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Background: Sheep are an important livestock species worldwide and an essential large-animal model for animal husbandry and veterinary research. Understanding fundamental immune indicators, especially T-lymphocyte parameters, is necessary for research on sheep diseases and vaccines, to better understand the immune response to bacteria and viruses for reducing the use of antibiotics and improving the welfare of sheep. We randomly selected 36 sheep of similar ages to analyze cell-related immune indicators in peripheral blood mononuclear cells (PBMCs). The proportions of CD4+ and CD8+ T cells in PBMCs were detected by flow cytometry. We used Concanavalin A (Con A) and Phorbol-12-myristate-13-acetate (PMA)/Ionomycin to stimulate PBMCs, and measured the expression of IFN-γ, IL-4, and IL-17A using enzyme-linked immunosorbent assay (ELISA) and enzyme-linked immunospot assay (ELISpot). Simultaneously, PMA/Ionomycin/brefeldin A (BFA) was added to PBMCs, then the expression of IFN-γ, IL-4, and IL-17A was detected by flow cytometry after 4 h of culturing. In addition, we observed the proliferation of PBMCs stimulated with Con A for 3, 4, and 5 days. Results: The proportions of CD4+ T lymphocytes (18.70 ± 4.21%) and CD8+ T lymphocytes (8.70 ± 3.65%) were generally consistent among individuals, with a CD4/CD8 ratio of 2.40 ± 0.79. PBMCs produced high levels of IFN-γ, IL-4, and IL-17A after stimulation with PMA/Ionomycin and Con A. Furthermore, PMA/Ionomycin stimulation of PBMC yielded significantly higher cytokine levels than Con A stimulation. Flow cytometry showed that the level of IFN-γ (51.49 ± 11.54%) in CD8+ T lymphocytes was significantly (p < 0.001) higher than that in CD4+ T lymphocytes (14.29 ± 3.26%); IL-4 (16.13 ± 6.81%) in CD4+ T lymphocytes was significantly (p < 0.001) higher than that in CD8+ T lymphocytes (1.84 ± 1.33%), There was no difference in IL-17A between CD4+ (2.83 ± 0.98%) and CD8+ T lymphocytes (1.34 ± 0.67%). The proliferation of total lymphocytes, CD4+ T lymphocytes, and CD8+ T lymphocytes continued to increase between days 3 and 5; however, there were no significant differences in proliferation between the cell types during the stimulation period. Conclusions: Evaluating primary sheep immune indicators, especially T lymphocytes, is significant for studying cellular immunity. This study provided valuable data and theoretical support for assessing the immune response of sheep to pathogens and improving sheep welfare. [ABSTRACT FROM AUTHOR]

Large scale fiber bridging in composite laminates is one of the most common toughening mechnisms, exerting a close-force on the crack surfaces to restrain the delamination propagation. To account for the effect of the fiber bridging in delamination simulation, a physically semi-analytical method based on the Euler-Bernoulli beam theory considering the bridging stress is presented. The mode I energy release rate for every crack length is explicitly expressed in terms of the external load and bridging-traction parameters, which are iterately identified by the proposed optimization procedure. Based on the presented method, a cohesive zone model integrating the identified bridging-tractions is established to simulate the mode I delamination of three kinds of composite laminates with different interfaces, the numerical results correspond well with the experimental ones, indicating the effectiveness and applicability of the presented method. The delamination morphologies are investigated for better interpretation of the toughening mechanism. The major advantage of the proposed method is that it is efficient and convienient since only basic material properties and experimental load–displacement data of the double cantilever beam specimens are required, without additional parameters measurement with the help of external equipments. [ABSTRACT FROM AUTHOR]

Traditional von Neumann architecture, characterized by separate memory and processing units connected by a limited-capacity memory bus, faces challenges in handling tasks with high energy efficiency requirements. In contrast, the compute-in-memory (CIM) architecture offers a promising alternative, facilitating high parallelism in data processing while integrating storage functions, thereby significantly reducing memory access frequency and power consumption. This study presents a fully digital CIM macro featuring a novel self-write-back 12T cell. This bitcell is capable of performing Boolean logic operations and autonomously writing back results into the in-situ cell, thereby significantly improving energy efficiency.This can be used for binary logical operations between each pixel of two images without requiring additional storage area. A bidirectional read/write architectural design enables matrix transposition. This can achieve image rotation.Additionally, this novel 12T cell also offers the option to choose not to write back the results of logical operations, thereby providing the flexibility and configurability for image processing. Combined with an adder tree, it enables multiply-and-accumulate (MAC) operation for convolutional neural networks(CNNs). This can be used for feature extraction. We propose an 18T full adder structure with lower power-delay product than current state-of-the-art full adders, which is advantageous for improving the synthesis performance of the adder tree.The CIM macro supports a 4-bit × 4-bit MAC operation. The proposed CIM macro, designed and simulated using a 28 nm CMOS process with a 16 Kb static random access memory (SRAM), demonstrates promising results. At VDD = 0.9 V, the logic operation energy consumption is 1.35 fJ/bit with an energy efficiency of 740TOPS/W, and MAC operation energy consumption is 15.91 fJ/bit with an energy efficiency of 62.85 TOPS/W. [ABSTRACT FROM AUTHOR]

Large-scale fiber bridging developed in the CRFP multidirectional (MD) laminates upon mixed-mode I/II fracture has a significant effect on the delamination behavior. Without considering the effect of fiber bridging, traditional delamination propagation criteria fail to evaluate the delamination behavior in MD laminates. To solve this problem, an improved criterion is proposed here, which accounts for the delamination resistance curve ( R -curve) induced by fiber bridging. Systematic delamination tests under mode I, II and mixed I/II loadings were carried out to determine the unique parameter in the criterion and a numerical delamination model based on the cohesive zone model (CZM) was established with implementation of the improved criterion. Initial and ultimate damage loads from numerical predictions and experiments show good agreements, verifying the accuracy of the improved criterion on evaluating the mixed-mode I/II delamination behavior in MD laminates. Additional mixed-mode I/II delamination test was conducted, which was used to validate the applicability of the improved criterion on evaluating the delamination behavior with any other mode-mixity ratios ( φ -ratios). [ABSTRACT FROM AUTHOR]

The Sb 2 O 5 modified SnO 2 porous nanocomposites serving as NO 2 gas sensing material have been successfully synthesized through a facile hydrothermal method followed by a calcination process. The porous Sb 2 O 5 /SnO 2 nanocomposites display a dominant pore size of ca. 20 nm and specific surface area of 37.2 m 2 g −1 , which can provide large contact area for the chemical adsorption of NO 2 molecules and abundant channels for the import and export of NO 2 gas. Gas sensing tests demonstrated that the as-prepared porous Sb 2 O 5 /SnO 2 nanocomposites (1 mol% Sb 2 O 5 ) achieved superior sensing performances including high selectivity to NO 2 , low optimal operating temperature (ca. 100 °C), high response (800–5 ppm NO 2 ), and short response and recovery times (20 s and 70 s to 5 ppm NO 2 , respectively). Comparing with pure SnO 2 porous structure, the enhanced gas sensing performances of the porous Sb 2 O 5 /SnO 2 nanocomposites are mainly ascribed to the p - n junctions generated from the hybrid of n-type SnO 2 with p-type Sb 2 O 5 , which not only improved the response and selectivity to NO 2 gas, but also reduced the operating temperature. [ABSTRACT FROM AUTHOR]

Although both are myeloid cells located surrounding cerebral vasculature, vessel-associated microglia (VAM) and perivascular macrophages (PVMs) can be distinguished by their distinct morphologies, signatures and microscopic location. As key component of neuro-glia-vascular unit (NGVU), they play prominent roles in neurovasculature development and pathological process of various central nervous system (CNS) diseases, including phagocytosis, angiogenesis, vessel damage/protection and blood flow regulation, therefore serving as potential targets for therapeutics of a broad array of CNS diseases. Herein, we will provide a comprehensive overview of heterogeneity of VAM/PVMs, highlight limitations of current understanding in this field, and discuss possible directions of future investigations. • VAM and PVMs show different origins and distinct contrasts in morphologies, signatures and locations. • VAM and PVMs respectively play crucial roles in vasculature maintanence and pathological progression. • Spatial techniques are expected to advance our knowledge of the intrinsic nature and multifaceted functions of VAM/PVMs. [ABSTRACT FROM AUTHOR]

Two Paris-type models are proposed to characterize the fatigue delamination growth (FDG) behavior in CFRP laminates. The crack-driving forces denoted by two definitions of the strain energy release rate (SERR) range against the fatigue delamination resistance of composite materials are introduced to control the FDG. The first definition is the square of the difference between the square root of maximum SERR and that of minimum SERR. The second one is the arithmetic difference between the maximum and minimum SERR. A series of fatigue delamination tests of CFRP multidirectional laminates under various stress ratios and mode-mixity ratios were carried out. Among different Paris relations, the FDG rate corrected by the first model exhibits a linear relationship with R -ratio dependency, and the second model further removes the R -ratio dependence, under different mode-mixity ratios, on a log-log scale. The experimental results indicate that the presented models can provide more generic descriptions and a proper interpretation of the FDG behavior in CFRP multidirectional laminates. [ABSTRACT FROM AUTHOR]

The hydrodynamic behaviors of a vertical round jet in regular and random waves are comparatively investigated. The regular and the random waves are chosen based on the concept of equivalent energy density and energy flux. The experimental study is first carried out to compare the lateral profiles of jet mean axial velocity at various vertical levels. The results show that, under the present experimental conditions, the phenomenon of “twin peaks” appears in the regular waves, but virtually does not exist in the corresponding random waves. This results in a lower axial velocity along the centerline for the jet in the regular waves. A large eddy simulation (LES) model is subsequently developed to quantify the difference of jet half-width under the same wave conditions as those in the laboratory. The numerical results show that the jet in the random waves has a larger jet half-width than that in the regular waves, which is consistent with the visual observations in laboratory experiments. More scenarios of the jet in different regular and random waves are numerically investigated and the results show that the “twin peaks” may also appear under the condition of random waves, but requiring a larger wave-to-jet momentum ratio. [ABSTRACT FROM AUTHOR]

Abstract: Synthesis of Y3Al5O12 (YAG) powders respectively presents morphology control and chemical stoichiometry problems when employing the solid-state reaction or the wet-chemical route. YAG powder retaining the morphology of Al2O3 powder was designed and synthesized via a partial wet-chemical process with yttrium ions precipitating on the Al2O3 particles. The formation process of the Y-compound/Al2O3 core–shell structure is discussed on the basis of zeta-potential measurements and HRTEM results. Two stages, including direct precipitation at the surface of the Al2O3 particles and the assembly of the yttrium precipitate from explosive nucleation onto the yttrium compound-coated Al2O3 particles, are proposed. A spherical surface reaction process is illustrated. A pure YAG phase can be realized at a temperature about 300°C lower than that of the traditional solid-state reaction process. [Copyright &y& Elsevier]

The objective of this paper is mainly to investigate the ventilated cavitating flow characteristics around an axisymmetric body with a focus on three-dimensional unsteady behaviors. A high-speed camera technique is used to record the ventilated cavitating flow patterns. A homogeneous free surface model coupled with Filter-based turbulence model is used to simulate the time-evolution process of the unsteady cavitating flows. Numerical results show a reasonable agreement with the experimental data. The evolution of the ventilated cavity quasi-periodic unsteady shedding is well captured and discussed. The asymmetric and three-dimensional unsteady behaviors are impressive in the ventilated cavitating flow. Further analysis demonstrates that the re-entrant jet which originates from different circumferential positions at the closure region of the cavity moves upstream with different speeds. Lagrangian coherent structures (LCS) methods are applied to reveal the influence of re-entrant jet on the U-type cavity shedding and it shows that there is a close relationship between unsteady behaviors and the re-entrant jet flow motion consisting of moving upstream and circumferential. In addition, the effect of asymmetry on unsteady shedding behaviors of ventilated cavitating flow at different angles of attack have also been investigated combined with LCS methods. • The ventilated cavitating flow characteristics around an axisymmetric body with focus on the three-dimensional unsteady behaviors is investigated. • Lagrangian coherent structures (LCS) methods are applied to reveal the influence of re-entrant jet on the U-type cavity shedding. • The typical ventilated cavitating flow structures at different angles of attack have been studied. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) often leads to enduring axonal damage and persistent neurological deficits. While PTEN's role in neuronal growth is recognized, its long-term activation changes post-TBI and its effects on sensory-motor circuits are not well understood. Here, it is demonstrated that the neuronal knockout of PTEN (PTEN-nKO) significantly enhances both structural and functional recovery over the long term after TBI. Importantly, in vivo, DTI-MRI revealed that PTEN-nKO promotes white matter repair post-TBI. Additionally, calcium imaging and electromyographic recordings indicated that PTEN-nKO facilitates cortical remapping and restores sensory-motor pathways. Mechanistically, PTEN negatively regulates the Akt/mTOR pathway by inhibiting Akt, thereby suppressing mTOR. Raptor is a key component of mTORC1 and its suppression impedes axonal regeneration. The restoration of white matter integrity and the improvements in neural function observed in PTEN-nKO TBI-treated mice are reversed by a PTEN/Raptor double knockout (PTEN/Raptor D-nKO), suggesting that mTORC1 acts as a key mediator. These findings highlight persistent alterations in the PTEN/Akt/mTORC1 axis are critical for neural circuit remodeling and cortical remapping post-TBI, offering new insights into TBI pathophysiology and potential therapeutic targets., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Organophosphate esters (OPEs) are widespread in the environment, with high persistence and toxicity. However, the underlying mechanisms of anaerobic microbial degradation of OPEs remain elusive in the field environment. In this study, the natural attenuation mechanisms of tributyl phosphate (TnBP) by indigenous anaerobic microorganisms in soils were investigated by using compound-specific stable isotope analysis (CSIA) and characterization of microbial communities. The results indicated that dibutyl phosphate (DnBP) was the major degradation product of TnBP. Significant carbon isotope fractionation was observed for TnBP during the anaerobic microbial degradation, and the carbon isotope enrichment factor (ε C ) was determined to be -2.71 ± 0.13‰. Unlike aerobic degradation with P-O bond cleavage, C-O bond cleavage was verified as the mode to removal a butyl side chain for TnBP to generate DnBP during the anaerobic microbial degradation. Microbial community analysis indicated that Sphingomonans, Nocardioides and Streptomyces were the important contributors to microbial degradation of TnBP in anoxic soils. TnBP altered microbial metabolic functions in anoxic soils, mainly enhancing the biosynthesis of ansamycins, ketone bodies and amino acids, and flagellar assembly, which promoted microbial degradation of TnBP. This study provided a better method to characterize the chemical bond cleavage mode and effect of OPEs on microbial communities, which was a prerequisite for the bioremediation of OPE pollution in soils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Despite the wide use of compression garments to enhance athletic running performance, evidence supporting improvements has not been conclusive. This updated systematic review and meta-analysis of randomized controlled trials (RCTs) compared the effects of compression garment wearing with those of non-compression garment wearing (controls) during running on improving running performance., Methods: A comprehensive search was conducted in the electronic databases (Web of Science, EBSCOhost, PubMed, Embase, Scopus, and Cochrane) for RCTs comparing running performance between runners wearing compression garments and controls during running, from inception to September 2024. Independent reviewers screened studies, extracted data, appraised risk of bias (RoB 2) and certainty of evidence (Grading of Recommendations Assessments, Development and Evaluation, GRADE). Primary outcomes were race time and time to exhaustion. Secondary outcomes covered running speed and race pace, submaximal oxygen uptake, tissue oxygenation, and soft tissue vibration. Random-effects meta-analyses were conducted to generate pooled estimates, expressed in standardized mean difference (SMD). Subgroup differences of garment, race type, and contact surface were tested in moderator analyses., Results: The search yielded 51 eligible studies comprising 899 participants, of which 33 studies were available for meta-analysis of primary outcomes. Runners wearing compression garments during running showed no significant improvement in race time (SMD = -0.07, 95 % CI: -0.22 to 0.09; p = 0.40) or time to exhaustion (SMD = 0.04, 95 % CI: -0.20 to 0.29; p = 0.72). Moderator analyses indicated no effects from garment type, race type, or surface. Secondary outcomes also showed no performance benefits, although compression garments significantly reduced soft tissue vibration (SMD = -0.43, 95 % CI: -0.70 to -0.15; p < 0.01). Certainty of evidence was rated low to very low., Conclusion: Data synthesis of current RCTs offers no updated evidence favoring the support of wearing compression garments during running as a viable strategy for improving running and endurance performance among runners of varying performance levels and types of running races., Competing Interests: Competing interests The authors declare that they have no competing interests., (Copyright © 2025. Production and hosting by Elsevier B.V.)

Rational: White matter has emerged as a key therapeutic target in ischemic stroke due to its role in sensorimotor and cognitive outcomes. Our recent findings have preliminarily revealed a potential link between microglial HDAC3 and white matter injury following stroke. However, the mechanisms by which microglial HDAC3 mediates these effects remain unclear. Methods : We generated microglia-specific HDAC3 knockout mice (HDAC3-miKO). DTI, electrophysiological technique and transmission electron microscopy were used to assess HDAC3-miKO's effects on white matter. RNA sequencing, flow cytometry, immunofluorescence staining and ex vivo phagocytosis assay were conducted to investigate the mechanism by which HDAC3-miKO ameliorated white matter injury. Macrophage depletion and reconstitution experiments further confirmed the involvement of macrophage CCR2 in the enhanced white matter repair and sensorimotor function in HDAC3-miKO mice. Results : HDAC3-miKO promoted post-stroke oligodendrogenesis and long-term histological and functional integrity of white matter without affecting early-stage white matter integrity. In the acute phase, HDAC3-deficient microglia showed enhanced chemotaxis, recruiting macrophages to the infarct core probably by CCL2/CCL7, where dMBP-labelled myelin debris surged and coincided with their infiltration. Infiltrated macrophages outperformed resident microglia in myelin phagocytosis, potentially serving as true pioneers in myelin debris clearance. Although macrophage phagocytosis potential was similar between HDAC3-miKO and WT mice, increased macrophage numbers in HDAC3-miKO accelerated myelin debris clearance. Reconstitution with CCR2-KO macrophages in HDAC3-miKO mice slowed this clearance, reversing HDAC3-miKO's beneficial effects. Conclusions : Our study demonstrates that HDAC3-deficient microglia promote post-stroke remyelination by recruiting macrophages to accelerate myelin debris clearance, underscoring the essential role of infiltrated macrophages in HDAC3-miKO-induced beneficial outcomes. These findings advance our understanding of microglial HDAC3's role and suggest therapeutic potential for targeting microglial HDAC3 in ischemic stroke., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Uptake, translocation, and transformation mechanisms of tris(2-chloroethyl) phosphate (TCEP) in hydroponic wheat ( Triticum aestivum L.) were systematically investigated using compound-specific stable isotope and multiomics analyses in this study. Results showed that TCEP was quickly adsorbed on root epidermis and then absorbed in roots via water and anion channels as well as an active process dependent on energy. Active process and anion channel preferentially translocated TCEP-containing light carbon isotopes and dominated the transmembrane transport of TCEP to enter vascular bundle. Transcriptomic and metabolomic analyses indicated gene-encoding ATP-binding cassette (ABC) transporters and purple acid phosphatases (PAPs) and glutathione S-transferases (GSTs) involved in TCEP transport and transformation, respectively. Molecular docking simulations showed that TCEP bound to the hydrophilic cavity of ABC transporter/PAP and hydrophobic cavity of GST, and hydrogen bonding was the important driving force. The results of this study offered insights for future effective mitigation of TCEP risk in edible plants.

Spodoptera litura (S. litura) is a polyphagous pest of the family Lepidoptera, which causes damage and yields losses to many crops. The long-term use of chemical pesticides for control not only seriously threatens environmental health, but also causes S. litura to develop drug resistance. Therefore, there is an urgent need to develop environmentally safe and friendly biogenic pesticides. However, the mechanism of action of the secondary metabolite (surfactin) of Bacillus Vélezensis (B. vélezensis) on lepidopteran pests (S. litura) has not been reported yet. We found that several metabolites and genes in S. litura were affected by surfactin exposure. The expressions of the metabolites (protoporphyrinogen (PPO), gluconolactone (GDL), and L-cysteate) were significantly down-regulated while glutamate and hydroxychloroquine were significantly up-regulated. The expression levels of genes related to drug metabolism and detoxification, include the glutathione s-transferase (GST) gene family and acetaldehyde dehydrogenase (ALDH), and apoptosis-inhibiting genes (seven in absentia homolog 1(SIAH1)) were significantly decreased. In addition, pathological changes occurred in intestinal wall cells, Malpighian tubule cells, and nerve cells of S. litura under surfactin stress. Conclusively, our results suggest that surfactin induces an increase in reactive oxygen species (ROS) and damages S. litura cells. Furthermore, based on the integrated analysis of transcriptomic and metabolomic data, it is hypothesized that surfactin may also trigger neurotoxicity and cardiotoxicity in S. litura while hindering the insect's detoxification processes. This study lays a foundation for further exploration of surfactin as a potential biopesticide., Competing Interests: Declarations. Competing interests: The following authors, F.Y.Z, Q.Y.L, Y.N.W, J.L.W, W.Y.Z, H.W.L and L.P.Z declare competing financial interests. J.L.Y and X.H.M declare no conflict of interest. There are three patents related to this article. They are ZL20221055584.3, ZL 202210554798.9, ZL 202210555620.6. A patent CHINA 20221055584.3 was issued on 2/2023 and describes a B. vélezensis ZLP-101 and its application in insecticides. A patent CHINA 202210554798.9 was issued on 4/2023 and describes the application of the metabolite of B. vélezensis ZLP-101 in the development of insecticidal and disease-control composite microbial agents and bio-fertilizers. A patent CHINA 202210555620.6 was issued on 2/2023 and describes the development of metabolites from B. vélezensis ZLP-101 into a composite bacterial agent and an insecticidal seed coating agent., (© 2024. The Author(s).)

Aims: Traumatic brain injury (TBI) stands as a significant concern in public health, frequently leading to enduring neurological deficits. Long non-coding RNA H19 (lncRNA H19) exerts a potential regulator role in the pathology of brain injury. This study investigates the effects of lncRNA H19 knockdown (H19-KD) on the pathophysiology of TBI and its potential neuroprotective mechanisms., Methods: Controlled cortical impact was employed to establish a stable TBI mouse model. The expression levels of various genes in perilesional cortex and striatum tissue after TBI was detected by RT-qPCR. AAV9-shRNA-H19 was injected into the lateral ventricle of mice to knockdown the expression of lncRNA H19. Various behavioral tests were performed to evaluate sensorimotor and cognitive functions after TBI. Immunofluorescence and Nissl staining were performed to assess brain tissue damage and neuroinflammation. The Nrf2 and HO-1 expression was performed by Western blot., Results: After TBI, the expression of lncRNA H19 was elevated in perilesional tissue and gradually reverted to baseline. Behavioral tests demonstrated that H19-KD significantly promoted the recovery of sensorimotor and cognitive functions after TBI. Besides, H19-KD reduced brain tissue loss, preserved neuronal integrity, and ameliorated white matter damage at the histological level. In addition, H19-KD restrained the pro-inflammatory and facilitated anti-inflammatory phenotypes of microglia/macrophages, attenuating the neuroinflammatory response after TBI. Furthermore, H19-KD promoted activation of the Nrf2/HO-1 axis after TBI, while suppression of Nrf2 partially abolished the neuroprotective effect., Conclusion: H19-KD exerts neuroprotective effects after TBI in mice, partially mediated by the activation of the Nrf2/HO-1 axis., (© 2024 The Author(s). CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.)

Background: Natural products are important sources for the discovery of new biopesticides to control the worldwide destructive pests Acyrthosiphon pisum Harris. Here, insecticidal substances were discovered and characterized from the secondary metabolites of the bio-control microorganism Bacillus velezensis strain ZLP-101, as informed by whole-genome sequencing and analysis., Results: The genome was annotated, revealing the presence of four potentially novel gene clusters and eight known secondary metabolite synthetic gene clusters. Crude extracts, prepared through ammonium sulfate precipitation, were used to evaluate the effects of strain ZLP-101 on Acyrthosiphon pisum Harris aphid pests via exposure experiments. The half lethal concentration (LC50) of the crude extract from strain ZLP-101 against aphids was 411.535 mg/L. Preliminary exploration of the insecticidal mechanism revealed that the crude extract affected aphids to a greater extent through gastric poisoning than through contact. Further, the extracts affected enzymatic activities, causing holes to form in internal organs along with deformation, such that normal physiological activities could not be maintained, eventually leading to death. Isolation and purification of extracellular secondary metabolites were conducted in combination with mass spectrometry analysis to further identify the insecticidal components of the crude extracts. A total of 15 insecticidal active compounds were identified including iturins, fengycins, surfactins, and spergualins. Further insecticidal experimentation revealed that surfactin, iturin, and fengycin all exhibited certain aphidicidal activities, and the three exerted synergistic lethal effects., Conclusions: This study improved the available genomic resources for B. velezensis and serves as a foundation for comprehensive studies of the insecticidal mechanism by Bacillus velezensis ZLP-101 in addition to the active components within biological control strains., (© 2024. The Author(s).)

The Class-I histone deacetylases (HDACs) mediate microglial inflammation and neurological dysfunction after traumatic brain injury (TBI). However, whether the individual Class-I HDACs play an indispensable role in TBI pathogenesis remains elusive. HDAC2 has been shown to upregulate pro-inflammatory genes in myeloid cells under brain injuries such as intracerebral hemorrhage, thereby worsening outcomes. Thus, we hypothesized that HDAC2 drives microglia toward a pro-inflammatory neurotoxic phenotype in a murine model of controlled cortical impact (CCI). Our results revealed that HDAC2 expression was highly induced in CD16/CD32 + pro-inflammatory microglia 3 and 7d after TBI. Surprisingly, microglia-targeted HDAC2 knockout (HDAC2 miKO) mice failed to demonstrate a beneficial phenotype after CCI/TBI compared to their wild-type (WT) littermates. HDAC2 miKO mice exhibited comparable levels of grey and white matter injury, efferocytosis, and sensorimotor and cognitive deficits after CCI/TBI as WT mice. RNA sequencing of isolated microglia 3d after CCI/TBI indicated the elevation of a panel of pro-inflammatory cytokines/chemokines in HDAC2 miKO mice over WT mice, and flow cytometry showed further elevated brain infiltration of neutrophils and B cells in HDAC2 miKO mice. Together, this study does not support a detrimental role for HDAC2 in microglial responses after TBI and calls for investigation into alternative mechanisms., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The accumulation of self-renewed polarized microglia in the penumbra is a critical neuroinflammatory process after ischemic stroke, leading to secondary demyelination and neuronal loss. Although known to regulate tumor cell proliferation and neuroinflammation, HDAC3's role in microgliosis and microglial polarization remains unclear. We demonstrated that microglial HDAC3 knockout (HDAC3-miKO) ameliorated poststroke long-term functional and histological outcomes. RNA-seq analysis revealed mitosis as the primary process affected in HDAC3-deficent microglia following stroke. Notably, HDAC3-miKO specifically inhibited proliferation of proinflammatory microglia without affecting anti-inflammatory microglia, preventing microglial transition to a proinflammatory state. Moreover, ATAC-seq showed that HDAC3-miKO induced closing of accessible regions enriched with PU.1 motifs. Overexpressing microglial PU.1 via an AAV approach reversed HDAC3-miKO-induced proliferation inhibition and protective effects on ischemic stroke, indicating PU.1 as a downstream molecule that mediates HDAC3's effects on stroke. These findings uncovered that HDAC3/PU.1 axis, which mediated differential proliferation-related reprogramming in different microglia populations, drove poststroke inflammatory state transition, and contributed to pathophysiology of ischemic stroke.

Background: Hemifacial macrosomia (HFM, OMIM 164210) is a complex and highly heterogeneous disease. FORKHEAD BOX I3 (FOXI3) is a susceptibility gene for HFM, and mice with loss of function of Foxi3 did exhibit a phenotype similar to craniofacial dysmorphism. However, the specific pathogenesis of HFM caused by FOXI3 deficiency remains unclear till now., Method: In this study, we first constructed a Foxi3 deficiency (Foxi3 -/- ) mouse model to verify the craniofacial phenotype of Foxi3 -/- mice, and then used RNAseq data for gene differential expression analysis to screen candidate pathogenic genes, and conducted gene expression verification analysis using quantitative real-time PCR., Results: By observing the phenotype of Foxi3 -/- mice, we found that craniofacial dysmorphism was present. The results of comprehensive bioinformatics analysis suggested that the craniofacial dysmorphism caused by Foxi3 deficiency may be involved in the PI3K-Akt signaling pathway. Quantitative real-time PCR results showed that the expression of PI3K-Akt signaling pathway-related gene Akt2 was significantly increased in Foxi3 -/- mice., Conclusion: The craniofacial dysmorphism caused by the deficiency of Foxi3 may be related to the expression of Akt2 and PI3K-Akt signaling pathway. This study laid a foundation for understanding the function of FOXI3 and the pathogenesis and treatment of related craniofacial dysmorphism caused by FOXI3 dysfunction., (© 2024 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals LLC.)

Citric acid gives lemons their unique flavor, which impacts their sensory traits and market value. However, the intricate process of citric acid accumulation during lemon fruit growth remains incompletely understood. Here, we achieved a chromosomal-level genome assembly for the 'Xiangshui' lemon variety, spanning 364.85 Mb across nine chromosomes. This assembly revealed 27 945 genes and 51.37% repetitive sequences, tracing the divergence from citron 2.85 million years ago. DNA methylome analysis of lemon fruits across different developmental stages revealed significant variations in DNA methylation. We observed decreased CG and CHG methylation but increased CHH methylation. Notably, the expression of RdDM pathway-related genes increased with fruit development, suggesting a connection with elevated CHH methylation, which is potentially influenced by the canonical RdDM pathway. Furthermore, we observed that elevated CHH DNA methylation within promoters significantly influenced the expression of key genes, critically contributing to vital biological processes, such as citric acid accumulation. In particular, the pivotal gene phosphoenolpyruvate carboxykinase ( ClPEPCK ), which regulates the tricarboxylic acid cycle, was strikingly upregulated during fruit development, concomitant with increased CHH methylation in its promoter region. Other essential genes associated with citric acid accumulation, such as the MYB transcription factor ( ClPH1/4/5 ) and ANTHOCYANIN 1 ( ClAN1 ), were strongly correlated with DNA methylation levels. These results strongly indicate that DNA methylation crucially orchestrates the metabolic synthesis of citric acid. In conclusion, our study revealed dynamic changes in DNA methylation during lemon fruit development, underscoring the significant role of DNA methylation in controlling the citric acid metabolic pathway., Competing Interests: The authors declare that they have no competing interests in this research., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nanjing Agricultural University.)

So far, power input has been used as the main parameter for bioreactor scale-up/-down in upstream process development and manufacturing. The rationale is that maintaining a consistent power input per unit volume should result in comparable mixing times at different scales. However, shear generated from turbulent flow may compromise the integrity of non-robust cells such as those used during the production of cell and gene therapies, which may lead to low product quality and yield. Of particular interest is the Kolmogorov length parameter that characterizes the smallest turbulent eddies in a mixture. To understand its impact on scale-up/-down decisions, the distribution of Kolmogorov length along the trajectory flow of individual particles in bioreactors was estimated in silico with the help of computational fluid dynamics simulations. Specifically, in this study the scalability of iPSC-derived lymphocyte production and the impact of shear stress across various differentiation stages were investigated. The study used bioreactors of volumes from 0.1 to 10 L, which correspond to the scales most used for parameter optimization. Our findings, which align with in vitro runs, help determine optimal agitation speed and shear stress adjustments for process transfer between scales and bioreactor types, using vertically-oriented wheel and pitched-blade impellers. In addition, empirical models specific to the bioreactors used in this study were developed. The provided computational analysis in combination with experimental data supports selection of appropriate bioreactors and operating conditions for various cell and gene therapy process steps., (© 2023 The Authors. Biotechnology Journal published by Wiley-VCH GmbH.)

Echinococcosis is a common human and animal parasitic disease that seriously endangers human health and animal husbandry. Although studies have been conducted on vaccines for echinococcosis , to date, there is no human vaccine available for use. One of the main reasons for this is the lack of in-depth research on basic immunization with vaccines. Our previous results confirmed that recombinant antigen P29 (rEg.P29) induced more than 90% immune protection in both mice and sheep, but data on its induction of sheep-associated cellular immune responses are lacking. In this study, we investigated the changes in CD4 + T cells, CD8 + T cells, and antigen-specific cytokines IFN-γ, IL-4, and IL-17A after rEg.P29 immunization using enzyme-linked immunospot assay (ELISPOT), enzyme-linked immunosorbent assay (ELISA), and flow cytometry to investigate the cellular immune response induced by rEg.P29 in sheep. It was found that rEg.P29 immunization did not affect the percentage of CD4 + and CD8 + T cells in peripheral blood mononuclear cells (PBMCs), and was able to stimulate the proliferation of CD4 + and CD8 + T cells after immunization in vitro . Importantly, the results of both ELISPOT and ELISA showed that rEg.P29 can induce the production of the specific cytokines IFN-γ and IL-17A, and flow cytometry verified that rEg.P29 can induce the expression of IFN-γ in CD4 + and CD8 + T cells and IL-17A in CD4 + T cells; however, no IL-4 expression was observed. These results indicate that rEg.P29 can induce Th1, Th17, and Tc1 cellular immune responses in sheep against echinococcosis infection, providing theoretical support for the translation of rEg.P29 vaccine applications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Yang, Zhao, Fu, Lv, Zhu, Zhu, Zhao, Wang, Wu and Zhao.)

Background: Different subtypes of dendritic cells (DCs) can induce different types of immune responses. Our previous study found that Echinococcus granulosus (E. granulosus) antigens (Eg.ferritin, Eg.mMDH and Eg.10) stimulated DC differentiation to different subtypes and produced different immune responses., Objective: To further understand whether Eg.ferritin, Eg.mMDH and Eg.10 affect the DC-mediated immune response by promoting the differentiation of monocytes to DCs., Methods: Bone marrow-derived monocytes were exposed to three antigens of E. granulosus on days 0, 3, 5, and 7. The percentage of monocyte-derived DCs (moDCs), DCs subsets, and the expression of surface molecules of DCs at different time points in different groups were assessed by flow cytometry. The levels of cytokines of IL-1β, IL-4, IL-6, IL-10, IL-13, IFN-γ, TNF-α, IL-12p70, IL-18, IL-23, and IL-27 in the cell culture supernatant were detected by multi-factorial detection technology., Results: The percentage of moDCs revealed that none of the three antigens blocked monocyte differentiation to DCs. The monocytes of 7-day-old cultures showed increased sensitivity to these antigens. The Eg.ferritin induced more mature DCs, which expressed high levels of MHC II and costimulatory molecules, and secreted Th1 cytokines. Eg10 and Eg.mMDH induced lower degrees of DC maturation, however differentiated DCs were in a semi-mature state due to low expression of MHC II and costimulatory molecules and secretion of higher Th2 and lower Th1 cytokines., Conclusion: Eg.ferritin promotes full maturation of DCs and induces Th1 immune response, whereas Eg.10 and Eg.mMDH induce semi-mature DCs producing higher levels of Th2 cytokines.

Autophagy is a promising target for promoting neural regeneration, which is essential for sensorimotor recovery following traumatic brain injury (TBI). Whether neuronal heat shock protein B2 (HSPB2), a small molecular heat shock protein, reduces injury and promotes recovery following TBI remains unclear. In this study, we demonstrated that HSPB2 was significantly increased in the neurons of a TBI mouse model, patients, and primary neuron cultures subjected to oxygen/glucose deprivation and reperfusion treatment. Upon creating a tamoxifen-induced neuron-specific HSPB2 overexpression transgenic mouse model, we found that elevated HSPB2 levels promoted long-term sensorimotor recovery and alleviated tissue loss after TBI. We also demonstrated that HSPB2 enhanced white matter structural and functional integrity, promoted central nervous system (CNS) plasticity, and accelerated long-term neural remodeling. Moreover, we found that autophagy occurred around injured brain tissues in patients, and the pro-regenerative effects of HSPB2 relied on its autophagy-promoting function. Mechanistically, HSPB2 may regulate autophagy possibly by forming the HSPB2/BCL2-associated athanogene 3/sequestosome-1 complex to facilitate the clearance of erroneously accumulated proteins in the axons. Treatment with the autophagy inhibitor chloroquine during the acute stage or delayed induction of HSPB2 remarkably impeded HSPB2's long-term reparative function, indicating the importance of acute-stage autophagy in long-term neuro-regeneration. Our findings highlight the beneficial role of HSPB2 in neuro-regeneration and functional recovery following acute CNS injury, thereby emphasizing the therapeutic potential of autophagy regulation for enhancing neuro-regeneration.

Introduction: The Notch signaling pathway is involved in the development of many diseases; it regulates the development of dendritic cells (DCs), and affects the immune response of DC-mediated T cells. We previously found that ferritin and malate dehydrogenase (mMDH) in Echinococcus granulosus (E.granulosus) induced different immune responses through sensitized DCs. Therefore, in the study we explored whether the Notch signaling pathway affects the development and differentiation of DCs, causing changes in the immune response of DCs sensitized with E. granulosus antigens, and clarified whether it is involved in E.granulosus infection., Methods: We used the Notch signaling pathway inhibitor [N-[3,5-difluorophenace-tyl] -L-alanyl]-S-phenylglycinet-butyl ester (DAPT) or activator Jagged1 to construct in vitro cell models with blocked or activated Notch signaling respectively. We analyzed the effect of Notch signaling on the development and differentiation of DCs by detecting their morphology, migration function, capacity to promote T cell proliferation, and cytokine secretion. We observed the changes in DC response to E. granulosus antigens and the mediated immune response., Results: DAPT inhibited the development and maturation of DCs, which were in a non-responsive or incompetent state, reduced the sensitization of DCs to Eg.ferritin, weakened the migration ability of DCs, disrupted their ability to mediate T-cell proliferation, reduced DC expression of MHCII, CD80, CD60, and CD40 co-stimulatory molecules, prevented the secretion of cytokines and attenuated the expression of Notch1, Notch2, Notch3 receptors, Jagged1, Delta-like 4 (Delta4), and Hes1. Following Jagged1 addition, the function of DCs was restored to some extent, and the expression of Notch1, Delta4 and Hes1 was activated in response to the stimulation of Eg.ferritin. However, Eg.mMDH stimulated DCs to produce an immune response showing weak interference by DAPT and Jagged1., Discussion: The study suggests that the Notc h signaling pathway is involved in the Eg.ferritin-sensitized DC-mediated immune response, which may become a new target for treating E.granulosus infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Shang, Qiao, Hei, Ma and Wang.)

Over the years, widespread interest has been placed on rheological properties to reflect the processability of propellant slurries. Particle gradation technology plays an essential role in the improvement of the processability of propellant slurries. In this article, rheological properties of glycidyl azide polymer (GAP) propellant slurries were measured by dynamic rheological measurements with a rheometer. Submicron-sized ( d 50 = 0.221 μm) and micron-sized ( d 50 = 33.02 μm) CL-20 particles and ultrafine ( d 50 = 2.40 μm) and micron-sized ( d 50 = 341.69 μm) AP particles were utilized to investigate the influence of the addition of CL-20 and particle size gradation on rheological properties. The test results demonstrate that the LVE region remains almost invariable while the yield transition process is delayed when the relative content of submicron-sized CL-20 increases from 10 to 20%. The values of G ', G ″, and |η*| increase with increasing submicron-sized CL-20. Despite this, the value of |η*| can be effectively reduced to about the same value as the slurries with bimodal AP by the size gradation of CL-20. In addition, particle porosity appears to be a suitable parameter to predict trends concerning the rheological properties of the GAP propellant slurries., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

The spread of coronavirus disease 2019 posed a public health crisis beginning in January 2020, affecting hospitals and health care personnel worldwide and disrupting perioperative services. Organization leaders at Xijing Hospital, Xi'an, China, developed a mitigation system for the OR that involved creating a pandemic response team to identify and implement appropriate infection control practices to prevent virus transmission. The leaders addressed managing the daily surgery schedule through patient screening and a focus on the urgency and volume of procedures. They required increased use of personal protective equipment and more stringent cleaning and disinfection protocols and ensured that the physical and mental health of staff members were monitored and prioritized. This article describes how leaders implemented these enhanced processes to protect personnel from infection as they continued to provide patient care. It also describes how high-risk procedures involving patients with confirmed or suspected infections were managed and discusses lessons learned., (© AORN, Inc, 2022.)

Background: Impairments in upper limb motor function and cognitive ability are major health problems experienced by stroke patients, necessitating the development of novel and effective treatment options in stroke care. The aim of this study is to examine the effects of robot-assisted therapy on improving upper limb and cognitive functions in stroke patients., Methods: This will be a single-blinded, 2-arm, parallel design, randomized controlled trial which will include a sample size of 86 acute and subacute stroke patients to be recruited from a single clinical hospital in Shanghai, China. Upon qualifying the study eligibility, participants will be randomly assigned to receive either robot-assisted therapy or conventional therapy with both interventions being conducted over a 6-week period in a clinical rehabilitation setting. In addition to comprehensive rehabilitation, the robot-assisted therapy group will receive a 30-min Armguider robot-assisted therapy intervention 5 days a week. Primary efficacy outcomes will include Fugl-Meyer Assessment for Upper Extremity (FMA-UE) and Mini-Mental Status Examination (MMSE). Other secondary outcomes will include Trail Making Test (TMT), Auditory Verbal Learning Test (AVLT), Digit Symbol Substitution Test (DSST), and Rey-Osterrieth Complex Figure Test (ROCFT). All trial outcomes will be assessed at baseline and at 6-week follow-up. Intention-to-treat analyses will be performed to examine changes from baseline in the outcomes. Adverse events will be monitored throughout the trial period., Discussion: This will be the first randomized controlled trial aimed at examining the effects of robot-assisted therapy on upper limb and cognitive functions in acute and subacute stroke patients. Findings from the study will contribute to our understanding of using a novel robotic rehabilitation approach to stroke care and rehabilitation., Trial Registration: Chinese Clinical Trial Registry ChiCTR2100050856 . Registered on 5 September 2021., (© 2022. The Author(s).)

Echinococcus granulosus causes echinococcosis, an important zoonotic disease worldwide and a major public health issue. Vaccination is an economical and practical approach for controlling E. granulosus. We have previously revealed that a recombinant protein P29 (rEg.P29) is a good vaccine candidate against E. granulosus. However, T cell immunogenic epitopes have not been identified. In the present study, we use rEg.P29-immunized mice as models to screen immunogenic epitopes for the construction of a novel multi-epitope vaccine. We search for immunodominant epitopes from an overlapping peptide library to screen the peptides of rEg.P29. Our results confirm that rEg.P29 immunization in mice elicits the activation of T cells and induces cellular immune responses. Further analyses show that a T cell epitope within amino acids 86–100 of rEg.P29 elicits significant antigen-specific IFN-γ production in CD4+ and CD8+ T cells and promotes specific T-cell activation and proliferation. Collectively, these results provide a reference for the construction of a novel vaccine against broad E. granulosus genotypes based on epitopes of rEg.P29.

High circulating levels of lactate and high mobility group box-1 (HMGB1) are associated with the severity and mortality of sepsis. However, it is unclear whether lactate could promote HMGB1 release during sepsis. The present study demonstrated a novel role of lactate in HMGB1 lactylation and acetylation in macrophages during polymicrobial sepsis. We found that macrophages can uptake extracellular lactate via monocarboxylate transporters (MCTs) to promote HMGB1 lactylation via a p300/CBP-dependent mechanism. We also observed that lactate stimulates HMGB1 acetylation by Hippo/YAP-mediated suppression of deacetylase SIRT1 and β-arrestin2-mediated recruitment of acetylases p300/CBP to the nucleus via G protein-coupled receptor 81 (GPR81). The lactylated/acetylated HMGB1 is released from macrophages via exosome secretion which increases endothelium permeability. In vivo reduction of lactate production and/or inhibition of GPR81-mediated signaling decreases circulating exosomal HMGB1 levels and improves survival outcome in polymicrobial sepsis. Our results provide the basis for targeting lactate/lactate-associated signaling to combat sepsis., (© 2021. The Author(s).)

The tedious sample preparation for flow cytometry limits the throughput and thus its usage as a primary screening method despite its sensitivity and accuracy. With the growing focus on utilizing antibodies as a therapeutic modality in drug discovery, it is critical to develop a high-throughput flow cytometry (HTFC) workflow to cope with the increasing need to support antibody discovery programs. We have developed a seamless HTFC sample preparation and readout workflow using the HighRes modular robotic system and the IntelliCyt iQue Screener PLUS. To fully utilize the advantages offered by flow cytometry, we typically multiplex multiple cell lines of interest in one well to simultaneously quantitate on-target activity and nonspecific activity along with measurement of antibody concentration. The ability to measure multiple parameters coupled with speed and increased accuracy provides gains in productivity and helps speed up antibody lead discovery.

A novel scaly Sn3O4/TiO2 nanobelt heterostructured photocatalyst was fabricated via a facile hydrothermal route. The scaly Sn3O4 nanoflakes can be synthesized in situ and assembled on surface coarsened TiO2 nanobelts through a hydrothermal process. The morphology and distribution of Sn3O4 nanoflakes can be well-controlled by simply tuning the Sn/Ti molar ratio of the reactants. Compared with single phase nanostructures of Sn3O4 and TiO2, the scaly hybrid nanobelts exhibited markedly enhanced photoelectrochemical (PEC) response, which caused higher photocatalytic hydrogen evolution even without the assistance of Pt as a co-catalyst, and enhanced the degradation ability of organic pollutants under both UV and visible light irradiation. In addition to the increased exposure of active facets and broad light absorption, the outstanding performance is ascribed to the matching energy band structure between Sn3O4 and TiO2 at the two sides of the heterostructure, which efficiently reduces the recombination of photo-excited electron-hole pairs and prolongs the lifetime of charge carriers. Both photocatalytic assessment and PEC tests revealed that Sn3O4/TiO2 heterostructures with a molar ratio of Sn/Ti of 2/1 exhibited the highest photocatalytic activity. This study provides a facile and low-cost method for the large scale production of Sn3O4 based materials in various applications.

A method for the determination of diethylstilbestrol (DES), hexestrol (HEX) and dienestrol (DS) residues in drinking water was established by on-line solid phase extraction (SPE) coupled with high performance liquid chromatography (HPLC). The material synthesized on the base of sol-gel technology was employed as adsorbent. This material was prepared using 3-aminopropyltriethoxysilane (APTES) as the functional monomer, tetraethoxysilane (TEOS) as the crosslinking agent, and acetic acid as the initiator. The synthesized adsorbent showed outstanding property for the estrogen extraction. The estrogen can be caught effectively from water samples and the extraction can be achieved rapidly. Some important parameters, such as pH of sample solution, eluent solvents, loading flow rate, which might influence extraction efficiency, were optimized. The results indicated that the limit of detection (S/N = 3) of the developed method could reach 0.07-0.13 microg/L under the conditions of pH 7.0 of sample solution, methanol and 1% (v/v) acetic acid aqueous solution as the eluent solvent and the loading flow rate of 2 mL/min. The recoveries of the three estrogens from the water samples at three spiked levels ranged from 82.31% to 99.43% with RSD of 1.61%-7.15%. The method was simple, rapid, and suitable to detect the trace residues of estrogens in drinking water.

Spatial and temporal concentration gradients of chemoattractants direct many biological processes, especially the guidance of immune cells to tissue sites during homeostasis and responses to infection. Such gradients are ultimately generated by secretion of attractant proteins from single cells or collections of cells. Here we describe cell-sized chemoattractant-releasing polysaccharide microspheres, capable of mimicking chemokine secretion by host cells and generating sustained bioactive chemokine gradients in their local microenvironment. Exploiting the common characteristic of net cationic charge and reversible glycosaminoglycan binding exhibited by many chemokines, we synthesized alginate hydrogel microspheres that could be loaded with several different chemokines (including CCL21, CCL19, CXCL12, and CXCL10) by electrostatic adsorption. These polysaccharide microspheres subsequently released the attractants over periods ranging from a few hours to at least 1 day when placed in serum-containing medium or collagen gels. The generated gradients were able to attract cells more than hundreds of microns away to make contact with individual microspheres. This versatile system for chemoattractant delivery could find applications in immunotherapy, vaccines and fundamental chemotaxis studies in vivo and in vitro., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Cell movement biased by a chemical gradient, or chemotaxis, coordinates the recruitment of cells and collective migration of cell populations. During wound healing, chemotaxis of fibroblasts is stimulated by platelet-derived growth factor (PDGF) and certain other chemoattractants. Whereas the immediate PDGF gradient sensing response has been characterized previously at the level of phosphoinositide 3-kinase (PI3K) signaling, the sensitivity of the response at the level of cell migration bias has not yet been studied quantitatively. In this work, we used live-cell total internal reflection fluorescence microscopy to monitor PI3K signaling dynamics and cell movements for extended periods. We show that persistent and properly aligned (i.e., high-fidelity) fibroblast migration does indeed correlate with polarized PI3K signaling; accordingly, this behavior is seen only under conditions of high gradient steepness (>10% across a typical cell length of 50 μm) and a certain range of PDGF concentrations. Under suboptimal conditions, cells execute a random or biased random walk, but nonetheless move in a predictable fashion according to the changing pattern of PI3K signaling. Inhibition of PI3K during chemotaxis is accompanied by loss of both cell-substratum contact and morphological polarity, but after a recovery period, PI3K-inhibited fibroblasts often regain the ability to orient toward the PDGF gradient., (Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.)

We recently described a strategy for intracellular delivery of macromolecules, utilizing pH-responsive "core-shell" structured gel particles. These cross-linked hydrogel particles disrupt endosomes with low toxicity by virtue of physical sequestration of an endosome-disrupting "proton sponge" core inside a nontoxic hydrophilic shell. Here we tested the efficacy of this system for cytosolic delivery of a broad range of macromolecular cargos, and demonstrate the delivery of proteins, whole viral particles, or siRNA oligonucleotides into the cytosol of dendritic cells and epithelial cells via core-shell particles. We assessed the functional impact of particle delivery for vaccine applications and found that cytosolic delivery of protein antigens in dendritic cells via the core-shell particles promotes priming of CD8(+) T-cells at 100-fold lower doses than soluble protein. Functional gene knockdown following delivery of siRNA using the particles was demonstrated in epithelial cells. Based on these findings, these materials may be of interest for a broad range of biomedical applications.