New Metric to Evaluate Cardiac Anisotropic Mechanics by Directional High-Frequency Ultrasound-Based Transverse Wave Elastography.

The evaluation of cardiac anisotropic mechanics is important in the diagnosis of heart disease. However, other representative ultrasound imaging-based metrics, which are capable of quantitatively evaluating anisotropic cardiac mechanics, are insufficient for accurately diagnosing heart disease due to the influence of viscosity and geometry of cardiac tissues. In this study, we propose a new ultrasound imaging-based metric, maximum cosine similarity (MaxCosim), for quantifying anisotropic mechanics of cardiac tissues by evaluating the periodicity of the transverse wave speeds depending on the measurement directions using ultrasound imaging. We developed a high-frequency ultrasound-based directional transverse wave imaging system to measure the transverse wave speed in multiple directions. The ultrasound imaging-based metric was validated by performing experiments on 40 rats randomly assigned to four groups; three doxorubicin (DOX) treatment groups received 10, 15, or 20 mg/kg DOX, while the control group received 0.2 mL/kg saline. In each heart sample, the developed ultrasound imaging system allowed measuring transverse wave speeds in multiple directions, and the new metric was then calculated from 3-D ultrasound transverse wave images to evaluate the degree of anisotropic mechanics of the heart sample. The results of the metric were compared with histopathological changes for validation. A decrease in the MaxCosim value was observed in the DOX treatment groups, with the degree of decrease depending on the dose. These results are consistent with the histopathological features, suggesting that our ultrasound imaging-based metric can quantify the anisotropic mechanics of cardiac tissues and potentially be used for the early diagnosis of heart disease.

Facet Connectivity-Based Estimation Algorithm for Manufacturability of Supportless Parts Fabricated via LPBF.

Recent advances in additive manufacturing have provided more freedom in the design of metal parts; hence, the prototyping of fluid machines featuring extremely complex geometries has been investigated extensively. The fabrication of fluid machines via additive manufacturing requires significant attention to part stability; however, studies that predict regions with a high risk of collapse are few. Therefore, a novel algorithm that can detect collapse regions precisely is proposed herein. The algorithm reflects the support span over the faceted surface via propagation and invalidates overestimated collapse regions based on the overhang angle. A heat exchanger model with an extremely complex internal space is adopted to validate the algorithm. Three samples from the model are extracted and their prototypes are fabricated via laser powder bed fusion. The results yielded by the fabricated samples and algorithm with respect to the sample domain are compared. Regions of visible collapse identified on the surface of the fabricated samples are predicted precisely by the algorithm. Thus, the supporting span reflected by the algorithm provides an extremely precise prediction of collapse.

Ex Vivo Evaluation of Mechanical Anisotropic Tissues with High-Frequency Ultrasound Shear Wave Elastography.

The use of imaging devices to assess directional mechanics of tissues is highly desirable. This is because the directional mechanics depend on fiber orientation, and altered directional mechanics are closely related to the pathological status of tissues. However, measuring directional mechanics in tissues with high-stiffness is challenging due to the difficulty of generating localized displacement in these tissues using acoustic radiation force, a general method for generating displacement in ultrasound-based elastography. In addition, common ultrasound probes do not provide rotational function, which makes the measurement of directional mechanics inaccurate and unreliable. Therefore, we developed a high-frequency ultrasound mechanical wave elastography system that can accommodate a wide range of tissue stiffness and is also equipped with a motorized rotation stage for precise imaging of directional mechanics. A mechanical shaker was applied to the elastography system to measure tissues with high-stiffness. Phantom and ex vivo experiments were performed. In the phantom experiments, the lateral and axial resolution of the system were determined to be 144 µm and 168 µm, respectively. In the ex vivo experiments, we used swine heart and cartilage, both of which are considered stiff. The elastography system allows us to acquire the directional mechanics with high angular resolution in the heart and cartilage. The results demonstrate that the developed elastography system is capable of imaging a wide range of tissues and has high angular resolution. Therefore, this system might be useful for the diagnostics of mechanically anisotropic tissues via ex vivo tests.

Review of the Effects of Supplementary Cementitious Materials and Chemical Additives on the Physical, Mechanical and Durability Properties of Hydraulic Concrete.

Supplementary cementitious materials (SCMs) and chemical additives (CA) are incorporated to modify the properties of concrete. In this paper, SCMs such as fly ash (FA), ground granulated blast furnace slag (GGBS), silica fume (SF), rice husk ash (RHA), sugarcane bagasse ash (SBA), and tire-derived fuel ash (TDFA) admixed concretes are reviewed. FA (25-30%), GGBS (50-55%), RHA (15-20%), and SBA (15%) are safely used to replace Portland cement. FA requires activation, while GGBS has undergone in situ activation, with other alkalis present in it. The reactive silica in RHA and SBA readily reacts with free Ca(OH)2 in cement matrix, which produces the secondary C-S-H gel and gives strength to the concrete. SF addition involves both physical contribution and chemical action in concrete. TDFA contains 25-30% SiO2 and 30-35% CaO, and is considered a suitable secondary pozzolanic material. In this review, special emphasis is given to the various chemical additives and their role in protecting rebar from corrosion. Specialized concrete for novel applications, namely self-curing, self-healing, superhydrophobic, electromagnetic (EM) wave shielding and self-temperature adjusting concretes, are also discussed.

Korean Red Ginseng enhances pneumococcal Δpep27 vaccine efficacy by inhibiting reactive oxygen species production.

BACKGROUND: Streptococcus pneumoniae, more than 90 serotypes of which exist, is recognized as an etiologic agent of pneumonia, meningitis, and sepsis associated with significant morbidity and mortality worldwide. Immunization with a pneumococcal pep27 mutant (Δpep27) has been shown to confer comprehensive, long-term protection against even nontypeable strains. However, Δpep27 is effective as a vaccine only after at least three rounds of immunization. Therefore, treatments capable of enhancing the efficiency of Δpep27 immunization should be identified without delay. Panax ginseng Mayer has already been shown to have pharmacological and antioxidant effects. Here, the ability of Korean Red Ginseng (KRG) to enhance the efficacy of Δpep27 immunization was investigated. METHODS: Mice were treated with KRG and immunized with Δpep27 before infection with the pathogenic S. pneumoniae strain D39. Total reactive oxygen species production was measured using lung homogenates, and inducible nitric oxide (NO) synthase and antiapoptotic protein expression was determined by immunoblotting. The phagocytic activity of peritoneal macrophages was also tested after KRG treatment. RESULTS: Compared with the other treatments, KRG significantly increased survival rate after lethal challenge and resulted in faster bacterial clearance via increased phagocytosis. Moreover, KRG enhanced Δpep27 vaccine efficacy by inhibiting reactive oxygen species production, reducing extracellular signal-regulated kinase apoptosis signaling and inflammation. CONCLUSION: Taken together, our results suggest that KRG reduces the time required for immunization with the Δpep27 vaccine by enhancing its efficacy.

ATF3 Stimulates IL-17A by Regulating Intracellular Ca2+/ROS-Dependent IL-1ß Activation During Streptococcus pneumoniae Infection.

Activating transcription factor-3 (ATF3) in the ER stress pathway induces cytokine production and promotes survival during gram-positive bacterial infection. IL-17A is a critical cytokine that is essential for clearance of Streptococcus pneumoniae. However, the mechanism by which ATF3 induces IL-17A production remains unknown. Here, we show that ATF3 induces IL-17A production via NLRP3 inflammasome-dependent IL-1ß secretion. Survival rates were comparable in IL-17A-depleted and ATF3 KO mice but were lower than in WT mice treated with isotype control, indicating that ATF3 positively regulated IL-17A production. Indeed, ATF3 KO mice showed a marked reduction in IL-17A protein and mRNA expression compared to levels in WT mice. Moreover, mitochondrial IL-1ß production by bone marrow-derived macrophages was significantly reduced in ATF3 KO mice as a result of the disruption of cellular ROS and Ca2+ homeostasis. Accordingly, ATF3 KO mice displayed diminished survival and bacterial clearance following S. pneumoniae infection. Taken together, these data suggest a mechanism in which macrophage ATF3 promotes IL-17A production in γδ T cells to rapidly induce host defenses during early S. pneumoniae infection.

Induction of the pneumococcal vncRS operon by lactoferrin is essential for pneumonia.

Streptococcus pneumoniae (pneumococcus), the major pathogen for pneumonia, commonly colonizes the lung, but the mechanism underlying the coordination of virulence factors during invasion via the host protein remains poorly understood. Bacterial lysis releases the components of the cell wall, and triggers innate immunity and the subsequent secretion of pro-inflammatory cytokines. Previously, the virulence of the pep27 mutant was shown to be attenuated as a feasible candidate for vaccine development. However, the role of pep27 gene, belonging to the vancomycin-resistance locus (vncRS operon), in virulence, is largely unknown. This study demonstrates that transferrin in the host serum reduces the survival of the host during S. pneumoniae infections in mice. The exposure of the pneumococcal D39 strain to lactoferrin induced the vncRS operon, lysis, and subsequent in vivo cytokine production, resulting in lung inflammation. However, these responses were significantly attenuated in pneumococci harboring a mutation in pep27. Mechanistically, the VncS ligand, identified as lactoferrin, induced the vncRS operon and increased the in vivo mortality rates. Thus, serum-induced activation of vncRS plays an essential role in inducing pneumonia.

Pulmonary Colonization Resistance to Pathogens via Noncanonical Wnt and Interleukin-17A by Intranasal pep27 Mutant Immunization.

Background: Previous studies have focused on colonization resistance of the gut microbiota against antibiotic resistant strains. However, less research has been performed on respiratory colonization resistance. Methods: Because respiratory colonization is the first step of respiratory infections, intervention to prevent colonization would represent a new approach for preventive and therapeutic measures. The Th17 response plays an important role in clearance of respiratory pathogens. Thus, harnessing the Th17 immune response in the mucosal site would be an effective method to design a respiratory mucosal vaccine. Results: In this study, we show that intranasal Δpep27 immunization induces noncanonical Wnt and subsequent interleukin (IL)-17 secretion, and it inhibits Streptococcus pneumoniae, Staphylococcus aureus, and Klebsiella pneumoniae colonization. Moreover, IL-17A neutralization or nuclear factor of activated T-cell inhibition augmented bacterial colonization, indicating that noncanonical Wnt signaling is involved in pulmonary colonization resistance. Conclusions: Therefore, Δpep27 immunization can provide nonspecific respiratory colonization resistance via noncanonical Wnt signaling and IL-17A-related pathways.

Estrogen receptor-ß of microglia underlies sexual differentiation of neuronal protection via ginsenosides in mice brain.

AIMS: Streptococcus pneumoniae infection in acute bacterial meningitis can lead to widespread brain damage and mortality. Inflammatory responses by immune cells in the brain are thought to determine the degree of brain injury. Yet, the mechanisms underlying host responses to pneumococcal meningitis are largely unknown. To explore host responses as a potential therapeutic target for preventing brain injury after pneumococcal meningitis. METHODS: We evaluated signaling mechanisms that minimize neuronal damage caused by pneumococcal infection; specifically, we assessed pathways related to neuronal survival after enhancing estrogen receptor-ß (ER-ß) expression using a natural therapeutic substance known as ginsenoside Rb1 and Rg3 enhanced ginseng. RESULTS: Tissue damage caused by bacterial infection was reduced in Rb1/Rg3-treated mice as a result of microglial activation and the inhibition of apoptosis. Furthermore, Rb1 upregulated the expression of brain-derived neurotrophic factor (BDNF) as well as anti-apoptotic factors including Bcl-2 and Bcl-xL. Using BV2 microglial cells in vitro, Rb1 treatment inhibited microglial apoptosis in a manner associated with JAK2/STAT5 phosphorylation. CONCLUSION: After S. pneumoniae infection in mice, particularly in female mice, Rb1-containing ginseng increased bacterial clearance and survival. These findings inform our understanding of the host immune response to pneumococcal meningitis.

Inhibition of Autolysis by Lipase LipA in Streptococcus pneumoniae Sepsis.

More than 50% of sepsis cases are associated with pneumonia. Sepsis is caused by infiltration of bacteria into the blood via inflammation, which is triggered by the release of cell wall components following lysis. However, the regulatory mechanism of lysis during infection is not well defined. Mice were infected with Streptococcus pneumoniae D39 wild-type (WT) and lipase mutant (ΔlipA) intranasally (pneumonia model) or intraperitoneally (sepsis model), and survival rate and pneumococcal colonization were determined. LipA and autolysin (LytA) levels were determined by qPCR and western blotting. S. pneumoniae Spd_1447 in the D39 (type 2) strain was identified as a lipase (LipA). In the sepsis model, but not in the pneumonia model, mice infected with the ΔlipA displayed higher mortality rates than did the D39 WT-infected mice. Treatment of pneumococci with serum induced LipA expression at both the mRNA and protein levels. In the presence of serum, the ΔlipA displayed faster lysis rates and higher LytA expression than the WT, both in vitro and in vivo. These results indicate that a pneumococcal lipase (LipA) represses autolysis via inhibition of LytA in a sepsis model.

Effects of ginseng on stress-related depression, anxiety, and the hypothalamic-pituitary-adrenal axis.

Ginseng effectively regulates the immune response and the hormonal changes due to stress, thus maintaining homeostasis. In addition to suppressing the occurrence of psychological diseases such as anxiety and depression, ginseng also prevents stress-associated physiological diseases. Recent findings have revealed that ginseng is involved in adjusting the hypothalamic-pituitary-adrenal axis and controlling hormones, thus producing beneficial effects on the heart and brain, and in cases of bone diseases, as well as alleviating erectile dysfunction. Recent studies have highlighted the potential use of ginseng in the prevention and treatment of chronic inflammatory diseases such as diabetes, rheumatoid arthritis, and allergic asthma. However, the mechanism underlying the effects of ginseng on these stress-related diseases has not been completely established. In this review, we focus on the disease pathways caused by stress in order to determine how ginseng acts to improve health. Central to our discussion is how this effective and stable therapeutic agent alleviates the anxiety and depression caused by stress and ameliorates inflammatory diseases.

Effect of decreased BCAA synthesis through disruption of ilvC gene on the virulence of Streptococcus pneumoniae.

Streptococcus pneumoniae (pneumococcus) is responsible for significant morbidity and mortality worldwide. It causes a variety of life-threatening infections such as pneumonia, bacteremia, and meningitis. In bacterial physiology, the metabolic pathway of branched-chain amino acids (BCAAs) plays an important role in virulence. Nonetheless, the function of IlvC, one of the enzymes involved in the biosynthesis of BCAAs, in S. pneumoniae remains unclear. Here, we demonstrated that downregulation of BCAA biosynthesis by ilvC ablation can diminish BCAA concentration and expression of pneumolysin (Ply) and LytA, and subsequently attenuate virulence. Infection with an ilvC mutant showed significantly reduced mortality and colonization in comparison with strain D39 (serotype 2, wild type), suggesting that ilvC can potentiate S. pneumoniae virulence due to adequate BCAA synthesis. Taken together, these results suggest that the function of ilvC in BCAA synthesis is essential for virulence factor and could play an important role in the pathogenesis of respiratory infections.

Molecular characterization of a single-chain antibody variable fragment (scFv) specific for PspA from Streptococcus pneumoniae.

Streptococcus pneumoniae is a major infectious agent responsible for pneumonia, otitis media, sepsis and meningitis. Pneumococcal surface protein A (PspA) is a well-characterized virulence factor localized on the surface and a target for vaccine development. In this study, we screened a single-chain antibody variable fragment (scFv) using phage display from a human synthetic library to select a clone 2B11. Affinity (Kd) of 2B11 was measured to be 5 nM using biolayer interferometry. 2B11 exhibited a dose-dependent recognition of recombinant PspA with no cross-reactivity towards pneumococcal antigens. The epitope on PspA was defined to residues 231-242 by mutational analysis. Molecular docking analysis supported the experimentally determined epitope, suggesting that the helix spanning residues 231-242 can bind to 2B11 with residues in the CDR-H3 (complementarity determining region 3 in the heavy chain) actively participating in the molecular contacts. Comparison of 2B11 with a commercial PspA antibody revealed that 2B11 exhibited a better specificity towards recombinant PspA antigen. 2B11 was capable of detecting endogenous PspA from pneumococcal lysates with affinity similar to that of the commercial antibody. Our study provides a molecular tool for biosensors detecting pneumococcal diseases.

Pneumococcal pep27 mutant immunization stimulates cytokine secretion and confers long-term immunity with a wide range of protection, including against non-typeable strains.

Streptococcus pneumoniae is comprised of more than 90 serotypes and is the major causative agent of pneumonia, which results in over 1million deaths worldwide every year. Currently available injectable vaccines can protect against only 13-23 serotypes, and result in decrease of colonization against vaccine serotypes. However, they are neither effective for inhibition of non-vaccine serotypes colonization nor inhibition against initial colonization in the nasopharynx against various serotypes. Thus, development of a vaccine conveying broader protection at the colonization stage is required. This study examined whether the Δpep27 mutant could provide protection at the nasopharynx against a broad range of serotypes. Δpep27 immunization stimulated secretion of IL-4, IL-10, TNF-α, INF-γ and IL-17, and significantly increased secretory-IgA levels in bronchoalveolar lavage fluid. Colonization and opsonophagocytosis assays demonstrated that Δpep27 immunization could protect against many heterologous infections, including non-typeable strains, at the nasopharynx, and prompted efficient killing of heterologous strains, suggesting that Δpep27 immunization provides a wide range of cross-protection. Furthermore, Δpep27 immunization significantly increased both the survival rate and the level of IgG 3months post-immunization, demonstrating long-lasting immunity. Thus, Δpep27 could serve as a highly feasible mucosal vaccine once it is further developed into a non-transformable strain.

ATF3 provides protection from Staphylococcus aureus and Listeria monocytogenes infections.

Activating transcription factor 3 (ATF3) is a stress-induced transcriptional regulator in eukaryote. The role of ATF3 in cancer has been well defined, but how ATF3 functions in bacterial infection is not well understood. Pneumococcal infection has been shown to induce ATF3 expression, which subsequently enhances cytokine production and provides protection from lethal Streptococcus pneumoniae infection, but the role of ATF3 in other Gram-positive (G(+)) infections remains unclear. Here, we report that infection with other G(+) bacteria (Staphylococcus aureus and Listeria monocytogenes) and with G(-) bacteria (uropathogenic Escherichia coli) also significantly induced ATF3 expression. Moreover, the production of cytokines (tumor necrosis factor alpha [TNF]-α, interleukin [IL]-1ß, IL-6 and interferon [IFN]-γ) was enhanced by ATF3 in S. aureus and L. monocytogenes infection, but decreased in uropathogenic E. coli (UPEC) infection. In addition, in S. aureus and L. monocytogenes infections, ATF3 WT mice cleared bacteria more efficiently and had higher survival rates than ATF3 knockout mice. However, in UPEC infection, no significant difference was found in survival rate. Taken together, these data suggest that ATF3 provides protection from S. aureus and L. monocytogenes infections; however, the role of ATF3 in UPEC infection is more complicated and should be further elucidated.

ß-lapachone suppresses the proliferation of human malignant melanoma cells by targeting specificity protein 1.

ß-lapachone (ß-lap), a novel natural quinone derived from the bark of the Pink trumpet tree (Tabebuia avellanedae) has been demonstrated to have anticancer activity. In this study, we investigated whether ß-lap exhibits anti-proliferative effects on two human malignant melanoma (HMM) cell lines, G361 and SK-MEL-28. The effects of ß-lap on the HMM cell lines were investigated using 3-(4,5-dimethylthiazol-2-yl)­5-(3-carboxymethoxyphenyl)­2-(4-sulfophenyl-2H-tetrazolium (MTS) assay, 4',6-diamidino-2-phenylindole (DAPI) staining, Annexin V and Dead cell assay, mitochondrial membrane potential (MMP) assay and western blot analysis. We demonstrated that ß-lap significantly induced apoptosis and suppressed cell viability in the HMM cells. Intriguingly, the transcription factor specificity protein 1 (Sp1) was significantly downregulated by ß-lap in a dose- and time-dependent manner. Furthermore, ß-lap modulated the protein expression level of the Sp1 regulatory genes including cell cycle regulatory proteins and apoptosis-associated proteins. Taken together, our findings indicated that ß-lap modulates Sp1 transactivation and induces apoptotic cell death through the regulation of cell cycle- and apoptosis-associated proteins. Thus, ß-lap may be used as a promising anticancer drug for cancer prevention and may improve the clinical outcome of patients with cancer.

Esculetin Induces Apoptosis Through EGFR/PI3K/Akt Signaling Pathway and Nucleophosmin Relocalization.

Esculetin, a coumarin compound, has anti-proliferative effects on various types of human cancer cells, but its effect on oral squamous cell carcinoma (OSCC) is unknown. In this study, we determined whether esculetin had anti-proliferative effects on two oral squamous cell lines, HN22, and HSC2. We found that esculetin inhibited cell viability by inducing apoptosis, as evinced by apoptotic cell morphologies, nuclear fragmentation, and the multi-caspase/MMP activity. Furthermore, proteomic analysis was used to identify the target-specific proteins involved in esculetin treatment. Intriguingly, apoptotic cell death by esculetin was associated with significant inhibition of the EGFR/PI3K/Akt signaling pathway. We also demonstrated that the expression of nucleophosmin (NPM) markedly decreased after esculetin treatment, and relocalization of NPM from the nucleous to the cytoplasm, together with p65, potentiated apoptotic stimulation. Additionally, our data indicated that NPM expression was markedly higher in OSCC tissues than in normal tissues. Our results collectively indicated that esculetin inhibited the proliferation of OSCC through EGFR-mediated signaling pathways and down-regulation of NPM as well as the perturbation of NPM trafficking from the nucleolus to the cytoplasm resulted in apoptosis.

Fibroblast growth factor-4 enhances proliferation of mouse embryonic stem cells via activation of c-Jun signaling.

Fibroblast growth factor-4 (FGF4) is expressed in embryonic stages and in adult tissues, where it plays critical roles in modulating multiple cellular functions. However, the exact roles of FGF4 on proliferation and differentiation of embryonic stem cells (ESCs) are not completely understood. Exogenous addition of FGF4 stimulated proliferation of mouse ESCs (mESCs), as proven by the increases in DNA synthesis and cell cycle regulatory protein induction. These increases were almost completely inhibited by pre-treating cells with anti-FGF4 antibody. FGF4 also activated c-Jun N-terminal kinase (JNK) and extracellular-signal regulated kinase (ERK) signaling, but not p38 kinase. Blockage of JNK signaling by SP600125 or by transfection with its specific siRNA significantly inhibited FGF4-stimulated cell proliferation through the suppression of c-Jun induction and activator protein-1 (AP-1) activity. However, ERK or p38 kinase inhibitor did not affect FGF4-stimulated proliferation in mESCs. FGF4 suppressed osteogenic differentiation of mESCs by inhibiting expression of transcription factors involved in bone formation. Further, exogenous FGF4 addition stimulated proliferation of human periodontal ligament stem cells (hPDLSCs) and bone marrow mesenchymal stem cells (BMMSCs) via activation of ERK signaling. FGF4 also augmented mineralization of hPDLSCs, but not of BMMSCs. Collectively, it is suggested that FGF4 triggers proliferation of stem cells by activating MAPK-mediated signaling, while it affects differently osteogenic differentiation according to the origins of stem cells.

Can botulinum toxin improve mood in depressed patients?

Depression has a number of significant symptoms such as depressed mood, lack of volition/energy, suicidal ideation, low concentration, sleep disturbance, anger, anxiety, psychomotor retardation, fear and sadness. In addition, various facial expressions such as frowning and sadness can also be easily recognized in depressed patients. In fact, major muscles involved in the development of such negative emotion have been reported in depressed patients, for instance, corrugators and procerus muscles in the glabellar regions of the face. Electromyography studies have also reported that depressed patients had overactivity of such grief muscles during different affective imagery paradigms. Furthermore, subjective emotion has also been found to be affected by differential facial expression via an image feedback system. Interestingly, anecdotal open-label studies have shown that botulinum toxin may have a role in treatment of depression and a recent randomized-placebo controlled study has also confirmed the effect of botulinum toxin in reduction of depressive symptoms for the first time. This article will discuss the putative role of botulinum toxin in a treatment of depression in the context of the clinical significance, limitations and future research directions.