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Background: Breast cancer remains a global health challenge, necessitating innovative therapeutic approaches. Immunomodulation and immunotherapy have emerged as promising strategies for breast cancer treatment. Engineered exosomes are the sort of exosomes modified with surface decoration and internal therapeutic molecules. Through suitable modifications, engineered exosomes exhibit the capability to overcome the limitations associated with traditional therapeutic approaches. This ability opens up novel avenues for the development of more effective, personalized, and minimally invasive interventions. Main body: In this comprehensive review, we explore the molecular insights and therapeutic potential of engineered exosomes in breast cancer. We discuss the strategies employed for exosome engineering and delve into their molecular mechanisms in reshaping the immune microenvironment of breast cancer. Conclusions: By elucidating the contribution of engineered exosomes to breast cancer immunomodulation, this review underscores the transformative potential of this emerging field for improving breast cancer therapy. Highlights: Surface modification of exosomes can improve the targeting specificity.The engineered exosome‐loaded immunomodulatory cargo regulates the tumour immune microenvironment.Engineered exosomes are involved in the immune regulation of breast cancer. [ABSTRACT FROM AUTHOR]

Organic chemosensors with excited‐state intramolecular proton transfer (ESIPT) behavior have attracted much attention because it has great potential in a wide range of applications. Considering the paramount behavior of excited‐state relaxation, in this work, we mainly focus on deciphering photo‐induced hydrogen bonding effects and ESIPT mechanism for the novel 2‐(benzo[d]thiazol‐2‐yl)‐4‐(9H‐carbazol‐9‐yl)phenol (mCzOH) dye. Considering the effects of different solvents on excited‐state dynamics of mCzOH flurophore, we adopt four solvents with different polarities. Analyses of fundamental structural changes, infrared (IR) vibrational spectra, and core valence partition index between S0 and S1 state, we confirm hydrogen bond OH···N of mCzOH should be enhanced via photoexcitation. Especially, the increase of solvent polarity could promote hydrogen bonding strengthening degree. Intramolecular charge transfer (ICT) resulting from photoexcitation qualitatively facilitates the ESIPT occurrence to a large extent. For further checking and probing into ESIPT mechanism, via constructing potential energy curves (PECs) in four solvents, we clarify the ESIPT behavior for mCzOH. Most worthy of mention is that polar solvent plays critical roles in lowering potential barrier of ESIPT reaction and in facilitating ESIPT process. We not only clarify the detailed excited‐state process, but also present the solvent‐polarity‐dependent ESIPT mechanism for mCzOH fluorophore. [ABSTRACT FROM AUTHOR]

Emerin is an inner nuclear envelope protein encoded by the EMD gene, mutations in which cause Emery–Dreifuss muscular dystrophy type 1 (EDMD1). Cardiac involvement has become a major threat to patients with EDMD1; however, the cardiovascular phenotype spectrums of emerinopathy and the mechanisms by which emerin regulates cardiac pathophysiology remain unclear. Here, we identified a novel nonsense mutation (c.C57G, p.Y19X) in the EMD gene in a Han Chinese family through high‐throughput sequencing. Two family members were found to have EDMD1 with muscle weakness and cardiac arrhythmia. Mechanistically, we first discovered that knockdown of emerin in HL‐1 or H9C2 cardiomyocytes lead to impaired mitochondrial oxidative phosphorylation capacity with downregulation of electron transport chain complex I and IV and upregulation of complex III and V. Moreover, loss of emerin in HL‐1 cells resulted in collapsed mitochondrial membrane potential, altered mitochondrial networks and downregulated multiple factors in RNA and protein level, such as PGC1α, DRP1, MFF, MFN2, which are involved in regulation of mitochondrial biogenesis, fission and fusion. Our findings suggest that targeting mitochondrial bioenergetics might be an effective strategy against cardiac disorders caused by EMD mutations. [ABSTRACT FROM AUTHOR]

Accumulating studies authenticate that circular RNAs (circRNAs) are involved in the progression of cancers. However, their role in breast cancer (BC) remains largely unknown. In this study, real‐time polymerase chain reaction was employed to detect the circ_0000291 and miR‐326 expressions in BC tissues and cells. The correlation between the expression level of circ_0000291 and clinicopathological parameters of BC patients was analyzed. Western blot was used to detect the expression of E26 transformation‐specific sequence‐1 (ETS1), E‐cadherin, N‐cadherin and Vimentin in BC cells. Cell proliferation was measured using the cell counting kit‐8 assay and the bromodeoxyuridine assay. Cell migration and invasion were detected by Transwell assay. The interactions between circ_0000291 and miR‐326, miR‐326 and ETS1 were verified using bioinformatics prediction, the dual‐luciferase reporter gene assay or/and RNA binding protein immunoprecipitation assay. We demonstrated that circ_0000291 was significantly upregulated in BC, and its high expression was positively correlated with T stage and local lymph node metastasis. Functional assays validated that circ_0000291 promoted BC cell proliferation, migration and invasion. The mechanism studies indicated that circ_0000291 could decoy miR‐326 and in turn upregulate the expression of ETS1. In conclusion, circ_0000291 is the novel oncogenic circRNA and promotes BC progression via modulating the miR‐326/ETS1 axis. [ABSTRACT FROM AUTHOR]

This study mainly investigates the key secondary parameter effecting on transverse force and the changing trend of its components, which include the repulsive and restoring components. Firstly, considering the transverse displacements, skin effect and end effects, the full 3D finite element models of the single‐sided linear induction motor (SLIM) are built. Secondly, when the width of the secondary varies, the transverse force and its two components are presented and analysed. At the same time, the air‐gap flux densities and the eddy currents along the transverse directions are calculated. Then when the topological transform of aluminium plate (e.g. Al‐cap type) and back‐iron plate (e.g. laminated type) are applied, the transverse force and its components are given. Finally, the transverse force, thrust and efficiencies are compared in the SLIMs with different secondaries as well as some experiments are given. It is shown that the width of the secondary is the main factor influencing the transverse force. [ABSTRACT FROM AUTHOR]

Owing to the larger total harmonic distortion (HD) of the air‐gap magnetic field in the linear induction motors with the flat‐solid and direct‐slit secondary, the construction of V‐type secondary is proposed and investigated, to reduce the harmonic components. First, a skew factor is presented to indicate the influence of the tooth harmonic on the air‐gap magnetic field. The skew distance is a key point for the design of the V‐type secondary, and the influence of the different skew distances on the thrusts, HD, and efficiencies are analysed by the three‐dimensional finite‐element method. Finally, the eddy currents, the air‐gap flux densities, and electromagnetic forces are calculated in the linear induction motors with the V‐type secondary. It shows that the V‐type secondary can reduce the harmonic components and improve the performance. [ABSTRACT FROM AUTHOR]

Due to the influence of the switch and rail equipment, the secondary cannot be laid continuously in the linear metro. An equivalent circuit of the single‐sided linear induction motor (SLIM) is presented to consider the discontinuity of the secondary plate, and the electromagnetic characteristics of the motor with the discontinuous secondary are obtained. First, the analysis model of the SLIM considering the missing part of the secondary plate is proposed. Second, the variation of the length of the coupled region between the primary and secondary are considered by the method of approximate linearisation to correct the parameters including the primary leakage inductance, magnetising inductance, secondary resistance and secondary leakage inductance. Third, three typical cases of the relative position between the primary and discontinuous secondary are analysed, and the equivalent circuit in each case is deduced according to the distribution of the secondary magnetic motive force and air gap flux density. Then, two coefficients considering the longitudinal end effect, on the basis of the corrected secondary time constant, are proposed to correct the magnetising inductance and secondary resistance. Finally, the analytical results are verified by the results measured on the test rig of an SLIM. [ABSTRACT FROM AUTHOR]

The secondary is an important design factor of single‐sided linear induction motors (SLIMs), as well as has influence on the cost and performance of SLIMs. In this study, the cap‐lamination secondary is designed and relations of the secondary parameter and performance of SLIMs are calculated. First, the aluminium (Al) cap and lamination back iron of the cap‐lamination secondary are designed and discussed. Then, improvements in performance caused by two potentially significant effects of the cap‐lamination secondary, i.e. the thick cap edge and lamination, are identified. Second, a flat‐solid secondary is applied and two SLIMs, which are the same primary and two different secondaries, are calculated by three‐dimensional finite‐element method. Eddy current densities in the Al and back iron plate, which are two parts of the secondary, are analysed. Owing to different transverse edge effects, variations of the air‐gap flux density are calculated with different secondaries. Finally, the numerical results of the thrust, power factor, and efficiency are experimentally validated by measurements on test rig of SLIMs. It shows that the SLIM with cap‐lamination secondary, which has higher performance, is affected greatly by the conductor structure of the secondary and the lamination of the iron back plate. [ABSTRACT FROM AUTHOR]

This study investigates the influence of lateral displacement of the primary on the thrust, vertical and lateral forces in a single‐side linear induction motor for linear metro. A three‐dimensional analytical model, which is able to consider the longitudinal and transversal end effects, overhang of the primary windings and lateral displacement, is developed to obtain the air‐gap flux density distributions along longitudinal and transverse directions as well as forces. Variations of the thrust, vertical and lateral forces with the lateral displacements are comprehensive investigated when the motor is torque motoring, negative sequence braking or regenerative braking operation. The analytically predicted results are experimentally validated by measurements on reciprocal power‐fed test rig. It shows that the thrust and vertical force of single‐side linear induction motor decrease almost linearly with the increase of the lateral displacement in all regions, and lateral force is restoring which helps centralising the railcar in the regenerative braking and most parts of motoring regions. [ABSTRACT FROM AUTHOR]

Electromagnetic variations of the single‐sided linear induction motor (SLIM) are calculated by three‐dimensional (3D) finite‐element method (FEM) when the primary is displaced sideways from a symmetrical position. For geometrical and electrical asymmetry, a full 3D model, which considering the longitudinal and transverse end effects, overhangs of the primary windings and secondary, as well as lateral displacement, is developed. Apart from the thrust and vertical force, lateral force is produced when the transverse asymmetry occurred. Hence, the calculation equation of thrust, vertical and lateral forces in each element of the 3D FEM model and boundary conditions are presented. Air‐gap flux densities along the longitudinal and transverse directions with different lateral displacements are obtained, as well as the distortion coefficients of the air‐gap flux density is proposed. Corresponding induced currents in the secondary are predicted. Finally, the variations of the thrust, vertical and lateral forces are experimentally validated by measurements on reciprocal power‐fed test rig. It shows that the flux in between overhangs of the primary winding and secondary has great effect on the lateral force, the thrust and vertical force decrease with the increase of the lateral displacement. [ABSTRACT FROM AUTHOR]

ABSTRACT The mechanism for the C2H3 + CH3OH reaction has been investigated by the Gaussian-4 (G4) method based on the geometric parameters of the stationary points optimized at the B3LYP/6-31G(2df, p) level of theory. Four transition states have been identified for the production of C2H4 + CH3O (TSR/P1), C2H4 + CH2OH (TSR/P2), C2H3OH + CH3 (TSR/P3), and C2H3OCH3 + H (TSR/P4) with the corresponding barriers 8.48, 9.25, 37.62, and 34.95 kcal/mol at the G4 level of theory, respectively. The rate constants and branching ratios for the two lower energy H-abstraction reactions were calculated using canonical variational transition state theory with the Eckart tunneling correction at the temperature range 300-2500 K. The predicted rate constants have been compared with existing literature data, and the uncertainty has been discussed. The branching ratio calculation suggests that the channel producing CH3O is dominant up to about 1070 K, above which the channel producing CH2OH becomes very competitive. [ABSTRACT FROM AUTHOR]

Vascularization is an important factor that affects diabetic wound healing. There is increasing evidence that myeloid cell lineages play a role in neovascularization. In this study, the efficiency of Gr-1+ CD11b+ myeloid cells to home to the site of injury and enhance diabetic wound healing by neoangiogenesis after intravenous administration was investigated. Gr-1+ CD11b+ myeloid cells were injected into tail vein after establishment of dorsal window chamber, hindlimb ischaemia and ear-punch injury in diabetic or non-diabetic mice. The Gr-1+ CD11b+ myeloid cells efficiently homed to the site of injury after intravenous administration and increased neoangiogenesis. The chemokine receptor type 4 ( CXCR4) is robustly expressed by Gr-1+ CD11b+ myeloid cells. Inhibition of CXCR4 decreases the homing ability of Gr-1+ CD11b+ myeloid cells to the site of injury, which indicates that the CXCR4/ SDF-1 axis plays an important role in the homing of Gr-1+ CD11b+ myeloid cells to the site of injury. In addition, Gr-1+ CD11b+ myeloid cells were found to improve blood flow recovery of ischaemic limb and enhance wound healing in diabetic mice by neoangiogenesis after intravenous administration. Taken together, the results of this study suggest that Gr-1+ CD11b+ myeloid cells may serve as a potential cell therapy for diabetic wound healing. [ABSTRACT FROM AUTHOR]

Copper chalcogenides have been demonstrated to be a promising photothermal agent due to their high photothermal conversion efficiency, synthetic simplicity, and low cost. However, the hydrophobic and less biocompatible characteristics associated with their synthetic processes hamper widely biological applications. An alternative strategy for improving hydrophilicity and biocompatibility is to coat the copper chalcogenide nanomaterials with silica shell. Herein, the rational preparation design results in successful coating mesoporous silica (mSiO2) on as-synthesized Cu9S5 nanocrystals, forming Cu9S5@mSiO2-PEG core-shell nanostructures. As-prepared Cu9S5@mSiO2-PEG core-shell nanostructures show low cytotoxicity and excellent blood compatibility, and are effectively employed for photothermal ablation of cancer cells and infrared thermal imaging. Moreover, anticancer drug of doxorubicin (DOX)-loaded Cu9S5@mSiO2-PEG core-shell nanostructures show pH sensitive release profile and are therefore beneficial to delivery of DOX into cancer cells for chemotherapy. Importantly, the combination of photothermal- and chemotherapies demonstrates better effects of therapy on cancer treatment than individual therapy approaches in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are studied for their potential clinical use in regenerative medicine, tissue engineering and tumour therapy. However, the therapeutic application of MSCs in tumour therapy still remains limited unless the immunosuppressive role of MSCs for tumour growth in vivo is better understood. In this study, we investigated the mechanism of MSCs favouring tumour escape from immunologic surveillance in inflammatory microenvironment. We first compared the promotive capacity of bone marrow-derived MSCs on B16 melanoma cells growth in vivo, pre-incubated or not with the inflammatory cytokines interferon (IFN)-γ and tumour necrosis factor (TNF)-α. We showed that the development of B16 melanoma cells is faster when co-injected with MSCs pre-incubated with IFN-γ and TNF-α compared with control groups. Moreover, tumour incidence increases obviously in allogeneic recipients when B16 melanoma cells were co-injected with MSCs pre-incubated with IFN-γ and TNF-α. We then demonstrated that the immunosuppressive function of MSCs was elicited by IFN-γ and TNF-α. These cytokine combinations provoke the expression of inducible nitric oxide synthase (iNOS) by MSCs. The impulsive effect of MSCs treated with inflammatory cytokines on B16 melanoma cells in vivo can be reversed by inhibitor or short interfering RNA of iNOS. Our results suggest that the MSCs in tumour inflammatory microenvironment may be elicited of immunosuppressive function, which will help tumour to escape from the immunity surveillance. [ABSTRACT FROM AUTHOR]

BSTRACT For the food safety of sea products, the variables of headspace solid-phase microextraction (HS-SPME) and supercritical fluid extraction (SFE) were optimized for the determination of organotin compounds in clam samples by method of off-line SFE/HS-SPME and gas chromatographic analysis with mass spectrometry (GC-MS). The best result was obtained while the spiked clam sample was extracted at 45C and 30 MPa with carbon dioxide modified with 5% (mol) methanol at 1.2 L/min (as carbon dioxide in ambient pressure) for 15 min, and SFE extract was ethylated with 2% (w/v ) sodium tetraethylborate (NaBEt4) in pH 4 buffer solution and simultaneously adsorbed by HS-SPME with polydimethylsiloxane-divinylbenzene (PDMS/DVB) fiber at 50C for 30 min, followed by GC-MS. The whole sampling and analyzing process was within 1 h, and only less than 10 mL of solvent were used. The results were comparable with those obtained by traditional method which use of methanol (contain 0.03% tropolone), and the procedure also seems to be less time- and labor-consuming. The pollution of OTCs in seafood indicated a potential danger for the health of the local people who cared for these foods. PRACTICAL APPLICATIONS The present investigation was carried out to optimize the method for the determination of organotin compounds in sea products. Organotin compounds (OTCs) was widely used in antifouling painting, which has been the most important pollution in marine environment. The sea products contaminated by the OTCs became a great problem on the food safety. Using this method for the determination of organotin compounds in sea products, the whole sampling and analyzing process was within 1 h, and only less than 10 mL of solvent were used. This method was a rapid and green method for monitoring the organotin pollution of sea products. [ABSTRACT FROM AUTHOR]

Although much effort has been extended to the efficient cancer therapies, the drug resistance is still a major obstacle in cancer chemotherapeutic treatments. Almost 90% of the cancer therapy failure is caused by the relative problems. Recently, the application of drug coated polymer nanospheres and nanoparticles to inhibit the related drug resistance has attracted much attention. In this report, we have explored a novel strategy to inhibit the multidrug resistance of the targeted tumor cells by combining the unique properties of tetraheptylammonium capped Fe3O4 magnetic nanoparticles with the drug accumulation of anticancer drug daunorubicin. Our results of confocal fluorescence and atomic force microscopy (AFM) as well as electrochemical studies demonstrate the remarkable synergistic effect of Fe3O4 nanoparticles on drug uptake of daunorubicin in leukemia K562 cells. These observations indicate that the interaction between the magnetic nanoparticles Fe3O4 and biologically active molecules on the membrane of leukemia cell lines may contribute to their beneficial effect on cellular uptake so that the synergistic enhanced effect of magnetic nanoparticles Fe3O4 on drug uptake of drug resistance leukemia K562 cells could be observed upon application of the Fe3O4 nanoparticles. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006 [ABSTRACT FROM AUTHOR]

The size of dislocation rosettes introduced by indentation in the temperature range from 300 to 773 K are studied. The dislocation velocity and its temperature dependence are estimated. It is shown that the activation energy of dislocation movement at temperatures lower than 773 K does not exceed 1 eV. [ABSTRACT FROM AUTHOR]

Twenty primiparous sows were allocated to two treatments to evaluate the effects of maternal 25-hydroxycholecalciferol (25OHD3) supplementation during gestation and lactation on milk quality and serum bone status markers of sows and bone quality of piglets. Immediately after mating, sows were randomly allotted to one of two diets supplemented with 50 µg/kg 25OHD3 or basal diets without 25OHD3. Blood and milk samples were obtained. At birth and weaning, 10 piglets from each treatment were killed for bone quality analysis. 25OHD3-fed sows provided one more piglet at farrowing and 1.17 more piglets at weaning than sows fed basal diets. The contents of solids not-fat, protein, fat or lactose were increased in milk from days 7 and 14 of lactation in 25OHD3-supplemented sows and 25OHD3 concentrations in milk were increased by dietary 25OHD3 supplementation. Dietary 25OHD3 supplementation increased serum alkaline phosphatase activity but had no effect on serum tartrate-resistant acid phosphatase activity of sows. Maternal 25OHD3 supplementation improved bone strength, density and ash content of newborn piglets rather than those of weaning piglets. In conclusion, 25OHD3 supplementation in maternal diets improved reproductive performance, milk quality and bone status of sows as well as bone quality of newborn piglets. [ABSTRACT FROM AUTHOR]