Polydopamine nanoplatform with near infrared light and pH dual stimuli-responsive for chemo-photothermal cancer therapy.

Photothermal agent accompanying with thermally responsive materials, displays well controlled drug release property, which is well-received as an outstanding design strategy for simultaneous photothermal/chemotherapy in cancer. Cyanine dye, as the prestigious photothermal agent has shown great potential due to its preeminent near-infrared absorbance and excellent thermal conversion efficiency. However, their inherent defect such as inferior photothermal stability, high leakage risk and poor therapy efficacy limit their further application in cancer therapy. Hence, a facile and universal strategy to make up these deficiencies is developed. Chemotherapeutic drug DOX and cyanine dye were loaded into polydopamine (PDA) nanoparticles. The PDA encapsulation dramatically improved the photothermal stability of cyanine dye. Attributed by the PDA structure feature, the thermo-sensitive small molecule glyamine (Gla) is introduced into the PDA surface to lessen leakage. The Gla can form a dense encapsulation layer on the dopamine surface through hydrogen bond. This newly fabricated Cyanine/DOX@PDA-Gla nanopaltform is characterized with NIR light/pH dual-responsive property, high NIR photothermal conversion performance and fluorescence guided chemo-photothermal therapy.

Zinc Ameliorates Tripterygium Glycosides-Induced Reproductive Impairment in Male Rats by Regulating Zinc Homeostasis and Expression of Oxidative Stress-Related Genes.

Tripterygium glycosides (TG) can seriously damage male reproductive function, and the reproductive system is difficult to restore after stopping the administration of TG in male rats. Zinc (Zn) is one of the most important trace elements in the human body and plays an important role in maintaining male fertility. The aim of this study was to investigate whether zinc supplementation could improve the testicular reproductive damage induced by TG toxicity in rats and to investigate its mechanism of action. The results showed that zinc sulfate (ZnSO4) could improve testicular tissue structure and semen parameters, promote testosterone synthesis, increase zinc-containing enzyme activity, increase zinc concentration in serum and testicular tissues, and maintain zinc homeostasis in male rats induced by TG toxicity. Zinc supplementation activated relevant signalling molecules in the KEAP1-NRF2/ARE pathway and alleviated TG-induced oxidative stress. Therefore, this study concluded that zinc supplementation could improve reproductive damage by regulating zinc homeostasis and the expression of genes related to oxidative stress.

Clinical Application of Matrix-Assisted Laser-Resolved Ionization Time-Of-Flight Mass Spectrometry for Rapid Detection of Blood-Borne Pathogens.

Objective: To evaluate the performance of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) in the identification of clinical pathogenic microorganisms. Methods: Blood culture-positive specimens were collected from inpatients in our hospital from March to December 2022 and identified using VITEK 2XL (biochemical), VITEK MS (colony), VITEK MS (bacterial membrane) and VITEK MS (separating gel) methods, respectively, to compare the compliance rate and identification values of the four methods. Results: A total of 280 strains were included in the analysis, including 155 (55.36%) Gram-negative and 125 (44.64%) Gram-positive strains. 279 (99.64%) of the 280 strains were identified by VITEK 2XL (biochemical), including 154 (99.35%) Gram-negative and 125 (100%) Gram-positive strains. VITEK MS (colony) identified 278 (99.29%) strains, including 153 (98.71%) Gram-negative and 125 (100%) Gram-positive. 261 (93.21%) strains were identified in VITEK MS (bacterial membrane), including 148 (95.48%) Gram-negative and 113 (90.40%) Gram-positive strains. VITEK MS (separating gel) identified 232 (82.86%) strains, including 136 (87.74%) Gram-negative and 96 (76.80%) Gram-positive strains. Conclusion: MALDI-TOF MS findings are highly consistent with traditional culture identification methods in terms of identification accuracy, and the VITEK MS (bacterial membrane) and VITEK MS (separating gel) identification methods significantly reduce the turnaround time for identification in the laboratory.

Performance improvement of three-body radiative diodes driven by graphene surface plasmon polaritons.

As an analogue to an electrical diode, a radiative thermal diode allows radiation to transfer more efficiently in one direction than in the opposite direction by operating in a contactless mode. In this study, we demonstrated that within the framework of three-body photon thermal tunneling, the rectification performance of a three-body radiative diode can be greatly improved by bringing graphene into the system. The system is composed of three parallel slabs, with the hot and cold terminals of the diode coated with graphene films and the intermediate body made of vanadium dioxide (VO2). The rectification factor of the proposed radiative thermal diode reaches 300% with a 350 nm separation distance between the hot and cold terminals of the diode. With the help of graphene, the rectification performance of the radiative thermal diode can be improved by over 11 times. By analyzing the spectral heat flux and energy transmission coefficients, it was found that the improved performance is primarily attributed to the surface plasmon polaritons (SPPs) of graphene. They excite the modes of insulating VO2 in the forward-biased scenario by forming strongly coupled modes between graphene and VO2 and thus dramatically enhance the heat flux. However, for the reverse-biased scenario, the VO2 is at its metallic state, and thus, graphene SPPs cannot work by three-body photon thermal tunneling. Furthermore, the improvement was also investigated for different chemical potentials of graphene and geometric parameters of the three-body system. Our findings demonstrate the feasibility of using thermal-photon-based logical circuits, creating radiation-based communication technology and implementing thermal management approaches at the nanoscale.

SALL4 activates PI3K/AKT signaling pathway through targeting PTEN, thus facilitating migration, invasion and proliferation of hepatocellular carcinoma cells.

This study aims to explore the specific mechanisms of SALL4 on the migration, invasion and proliferation of HCC. HepG2 and SMMC-7721 cells were transfected with SALL4 NC, mimics and inhibitors. The proliferation capability and cell cycle progression of HCC cells were detected through CCK8 assay and flow cytometry, and their migration and invasion capabilities were detected by wound healing assay and Transwell assay. In SALL4 inhibitor NC group and SALL4 inhibitor group, the PTEN inhibitor SF1670 was added, and the expression levels of PI3K/AKT, migration, invasion and proliferation-related proteins were detected by Western blotting. Results showed that after up-regulation of SALL4, the migration distance of HCC cells increased, the numbers of migrated cells and the number of colonies formed significantly rosed, and there were fewer cells in G1 phase but significantly more cells in S phase, thereby down-regulation of SALL4, the opposite results. The results of Western blotting revealed that after SF1670, the specific PTEN inhibitor was added in SALL4 inhibitor group and SALL4 inhibitor NC group, the protein expression of PTEN in HCC cells significantly declined, while the protein expressions of p-PI3K, p-AKT, MMP2, MMP9, CyclinD, CyclinA1, PCNA and P62 significantly rose. In conclusion, SALL4 activates the PI3K/AKT signaling pathway through targeting PTEN, thereby facilitating the migration, invasion and proliferation of HCC cells.

Development of field-applicable endogenous internally controlled recombinase-aided amplification (EIC-RAA) assays for the detection of human papillomavirus genotypes 6 and 11 using sample releasing agent.

Objective: Human papillomavirus (HPV) 6 and 11 are the two most common low-risk HPV subtypes, accounting for more than 90% of condyloma acuminatum. A simple, accurate and rapid screening method to be applied in community-level hospitals is in high demand. Methods: Endogenous internally controlled recombinase-assisted amplification (EIC-RAA) assays for HPV6 and 11 were performed in a single closed-tube at 39 °C within 30 min. The sensitivity and specificity of EIC-RAA were examined using recombinant plasmids and pre-tested HPV DNA. A total of 233 clinical samples were collected, and the DNA was extracted by traditional multi-step extraction, or sample releasing agent, before analysis by EIC-RAA. For comparison, HPV detection via Quantitative real-time PCR (qPCR) was also performed. Results: The sensitivity of EIC-RAA analysis was 10 copies/reaction for HPV6, 100 copies/reaction for HPV11, and 100 copies/reaction for the human ß-globin gene. No cross-reaction was observed with other HPV subtypes. Clinical performance of the EIC-RAA assay achieved a 100% of concordance rate with the commercial HPV qPCR kit. Further, the EIC-RAA assay achieved a 100% of concordance rate when using multi-step extracted DNA and sample releasing agent-processed DNA. Summary: The EIC-RAA assay for HPV6 and 11 detection possesses the advantages of accuracy, simplicity and rapidity, and demonstrates great potential to be used in community-level hospitals for field investigation.

Lattice Boltzmann modeling of two-phase electrohydrodynamic flows under unipolar charge injection.

In this work, a two-dimensional droplet confined between two parallel electrodes under the combined effects of a nonuniform electric field and unipolar charge injection is numerically investigated using the lattice Boltzmann method (LBM). Under the non-Ohmic regime, the interfacial tension and electric forces at the droplet surface cooperate with the volumetric Coulomb force, leading to complex deformation and motion of the droplet while at the same time inducing a bulk electroconvective flow. After we validate the model by comparing with analytical solutions at the hydrostatic state, we perform a quantitative analysis on the droplet deformation factor D and bulk flow stability criteria T_{c} under different parameters, including the electric capillary number Ca, the electric Rayleigh number T, the permittivity ratio ɛ_{r}, and the mobility ratio K_{r}. It is found that the bulk flow significantly modifies the magnitude of D, which in turn decreases T_{c} of the electroconvective flow. For a droplet repelled by the anode, ɛ_{r}>1, an interesting linear relationship can be observed in the D-Ca curves. However, for a droplet attracted to the anode, ɛ_{r}<1, the system is potentially unstable. After first evolving into a quasisteady state, the droplet successively experiences steady flow, periodic flow, second steady flow, and oscillatory flow with increasing T. Moreover, discontinuities can be observed in the D-T curves due to the transitions of bulk flow.

Development of a duplex recombinase-aided amplification assay for direct detection of Mycoplasma pneumoniae and Chlamydia trachomatis in clinical samples.

BACKGROUND: Pneumonia caused by Mycoplasma pneumoniae is common in the elderly and children, and pneumonia caused by Chlamydia trachomatis is prevalent in newborns. This study aimed to establish a rapid, sensitive, and simple method for the direct detection of M. pneumoniae and C. trachomatis in clinical samples without DNA extraction. METHODS: We established a duplex recombinase-aided amplification (RAA) assay with the RNAseP gene as an internal control for detecting the P1 gene of M. pneumoniae and the ORF8 gene of C. trachomatis, respectively. The results were obtained at 39 °C within 15-20 min. A total of 130 clinical samples suspected of M. pneumoniae or C. trachomatis infection were collected and tested by duplex RAA and PCR. DNA extracted via a commercial kit or treated with a nucleic acid-releasing agent was used and compared, respectively. Standard recombinant plasmids were used to test the sensitivity of the duplex RAA assay. In addition, other similar common pathogens were used to verify the specificity of the duplex RAA assay. RESULTS: The sensitivity of the duplex RAA assay for detecting M. pneumoniae and C. trachomatis was 10 copies/µL using recombinant plasmids. Compared with PCR, the sensitivity and specificity of duplex RAA assays for M. pneumoniae and C. trachomatis was 100% using clinical DNA samples extracted using a commercial kit and a nucleic acid-releasing agent, and the Kappa value was 1. CONCLUSION: The advantages of this duplex RAA assay include high sensitivity and specificity, short duration, and simple extraction steps, with potential for use in the on-site detection of M. pneumoniae and C. trachomatis in resource-limited settings.

Rapid Internal Control Reference Recombinase-Aided Amplification Assays for EBV and CMV Detection.

Epstein-Barr virus (EBV) and cytomegalovirus (CMV), two of the most prevalent human herpesviruses, cause a wide spectrum of diseases and symptoms and are associated with serious health problem. In this study, we developed an internal control reference recombinase-aided amplification (ICR-RAA) assay for the rapid detection of EBV and CMV within 30 min. The assay had a sensitivity of 5 and 1 copies/test for EBV and CMV, respectively, with no cross reaction with other pathogens. In comparison with those of the commercial quantitative polymerase chain reaction (qPCR), the sensitivity of the EBV and CMV ICR-RAAs using extracted DNA was 93.33% and 84.84%, respectively; the specificity was 98.75% and 100.00%, respectively; and the Kappa values were 0.930 and 0.892 ( P < 0.05), respectively. In comparison with those of qPCR, the sensitivity of the EBV and CMV ICR-RAAs using the DNA by thermal lysis was 72.22% and 80.00%, respectively; the specificity was 100.00%; and the Kappa values were 0.764 and 0.878 ( P < 0. 05), respectively. Thus, rapid and specific detection of EBV and CMV is possible using ICR-RAA assays.

SH2 domain-containing protein tyrosine phosphatase-2 (SHP-2) prevents cardiac remodeling after myocardial infarction through ERK/SMAD signaling pathway.

In this study, we aimed to investigate the role of SH2 domain-containing protein tyrosine phosphatase-2 (SHP-2) in cardiac remodeling after myocardial infarction (MI) and explore the underlying molecular mechanism. MI model was established by ligation of the left anterior descending coronary artery. C57/BL6J mice were randomly administered with 3.0 mg/kg/day PHPS1 (PHPS1-treated group) or normal saline (model group) by intraperitoneal injection. After 4 weeks of infusion, the effects of PHPS1 on cardiac remodeling were evaluated. Echocardiography results showed that PHPS1 treatment aggravated the MI-induced deterioration of cardiac function, with worse cardiac function parameters. PHPS1 treatment significantly increased the infarcted area, as well as the fibrotic area and the expression of collagen I and collagen III. Western blots and immunofluorescence staining showed that PHPS1 treatment up-regulated the expression of p-GRK2, p-SMAD2/3 and p-ERK1/2, while U0126 reversed the effect of PHPS1. The present study indicated that PHPS1 treatment contributed to myocardial fibrosis and infarction by activating ERK/SMAD signaling pathway, suggesting that SHP-2 may be a promising treatment target for cardiac remodeling after MI.

Specific inhibition of SHP2 suppressed abdominal aortic aneurysm formation in mice by augmenting the immunosuppressive function of MDSCs.

AIMS: To address the roles of SHP2 in regulating angiotensin II (Ang II) induced abdominal aortic aneurysm (AAA) and the potential molecular mechanisms. MAIN METHODS: AAA model was established in apolipoprotein E-deficient (apoE-/-) mice infused with Ang II. Suprarenal aortic luminal diameters were ultrasonically measured to determine the presentation of AAA in mice. The inflammatory and immunosuppressive factors in serum were detected by ELISA. AAA lesion size, positive macrophages and elastic laminae degradation were examined by histological analysis. Myeloid-derived suppressor cells (MDSCs) were measured by flow cytometry after magnetic bead sorting. Bioinformatics analysis was applied to screen the crucial genes related the progression of AAA. KEY FINDINGS: Treatment with PHPS1 (SHP2 inhibitor) significantly decreased the vascular diameter of AAA. Histological analysis showed that PHPS1 obviously reduced the Masson positive area, macrophages positive area, as well as the damage rate of elastic laminae. Moreover, PHPS1 suppressed the expression of INF-γ, TNF-α and MMPs, as well as elevated IL-10 and arginase-1 expression. Additionally, PHPS1 enhanced the expression of granulocytic MDSCs (G-MDSCs). By consulting with bioinformatics, STAT3 was selected. In G-MDSCs, PHPS1 stimulation obviously increased the phosphorylation level of STAT3, as well as elevated the protein expression of C/EBPß and arginase-1. However, the above phenomena can be blocked after Stattic (STAT3 inhibitor) treatment. SIGNIFICANCE: SHP2 may affect the AAA progression by interfering with expansion and function of MDSCs to regulate the body immunity, which might afford a novel direction for the treatment of patients with AAA.

Efficient lattice Boltzmann method for electrohydrodynamic solid-liquid phase change.

Melting in the presence of electrohydrodynamic (EHD) flow driven by the Coulomb force in dielectric phase change material is numerically studied. A model is developed for the EHD flow in the solid-liquid phase change process. The fully coupled equations including mechanical equations, electrical equations, energy equations, and the continuity equations in the solid-liquid interface are solved using a unified lattice Boltzmann model (LBM). Firstly, the numerical model is validated by several cases in the hydrostatic state, and all LBM results are found to be highly consistent with analytical solutions. Besides, our LBM code is able to reproduce the step changes in the distribution of charge density and electric field due to the discontinuous distribution of physical properties at the interface. Then, a systematical investigation is conducted on various nondimensional parameters, including electric Rayleigh number T, Prandtl number Pr, and Stefan number St. Results are presented for the transient evolutions of temperature, fluid flow, charge density fields, and liquid fraction. Four flow stages in the melting process together with three kinds of flow instabilities are observed. It is found that the electric field has significant influence on the melting, especially at high T and Pr and low St. Over the tested cases, a maximum melting time saving of around 50% is found.

Establishment of validated models for non-invasive prediction of rectal temperature of sows using infrared thermography and chemometrics.

Rectal temperature is an important physiological indicator used to characterize the reproductive and health status of sows. Infrared thermography, a surface temperature measurement technology, was investigated in this study to explore its feasibility in non-invasive detection of rectal temperature in sows. A total of 124 records of rectal temperature and surface temperature in various body regions of 99 Landrace × Yorkshire crossbred sows were collected. These surface temperatures together with ambient temperature, ambient humidity, and wind speed in pig pens were correlated with the real rectal temperature of sows to establish rectal temperature prediction models by introducing chemometrics algorithms. Two types of models, i.e., full feature models and selected feature models, were established by applying the partial least squares regression (PLSR) method. The optimal model was attained when 7 important features were selected by LARS-Lasso, where correlation coefficients and root mean squared errors of calibration were 0.80 and 0.30 °C, respectively. Particularly, the validity and stability of established simplified models were further evaluated by applying the model to an independent prediction set, where correlation coefficients and root mean squared errors for prediction were 0.80 and 0.35 °C, respectively. The validation of established models is scarce in previous similar studies. Above all, this study demonstrated that introduction of chemometrics methodologies would lead to more reliable and accurate model for predicting sow rectal temperature, thus the potential for ensuring animal welfare in a broader view if extended to more applications.

Simple and fast approach to exploit the spectral reflection properties of liquid media.

Bidirectional reflectance distribution functions (BRDFs) are of importance for their wide applications. In this study, we presented a simple and fast approach to measure the spectral BRDF of both solid and liquid samples. Based on this approach, we fabricated a prototype and measured the BRDF value of some liquid samples such as water and NaCl solution at different wavelengths. According to the experimental data, we discussed the trend of the BRDF value of the NaCl solution of different concentrations. Then, the experimental data of the different NaCl solution at 637 nm were used to invert the parameters of a five-parameter model. Additionally, we fitted the parameters as a polynomial.

Multiscale solutions of radiative heat transfer by the discrete unified gas kinetic scheme.

The radiative transfer equation (RTE) has two asymptotic regimes characterized by the optical thickness, namely, optically thin and optically thick regimes. In the optically thin regime, a ballistic or kinetic transport is dominant. In the optically thick regime, energy transport is totally dominated by multiple collisions between photons; that is, the photons propagate by means of diffusion. To obtain convergent solutions to the RTE, conventional numerical schemes have a strong dependence on the number of spatial grids, which leads to a serious computational inefficiency in the regime where the diffusion is predominant. In this work, a discrete unified gas kinetic scheme (DUGKS) is developed to predict radiative heat transfer in participating media. Numerical performances of the DUGKS are compared in detail with conventional methods through three cases including one-dimensional transient radiative heat transfer, two-dimensional steady radiative heat transfer, and three-dimensional multiscale radiative heat transfer. Due to the asymptotic preserving property, the present method with relatively coarse grids gives accurate and reliable numerical solutions for large, small, and in-between values of optical thickness, and, especially in the optically thick regime, the DUGKS demonstrates a pronounced computational efficiency advantage over the conventional numerical models. In addition, the DUGKS has a promising potential in the study of multiscale radiative heat transfer inside the participating medium with a transition from optically thin to optically thick regimes.

[Bioinformation analysis of chorismate synthase in Baphicacantus cusia and other 78 species of plants].

Chorismate synthase(CS, EC:4.2.3.5) catalyses 5-enolpyruvy-shikimate-3-phosphate to form chorismate, which is the essential enzyme for chorismate biosynthesis in organisms. The amino acid sequences of CS from 79 species of higher plants were reported in GenBank at present. 125 amino acid sequences of CS from Baphicacanthus cusia and other 78 species of plants were predicted and analyzed by using various bioinformatics software, including the composition of amino acid sequences, signal peptide, leader peptide, hydrophobic/hydrophilic, transmembrane structure, coiled-coil domain, protein secondary structure, tertiary structure and functional domains. The phylogenetic tree of CS protein family was constructed and divided into eight groups by phylogenetic analysis. The homology comparison indicated that B. cusia shared a high homology with several plants such as Sesamum indicum, Nicotiana tabacum, Solanum tuberosum and so on. The open reading frame(ORF) of all samples is about 1 300 bp, the molecular weight is about 50 kDa, the isoelectric point(pI) is 5.0-8.0 which illustrated that CS protein is slightly basic. The ORF of CS we cloned in B. cusia is 1 326 bp, the amino acid residues are 442, the molecular weight is 47 kDa and pI is 8.11. The CS in B.cusia showed obvious hydrophobicity area and hydrophilicity area, no signal peptide, and may exists transmembrane structure areas. The main secondary structures of CS protein are random coil and Alpha helix, also contain three main structural domains which are an active structural domain, a PLN02754 conserved domain and a FMN binding site. The acquired information in this study would provide certain scientific basis for further study on structure-activity relationship and structure modification of CS in plants in the future.

Responses transition in a monolayer Al-Al2O3 nanoparticle-crystal due to oxidation.

Nanoparticle is a promising candidate for large scale fabrication of metamaterial. However, optical responses for metamaterial made of abound metal like Al can be thoroughly changed due to oxidization. Especially for nanoparticle whose aspect ratio is extremely high, oxidation usually occurs. So to understand how the responses shift in a nanoparticle system due to oxidization is essential for large scale application of metamaterial. In this paper, we have concluded and quantified two general principles describing this transition in a monolayer Al-Al2O3 nanoparticle-crystal, which can be used in a thermophotovoltaic system. Square pattern, in which the unit of changing crystal is a square cell made up of Al and Al2O3 particles, is firstly demonstrated. A double oscillators model has been proposed to understand the interference between different absorption modes and their coupling. Using near-field distribution, equivalent inductor-capacitor model and dispersion relationship of surface Plasmon polariton, we have distinguished the resonance modes, concluded the transition principles in a simple case. Then the two principles are applied in a larger cell to verify its university. After detailed demonstration of symmetric square pattern, models and principles are extrapolated to more complex non-symmetric systems. The basic understanding gained here will help the design of robust large-scale metamaterial.

[Molecular mechanism of artemisinin biosynthesis and regulation in Artemisia annua].

Artemisinin-based combination therapy (ACT) is the best available treatment, particularly for Plasmodium falciparum malaria. Artemisinin, whose main source is Artemisia annua, has large demand and shortsupply every year.Artemisininis synthesized,stored, and secreted by the glandular secretory trichomes of A. annua(AaGSTs).In general, the population and morphology of AaGSTs are often positively correlated with artemisinin content.This review article introduces the molecular mechanism of biosynthesis and regulation of artemisininin A. annua. Furthermore, this article will refresh the classification of trichomes in A. annua and provide anoverview of the recent achievements regarding AaGSTs and artemisinin.These will shed light on exploring the method for increasing plant-derived artemisinin.

Transient/time-dependent radiative transfer in a two-dimensional scattering medium considering the polarization effect.

Transient/time-dependent radiative transfer in a two-dimensional scattering medium is numerically solved by the discontinuous finite element method (DFEM). The time-dependent term of the transient vector radiative transfer equation is discretized by the second-order central difference scheme and the space domain is discretized into non-overlapping quadrilateral elements by using the discontinuous finite element approach. The accuracy of the transient DFEM model for the radiative transfer equation considering the polarization effect is verified by comparing the time-resolved Stokes vector component distributions against the steady solutions for a polarized radiative transfer problem in a two-dimensional rectangular enclosure filled with a scattering medium. The transient polarized radiative transfer problems in a scattering medium exposed to an external beam and in an irregular emitting medium are solved. The distributions of the time-resolved Stokes vector components are presented and discussed.

Nanoparticle-crystal towards an absorbing meta-coating.

In this paper, a double layer nanoparticle-crystal has been proposed, which shown incident and polarization angle, substrate independences for spectral absorptivity. Such phenomenon originates from the near-field light redistribution and excitation of internal collective oscillating. This kind of nanoparticle-crystal can be made of various types of metal with similar optical responses. A three oscillators mode has been proposed in this paper to understand the shift between global and internal collective oscillating, and verify the physical picture demonstrated. That kind of near-field redistribution result in a prototype of novel meta-coating, and facilitates the large scale application of metamaterial.