavage at doses of 2.5, 5.0 and 10.0g/kg body for 1 or 2 days. Bone marrow smears were prepared from each treatment group 24h after last administration and then polychromatic erythrocytes (PCEs) and normochromatic erythrocytes (NCEs) were identified. Results: NSF extract showed potent rat intestinal α-glucosidase inhibitory activity for maltose hydrolysis with ED50 value of 0.1mg/ml. In Caco-2 monolayer, α-glucosidase activity for the maltose hydrolysis was down-regulated by NSF extract at a concentration of 0.05mg/well level, showing 74% inhibition compared to the saline treated control. NSF was rich in phenol contents and the main α-glucosidase inhibitor, 1,2,3,4,6-penta-O-galloyl-β-d-glucose, was identified together with two phenolic compounds of gallic acid and corilagin. In acute toxicity test, NSF extract did not produce any toxic signs or deaths and the LD50 value of this extract could be greater than 10,000mg/kg body weight. These results of genotoxicity assessment showed that NSF extract did not cause genotoxic effects in Ames test, in the in vitro chromosomal aberration assay and in the in vivo micronucleus assay. Conclusion: The current study shows that the extract from Nymphaea stellata flowers exhibits significant intestinal α-glucosidase inhibitory activity, without showing any acute toxicity or genotoxicity, which may be useful in suppressing postprandial hyperglycemia in diabetics. The results presented here suggest that the use of NSF in folk medicine as a natural antidiabetic treatment could be safe as well as beneficial. [Copyright &y& Elsevier]

Ethylene propylene diene monomer (EPDM) compounds with good flame-retardant and γ-ray radiation resistant properties were prepared by adding complex flame retardants and phenathrene. The resultant EPDM formulations have a long time to ignition (TTI >46 s), a low peak heat release rate (PHRR~341 kW/m 2 ) and a high limited oxygen index (LOI >30). Effects of γ-ray radiation on the resultant flame-retardant EPDM was investigated. The formulated EPDM is a crosslinking dominated polymer under γ-ray radiation. The γ-ray radiation resistant property of EPDM was enhanced by adding phenanthrene. Elongation at break of EPDM formulated with phenanthrene could retain 91% after being irradiated to 0.3 MGy and still retains 40% elongation even after being irradiated to 0.9 MGy, which is much better the control. It is expected that the formulated flame-retardant and radiation resistant EPDM materials could meet the requirements for use in radiation environments. [ABSTRACT FROM AUTHOR]

In this work, different contents of graphene oxide (GO) were introduced into poly(butylene succinate) (PBS) to study the effects of GO on crystallization of PBS matrix and the resultant hydrolytic degradation behaviors of the PBS/GO composites. The initial crystalline structures of PBS in the composites were investigated using a polarized optical microscope (POM), differential scanning calorimetry (DSC) and a wide angle X-ray diffraction (WAXD). The results demonstrated that GO showed nucleation effect for the crystallization of PBS matrix. However, high content of GO also restricted the growth of crystallite, resulting in the decrease of PBS crystallinity and the reduction of crystal size. The hydrophilicity of sample was evaluated by measuring the contact angle of water on the sample surface. The results demonstrated that the presence of GO greatly enhanced the hydrophilicity of the sample. The hydrolytic degradation behavior of sample in alkaline solution was investigated at 37 °C. The results showed that the hydrolytic degradation ability of PBS was greatly enhanced by adding GO. The more the GO in the composites, the higher the hydrolytic degradation ability was. The increased hydrophilicity that enhanced the wettability of sample surface by water, the decreased crystallinity of PBS matrix, and the presence of the defects in the composite, e. g. at the interface between the PBS matrix and GO particles, mainly contributed to the largely enhanced hydrolytic degradation ability of PBS. The microstructure changes during the hydrolytic degradation process were also analyzed. This work provided an alternative way to accelerate the hydrolytic degradation of PBS. [ABSTRACT FROM AUTHOR]

Background and purpose As a molecular chaperone, acetylcholinesterase ( ACh E; EC 3.1.1.7) plays a critical role in the pathogenesis of Alzheimer's disease ( AD). The peripheral anionic site ( PAS) of ACh E has been indicated as the amyloid-β (Aβ) binding domain. The goal of this study was to determine other motifs in ACh E involved in Aβ aggregation and deposition. Methods and results The β-hairpin in monomeric Aβ is the key motif of nucleation-dependent Aβ self-aggregation. As ACh E could induce Aβ aggregation and deposition, we searched ACh E for β-hairpin structures. In A11-specific dot blot assay, ACh E was detected by an oligomer-specific antibody A11, implying the existence of β-hairpin structures in ACh E as β-hairpin was the core motif of oligomers. A molecular superimposing approach further revealed that the N-terminal region, from Glu7 to Ile20, in ACh E ( ACh E 7-20) was similar to the β-hairpin domain in Aβ. The results of further dot blot assays, thioflavin T fluorescence assays, and electron microscopy imaging experiments, indicated that the N-terminal synthetic peptide ACh E7-20 had nearly the same ability as ACh E with regard to triggering Aβ aggregation and deposition. Conclusions ACh E 7-20, a β-hairpin region in ACh E, might be a new motif in ACh E capable of triggering Aβ aggregation and deposition. This finding will be helpful to design new and more effective Aβ aggregation inhibitors for AD treatment. [ABSTRACT FROM AUTHOR]

A simple, rapid and sensitive high-performance liquid chromatographic (HPLC) method has been developed to quantify zolmitriptan in plasma using an isocratic system with fluorescence detection. The method included a single-step liquid–liquid extraction with methyl tertiary butyl ether. HPLC separation was carried out by reversed phase chromatography with a mobile phase composed of 0.05% (v/v) triethylamine in water(adjusting to pH 2.75 with 85% phosphoric acid) and acetonitrile (92:8, v/v), pumped at flow rate of 1.5 ml/min. Fluorescence detection was performed at 225 nm (excitation) and 360 nm (emission). The calibration curve for zolmitriptan was linear from 0.2 to 40 ng/ml. The validation method yielded good results regarding linearity, precision, accuracy, specificity and recoveries. The values of the limit of detection (LOD) and limit of quantification (LOQ) were 20 and 40 pg, respectively. The method was sensitive, simple and repeatable enough to be used in pharmacokinetic studies. [Copyright &y& Elsevier]

As a part of long-term project aimed at super polyolefin blends, in this work, we report the mechanical reinforcement and phase morphology of the immiscible blends of polypropylene (PP) and polystyrene (PS) achieved by dynamic packing injection molding (DPIM). The shear stress (achieved by DPIM) and interfacial interaction (obtained by using styrene–butadiene–styrene (SBS) as a compatibilizer) have a great effect on phase morphology thus mechanical properties. The shear-induced morphology with core in the center and oriented zone surrounding the core was observed in the cross-section areas of the samples. The phase inversion was also found to shift towards lower PS content under shear stress, at 70 wt% in the core and 30 wt% in the oriented zone, compared with 80 wt% for static samples (without shear). The tensile strength, tensile modules and impact strength were found largely increase by means of either shear stress or compatibilizer. The PS particle size is greatly reduced with adding of SBS, and the reduced particle size results in greater resistance to deformation, which causes the co-continuous structure at oriented zone change into droplet morphology. The morphology resulting from blending and processing was discussed based on effect of interfacial tension, shear rate, phase viscosity ratio and composition. The observed change of mechanical properties was explained based on the combined effect of phase morphology (droplet-matrix or co-continuous phase) and molecular orientation under shear stress. [Copyright &y& Elsevier]