Diffusion Tensor MRI is sensitive to fibrotic injury in a mouse model of oxalate induced chronic kidney disease.

Chronic kidney disease (CKD) is characterized by inflammation and fibrosis in the kidney. Renal biopsies and estimated glomerular filtration rate (eGFR) remain the standard of care, but these endpoints have limitations in detecting the stage, progression, and spatial distribution of fibrotic pathology in the kidney. MRI diffusion tensor imaging (DTI) has emerged as a promising non-invasive technology to evaluate renal fibrosis in vivo both in clinical and preclinical studies. However, these imaging studies have not systematically identified fibrosis particularly deeper in the kidney where biopsy sampling is limited, or completed an extensive analysis of whole organ histology, blood biomarkers, and gene expression to evaluate the relative strengths and weaknesses of MRI for evaluating renal fibrosis. In this study, we performed DTI in the sodium oxalate mouse model of CKD. The DTI parameters fractional anisotropy, apparent diffusion coefficient, and axial diffusivity were compared between the control and oxalate groups with region-of-interest (ROI) analysis to determine changes in the cortex and medulla. Additionally, voxel-based analysis (VBA) was implemented to systematically identify local regions of injury over the whole kidney. DTI parameters were found to be significantly different in the medulla by both ROI analysis and VBA, which also spatially matched with collagen III IHC. The DTI parameters in this medullary region exhibited moderate to strong correlations with histology, blood biomarkers, hydroxyproline and gene expression. Our results thus highlight the sensitivity of DTI to the heterogeneity of renal fibrosis and importance of whole kidney non-invasive imaging.

Autophagosome-lysosome fusion is facilitated by plectin-stabilized actin and keratin 8 during macroautophagic process.

Autophagy is a lysosome-mediated degradative process that removes damaged proteins and organelles, during which autophagosome-lysosome fusion is a key step of the autophagic flux. Based on our observation that intermediate cytofilament keratin 8 (KRT8) enhances autophagic clearance in cells under oxidative stress condition, we investigated whether KRT8 supports the cytoplasmic architectural networks to facilitate the vesicular fusion entailing trafficking onto filamentous tracks. We found that KRT8 interacts with actin filaments via the cytolinker, plectin (PLEC) during trafficking of autophagosome. When PLEC was knocked down or KRT8 structure was collapsed by phosphorylation, autophagosome-lysosome fusion was attenuated. Inhibition of actin polymerization resulted in accumulation of autophagosomes owing to a decrease in autophagosome and lysosome fusion. Furthermore, myosin motor protein was found to be responsible for vesicular trafficking along the actin filaments to entail autolysosome formation. Thus, the autophagosome-lysosome fusion is aided by PLEC-stabilized actin filaments as well as intermediate cytofilament KRT8 that supports the structural integrity of actin filaments during macroautophagic process under oxidative stress condition.

Mesoporous Silica Particle as an RNA Adsorbent for Facile Purification of In Vitro-Transcribed RNA.

Messenger RNA vaccines against SARS-CoV-2 hold great promise for the treatment of a wide range of diseases by using mRNA as a tool for generating vaccination antigens as well as therapeutic proteins in vivo. Increasing interest in mRNA preparation warrants reliable methods for in vitro transcription (IVT) of mRNA, which must entail the elimination of surplus side products such as immunogenic double-stranded RNA (dsRNA). We developed a facile method for the removal of dsRNA from in vitro transcribed RNA with mesoporous silica particles as RNA adsorbents. Various polyamines were tested for the facilitation of RNA adsorption onto mesoporous silica particles in the chromatography. Among the polyamines tested for RNA adsorption, spermidine showed a superior capability of RNA binding to the silica matrix. Mesoporous silica-adsorbed RNA was readily desorbed with elution buffer containing either salt, EDTA, or urea, possibly by disrupting electrostatic interaction and hydrogen bonding between RNA and the silica matrix. Purification of IVT RNA was enabled with the adsorption of RNA to mesoporous silica in a spermidine-containing buffer and subsequent elution with EDTA. By differing EDTA concentration in the eluting buffer, we demonstrated that at least 80% of the dsRNA can be removed from the mesoporous silica-adsorbed RNA. When compared with the cellulose-based removal of dsRNA from IVT RNA, the mesoporous silica-based purification of IVT RNA using spermidine and EDTA in binding and elution, respectively, exhibited more effective removal of dsRNA contaminants from IVT RNA. Thus, mRNA purification with mesoporous silica particles as RNA adsorbents is applicable for the facile preparation of nonimmunogenic RNA suitable for in vivo uses.

A Novel Time-Resolved Fluorescence Resonance Energy Transfer Assay for the Discovery of Small-Molecule Inhibitors of HIV-1 Tat-Regulated Transcription.

Human immunodeficiency virus-1 (HIV-1) transactivator (Tat)-mediated transcription is essential for HIV-1 replication. It is determined by the interaction between Tat and transactivation response (TAR) RNA, a highly conserved process representing a prominent therapeutic target against HIV-1 replication. However, owing to the limitations of current high-throughput screening (HTS) assays, no drug that disrupts the Tat-TAR RNA interaction has been uncovered yet. We designed a homogenous (mix-and-read) time-resolved fluorescence resonance energy transfer (TR-FRET) assay using europium cryptate as a fluorescence donor. It was optimized by evaluating different probing systems for Tat-derived peptides or TAR RNA. The specificity of the optimal assay was validated by mutants of the Tat-derived peptides and TAR RNA fragment, individually and by competitive inhibition with known TAR RNA-binding peptides. The assay generated a constant Tat-TAR RNA interaction signal, discriminating the compounds that disrupted the interaction. Combined with a functional assay, the TR-FRET assay identified two small molecules (460-G06 and 463-H08) capable of inhibiting Tat activity and HIV-1 infection from a large-scale compound library. The simplicity, ease of operation, and rapidity of our assay render it suitable for HTS to identify Tat-TAR RNA interaction inhibitors. The identified compounds may also act as potent molecular scaffolds for developing a new HIV-1 drug class.

Recent Trends in Lateral Flow Immunoassays with Optical Nanoparticles.

Rapid, accurate, and convenient diagnosis is essential for effective disease management. Various detection methods, such as enzyme-linked immunosorbent assay, have been extensively used, with lateral flow immunoassay (LFIA) recently emerging as a major diagnostic tool. Nanoparticles (NPs) with characteristic optical properties are used as probes for LFIA, and researchers have presented various types of optical NPs with modified optical properties. Herein, we review the literature on LFIA with optical NPs for the detection of specific targets in the context of diagnostics.

Comparative Evaluation of the Efficacy of Combined Intramedullary Pinning with K-Wires Pinning in the Treatment of Fifth Metacarpal Neck Fractures versus Conventional Techniques-K-Wires Pinning and Intramedullary Pinning.

Background and Objectives: Since the neck is the weakest part of the metacarpals, the most common metacarpal fracture is a neck fracture, a type which accounts for 38% of all hand fractures. Such fractures can be fixed using a variety of conventional techniques, including intramedullary pinning and K-wire pinning. However, conventional techniques involve complications, such as angulation, stiffness, and rotational deformity. The purpose of this study was to compare the usefulness of our new technique, combined intramedullary pinning with K-wire pinning (IPKP), with those of intramedullary pinning (IP) and K-wire pinning (KP). Materials and Methods: This was a single-center, randomized controlled trial conducted between January 2005 and April 2023. A total of 158 patients with acute displaced fractures of the fifth-metacarpal neck were randomly assigned to either the IPKP group (n = 48), the KP group (n = 60), or the IP group (n = 50). We radiographically evaluated angulation and shortening in three visits: pre-operatively, post-operatively, and at a 1-year follow-up. We clinically evaluated the ranges of motion and Quick-DASH scores to assess daily living performance and the cosmetic scores, using the SBSES score, to assess patients' satisfaction with their cosmetic outcomes. Results: The IPKP group was superior to the KP group and the IP group regarding radiographical and clinical assessments at the 1-year follow-up visit. The angulation was 15.7° (±7.7) in the KP group, 17.0° (±5.9) in the IP group, and 12.6° (±2.5) in the IPKP group (p < 0.001) at the 1-year follow-up visit. The shortening was 0.9 mm (±0.3) in the KP group, 1.4 mm (±0.2) in the IP group, and 0.4 mm (±0.1) in the IPKP group (m < 0.001) at the 1-year follow-up visit. The TAM was 272.6° (±17.5) in the KP group, 271.1° (±18.0) in the IP group, and 274.1° (±14.9) in the IPKP group (p = 0.42). Four patients (6.6%) in the KP group and two patients (4%) in the IP group were reported as having stiffness, while no patients were found to have stiffness in the IPKP group. The average Quick-DASH score was 2.3 (±0.5) in the KP group, 2.5 (±0.4) in the IP group, and 1.9 (±0.4) in the IPKP group (p > 0.05). The average cosmetic score was 3.7 (±1.2) in the KP group, 3.8 (±0.9) in the IP group, and 4.7 (±0.8) in the IPKP group (p < 0.001). A complication involving nonunion occurred in one case (1.6%) in the KP group, while there were three cases (6%) of rotational deformity in the IP groups. Conclusions: With the IPKP technique, accurate reduction can be achieved to improve hand function and cosmetic outcomes.

Inhibition of immunoproteasome attenuates NLRP3 inflammasome formation in tumor necrosis factor α-stimulated intestinal epithelial cell.

Excessive release of inflammatory cytokines has been considered as a major cause of chronic inflammation, resulting in intestinal barrier disruption that leads to inflammatory bowel disease (IBD). Tumor necrosis factor α (TNFα) is one of the well-known inflammatory cytokines that activates formation of NLRP3 inflammasome, thus resulting in excessive secretion of inflammatory cytokines causing IBD. Although immunoproteasome inhibitors have been reported to inhibit inflammatory cytokine release, immunoproteasome inhibition has not yet been addressed for attenuation of NLRP3 inflammasome activity in intestinal epithelial cell. Here, we observed that NLRP3 inflammasome assembly was attenuated by peptide epoxyketone YU102, a LMP2 subunit immunoproteasome inhibitor, in intestinal epithelial cell. YU102 also inhibited maturation of active caspase-1 and secretion of IL-1ß, which are subsequent inflammatory cascade after the formation of NLRP3 inflammasome. Progression of epithelial-mesenchymal transition and increase of cellular permeability, which were induced by TNFα, were also suppressed through inhibition of immunoproteasome. Furthermore, we found that YU102 does not inhibit degradation of IкBα and its following NF-кB activation that leads to transcription of NLRP3. These findings suggest that inhibition of immunoproteasome with YU102 offers a potential therapeutic premise for prevention of TNFα-induced chronic inflammation through attenuation of NLRP3 inflammasome assembly.

Highly sensitive near-infrared SERS nanoprobes for in vivo imaging using gold-assembled silica nanoparticles with controllable nanogaps.

BACKGROUND: To take advantages, such as multiplex capacity, non-photobleaching property, and high sensitivity, of surface-enhanced Raman scattering (SERS)-based in vivo imaging, development of highly enhanced SERS nanoprobes in near-infrared (NIR) region is needed. A well-controlled morphology and biocompatibility are essential features of NIR SERS nanoprobes. Gold (Au)-assembled nanostructures with controllable nanogaps with highly enhanced SERS signals within multiple hotspots could be a breakthrough. RESULTS: Au-assembled silica (SiO2) nanoparticles (NPs) (SiO2@Au@Au NPs) as NIR SERS nanoprobes are synthesized using the seed-mediated growth method. SiO2@Au@Au NPs using six different sizes of Au NPs (SiO2@Au@Au50-SiO2@Au@Au500) were prepared by controlling the concentration of Au precursor in the growth step. The nanogaps between Au NPs on the SiO2 surface could be controlled from 4.16 to 0.98 nm by adjusting the concentration of Au precursor (hence increasing Au NP sizes), which resulted in the formation of effective SERS hotspots. SiO2@Au@Au500 NPs with a 0.98-nm gap showed a high SERS enhancement factor of approximately 3.8 × 106 under 785-nm photoexcitation. SiO2@Au@Au500 nanoprobes showed detectable in vivo SERS signals at a concentration of 16 µg/mL in animal tissue specimen at a depth of 7 mm. SiO2@Au@Au500 NPs with 14 different Raman label compounds exhibited distinct SERS signals upon subcutaneous injection into nude mice. CONCLUSIONS: SiO2@Au@Au NPs showed high potential for in vivo applications as multiplex nanoprobes with high SERS sensitivity in the NIR region.

Highly Bright Silica-Coated InP/ZnS Quantum Dot-Embedded Silica Nanoparticles as Biocompatible Nanoprobes.

Quantum dots (QDs) have outstanding optical properties such as strong fluorescence, excellent photostability, broad absorption spectra, and narrow emission bands, which make them useful for bioimaging. However, cadmium (Cd)-based QDs, which have been widely studied, have potential toxicity problems. Cd-free QDs have also been studied, but their weak photoluminescence (PL) intensity makes their practical use in bioimaging challenging. In this study, Cd-free QD nanoprobes for bioimaging were fabricated by densely embedding multiple indium phosphide/zinc sulfide (InP/ZnS) QDs onto silica templates and coating them with a silica shell. The fabricated silica-coated InP/ZnS QD-embedded silica nanoparticles (SiO2@InP QDs@SiO2 NPs) exhibited hydrophilic properties because of the surface silica shell. The quantum yield (QY), maximum emission peak wavelength, and full-width half-maximum (FWHM) of the final fabricated SiO2@InP QDs@SiO2 NPs were 6.61%, 527.01 nm, and 44.62 nm, respectively. Moreover, the brightness of the particles could be easily controlled by adjusting the amount of InP/ZnS QDs in the SiO2@InP QDs@SiO2 NPs. When SiO2@InP QDs@SiO2 NPs were administered to tumor syngeneic mice, the fluorescence signal was prominently detected in the tumor because of the preferential distribution of the SiO2@InP QDs@SiO2 NPs, demonstrating their applicability in bioimaging with NPs. Thus, SiO2@InP QDs@SiO2 NPs have the potential to successfully replace Cd-based QDs as highly bright and biocompatible fluorescent nanoprobes.

Identification of 3-Oxindole Derivatives as Small Molecule HIV-1 Inhibitors Targeting Tat-Mediated Viral Transcription.

The heterocyclic indole structure has been shown to be one of the most promising scaffolds, offering various medicinal advantages from its wide range of biological activity. Nonetheless, the significance of 3-oxindole has been less known. In this study, a series of novel 3-oxindole-2-carboxylates were synthesized and their antiviral activity against human immunodeficiency virus-1 (HIV-1) infection was evaluated. Among these, methyl (E)-2-(3-chloroallyl)-4,6-dimethyl-one (6f) exhibited the most potent inhibitory effect on HIV-1 infection, with a half-maximal inhibitory concentration (IC50) of 0.4578 µM but without severe cytotoxicity (selectivity index (SI) = 111.37). The inhibitory effect of these compounds on HIV-1 infection was concordant with their inhibitory effect on the viral replication cycle. Mode-of-action studies have shown that these prominent derivatives specifically inhibited the Tat-mediated viral transcription on the HIV-1 LTR promoter instead of reverse transcription or integration. Overall, our findings indicate that 3-oxindole derivatives could be useful as a potent scaffold for the development of a new class of anti-HIV-1 agents.

Label-free fluorometric detection of influenza viral RNA by strand displacement coupled with rolling circle amplification.

Since influenza occurs globally every year, it is important to develop a facile and accurate method to detect the influenza virus. This study aimed at developing a sensitive fluorometric assay for detecting influenza viral RNA through tandem gene amplification methods including reverse transcription PCR (RT-PCR), followed by strand displacement amplification (SDA) coupled with rolling circle amplification (RCA). Influenza viral RNA was initially amplified by RT-PCR with a tailed reverse primer containing an additional sequence for SDA. The RT-PCR amplicon was then subjected to SDA, yielding multiple copies of single-stranded DNA (ssDNA) that can be used as a primer for subsequent RCA. Thereafter, a long ssDNA segment harboring tandem repeated G-quadruplexes that were generated through RCA was intercalated by Thioflavin T, yielding a strong fluorescence signal indicating the presence of the target viral RNA. Fluorometric analysis detected influenza viral RNA ranging from 50 pg to 500 pg with a limit of detection of 6.2 pg with a signal-to-background ratio of 10 and identified each influenza virus strain (H1N1, H3N2, and influenza B). Thus, the present method for the label-free fluorometric detection of viral RNA via tandem gene amplifications combining RT-PCR-coupled SDA and G-quadruplex-generating RCA would facilitate the efficient diagnosis of influenza infection.

Cyclin-Dependent Kinase Inhibitor BMI-1026 Induces Apoptosis by Downregulating Mcl-1 (L) and c-FLIP (L) and Inactivating p-Akt in Human Renal Carcinoma Cells.

Previous studies have investigated the inhibitory effect of BMI-1026 on cyclin-dependent kinase 1 in vitro. However, the molecular mechanisms by which BMI-1026 treatment leads to cancer cell death remain unclear. This study was conducted to investigate the anticancer mechanisms of BMI-1026 on human renal carcinoma Caki cells. BMI-1026 induced apoptosis in association with the cleavage of poly(ADP-ribose) polymerase and pro-caspase-3 and the release of apoptosis-inducing factor and cytochrome c from mitochondria in Caki cells. BMI-1026-induced apoptosis was inhibited by the pan-caspase inhibitor z-VAD-fmk. Furthermore, BMI-1026 downregulated Bcl-2 and X-linked inhibitor of apoptosis protein (XIAP) at the transcriptional level and Mcl-1 (L) and cellular FADD-like IL-1ß-converting enzyme inhibitory protein (c-FLIP (L)) at the post-transcriptional level. Interestingly, Mcl-1 (L) and c-FLIP (L), but not Bcl-2 or XIAP, played important roles in BMI-1026-induced Caki cell apoptosis. Although the constitutively active form of Akt did not attenuate BMI-1026-induced apoptosis, blockade of the PI3K/Akt pathway using a subcytotoxic concentration of the PI3K/Akt inhibitor LY294002 enhanced Caki cell apoptosis induced by BMI-1026. Electrophysiological safety was confirmed by determining the cardiotoxicity of BMI-1026 via left ventricular pressure analysis. These results suggest that BMI-1026 is a potent multitarget anticancer agent with electrophysiological safety and should be further investigated.

The bacterial endoribonuclease RNase E can cleave RNA in the absence of the RNA chaperone Hfq.

RNase E is a component of the RNA degradosome complex and plays a key role in RNA degradation and maturation in Escherichia coli RNase E-mediated target RNA degradation typically involves the RNA chaperone Hfq and requires small guide RNAs (sRNAs) acting as a seed by binding to short (7-12-bp) complementary regions in target RNA sequences. Here, using recombinantly expressed and purified proteins, site-directed mutagenesis, and RNA cleavage and protein cross-linking assays, we investigated Hfq-independent RNA decay by RNase E. Exploring its RNA substrate preferences in the absence of Hfq, we observed that RNase E preferentially cleaves AU-rich sites of single-stranded regions of RNA substrates that are annealed to an sRNA that contains a monophosphate at its 5'-end. We further found that the quaternary structure of RNase E is also important for complete, Hfq-independent cleavage at sites both proximal and distal to the sRNA-binding site within target RNAs containing monophosphorylated 5'-ends. Of note, genetic RNase E variants with unstable quaternary structure exhibited decreased catalytic activity. In summary, our results show that RNase E can degrade its target RNAs in the absence of the RNA chaperone Hfq. We conclude that RNase E-mediated, Hfq-independent RNA decay in E. coli requires a cognate sRNA sequence for annealing to the target RNA, a 5'-monophosphate at the RNA 5'-end, and a stable RNase E quaternary structure.

Identification of novel compounds against Tat-mediated human immunodeficiency virus-1 transcription by high-throughput functional screening assay.

Trans-activator (Tat)-mediated human immunodeficiency virus type 1 (HIV-1) transcription is essential for the replication of HIV-1 and is considered a potent therapeutic target for HIV-1 inhibition. In this study, the Library of Pharmacologically Active Compounds (LOPAC1280) was screened using our dual-reporter screening system for repositioning as Tat-inhibitory compounds. Consequently, two compounds were found to be potent, with low cytotoxicity. Of these two compounds, Roscovitine (CYC202) is already known to be a Tat inhibitor, while gemcitabine has been newly identified as an inhibitor of Tat-mediated transcription linked to viral production and replication. In an additional screening using the ribonucleoside analogues of gemcitabine, two analogues (2'-C-methylcytidine and 3-deazauridine) showed a specific Tat-inhibitory effect linked to their anti-HIV-1 activity. Interestingly, these compounds did not affect Tat protein directly, while the mechanism underlying their inhibition of Tat-mediated transcription was linked to pyrimidine biosynthesis, rather than to alteration of the dNTP pool, influenced by the inhibition of ribonucleotide reductase. Taken together, the proposed functional screening system is a useful tool for the identification of inhibitors of Tat-mediated HIV-1 transcription from among a large number of compounds, and the inhibitory effect of HIV-1 transcription by gemcitabine and its analogues may suggest a strategy for developing a new class of therapeutic anti-HIV drugs.

Label-free fluorometric detection of microRNA using isothermal rolling circle amplification generating tandem G-quadruplex.

MicroRNAs (miRNAs) play an important role in various biological processes and have been regarded as promising diagnostic biomarkers for solid tumors in the field of clinical diagnostics. In this study, we developed a simple label/quencher-free fluorometric system for sensitive and selective miRNA detection using isothermal gene amplification such as rolling circle amplification generating tandem G-quadruplex DNA structures (GQ-RCA). The closed-circular dumbbell-shaped padlock DNA was designed to be complementary to its corresponding target miRNA. In the presence of the target miRNA, a long stretch of ssDNA with tandem G-quadruplex sequence repeats was readily generated by RCA, initiated by phi29 DNA polymerase through DNA synthesis priming at the 3'-OH of the target miRNA annealed to the padlock DNA. The RCA product harboring tandem G-quadruplex was monitored with fluorophore Thioflavin T (ThT) that emits strong fluorescence only when it intercalates into the G-quadruplex. The GQ-RCA assay enabled us to detect miRNA as low as 4.9 fM with a linear range from 25.6 fM to 80 pM within 0.5 h. In addition, our system was applied to the miRNA samples present in human plasma, showing its potential use in the clinical diagnosis of cancer.

Comparative analysis of COVID-19 guidelines from six countries: a qualitative study on the US, China, South Korea, the UK, Brazil, and Haiti.

BACKGROUND: In late January, a worldwide crisis known as COVID-19 was declared a Public Health Emergency of International Concern by the WHO. Within only a few weeks, the outbreak took on pandemic proportions, affecting over 100 countries. It was a significant issue to prevent and control COVID-19 on both national and global scales due to the dramatic increase in confirmed cases worldwide. Government guidelines provide a fundamental resource for communities, as they guide citizens on how to protect themselves against COVID-19, however, they also provide critical guidance for policy makers and healthcare professionals on how to take action to decrease the spread of COVID-19. We aimed to identify the differences and similarities between six different countries' (US, China, South Korea, UK, Brazil and Haiti) government-provided community and healthcare system guidelines, and to explore the relationship between guideline issue dates and the prevalence/incidence of COVID-19 cases. METHODS: To make these comparisons, this exploratory qualitative study used document analysis of government guidelines issued to the general public and to healthcare professionals. Documents were purposively sampled (N = 55) and analyzed using content analysis. RESULTS: The major differences in the evaluation and testing criteria in the guidelines across the six countries centered around the priority of testing for COVID-19 in the general population, which was strongly dependent on each country's healthcare capacity. However, the most similar guidelines pertained to the clinical signs and symptoms of COVID-19, and methods to prevent its contraction. CONCLUSION: In the initial stages of the outbreak, certain strategies were universally employed to control the deadly virus's spread, including quarantining the sick, contact tracing, and social distancing. However, each country dealt with differing healthcare capacities, risks, threats, political and socioeconomic challenges, and distinct healthcare systems and infrastructure. Acknowledging these differences highlights the importance of examining the various countries' response to the COVID-19 pandemic with a nuanced view, as each of these factors shaped the government guidelines distributed to each country's communities and healthcare systems.

Functionalized ß-Cyclodextrin Immobilized on Ag-Embedded Silica Nanoparticles as a Drug Carrier.

Cyclodextrins (CDs) have beneficial characteristics for drug delivery, including hydrophobic interior surfaces. Nanocarriers with ß-CD ligands have been prepared with simple surface modifications as drug delivery vehicles. In this study, we synthesized ß-CD derivatives on an Ag-embedded silica nanoparticle (NP) (SiO2@Ag NP) structure to load and release doxorubicin (DOX). Cysteinyl-ß-CD and ethylenediamine-ß-CD (EDA-ß-CD) were immobilized on the surface of SiO2@Ag NPs, as confirmed by transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectrophotometry, and Fourier transform infrared (FTIR) spectroscopy. DOX was introduced into the ß-CD on the SiO2@Ag NPs and then successfully released. Neither cysteinyl-ß-CD and EDA-ß-CD showed cytotoxicity, while DOX-loaded cysteinyl-ß-CD and EDA-ß-CD showed a significant decrease in cell viability in cancer cells. The SiO2@Ag NPs with ß-CD provide a strategy for designing a nanocarrier that can deliver a drug with controlled release from modified chemical types.

Hispidulin Inhibits Mast Cell-Mediated Allergic Inflammation through Down-Regulation of Histamine Release and Inflammatory Cytokines.

Hispidulin (4',5,7-trihydroxy-6-methoxyflavone) is a natural compound derived from traditional Chinese medicinal herbs, and it is known to have an anti-inflammatory effect. Here, we investigated the effect of hispidulin on the immunoglobulin E (IgE)-mediated allergic responses in rat basophilic leukemia (RBL)-2H3 mast cells. When RBL-2H3 cells were sensitized with anti-dinitrophenyl (anti-DNP) IgE and subsequently stimulated with DNP-human serum albumin (HSA), histamine and ß-hexosaminidase were released from the cells by degranulation of activated mast cells. However, pretreatment with hispidulin before the stimulation of DNP-HSA markedly attenuated release of both in anti-DNP IgE-sensitized cells. Furthermore, we investigated whether hispidulin inhibits anti-DNP IgE and DNP-HSA-induced passive cutaneous anaphylaxis (PCA), as an animal model for Type I allergies. Hispidulin markedly decreased the PCA reaction and allergic edema of ears in mice. In addition, activated RBL-2H3 cells induced the expression of inflammatory cytokines (tumor necrosis factor-α and interleukin-4), which are critical for the pathogenesis of allergic disease, through the activation of c-Jun N-terminal kinase (JNK). Inhibition of JNK activation by hispidulin treatment reduced the induction of cytokine expression in the activated mast cells. Our results indicate that hispidulin might be a possible therapeutic candidate for allergic inflammatory diseases through the suppression of degranulation and inflammatory cytokines expression.

A novel anti-cancer agent, FPDHP, induces anoikis in various human cancer cells through activation of calpain, and downregulation of anoikis-related molecules.

Resistance to anoikis and growth in anchorage-independent conditions are hallmarks of highly metastatic cancer cells. Anoikis is a type of apoptosis induced by inadequate cell/extracellular matrix (ECM) attachment and an attractive anti-cancer therapeutic strategy in cancer chemotherapeutic field. Therefore, the development of anoikis-inducing agents is useful and promising to overcome cancer. When FPDHP, a novel anoikis-inducing agent, was treated within 3 h, FPDHP induced massive cell detachment in various human cancer cells, irrespective of apoptosis. Moreover, FPDHP decreased the expression of integrins, FAK, focal adhesion signaling effectors (talin1 and talin2), tight junction proteins (ZO-1, ZO-2, and ZO-3), transcriptional mediators of epithelial-mesenchymal transition (EMT) (Snail1 and Snail2), and anoikis-related protein, such as Mcl-1 (L). Interestingly, Caki/ZO-2 and Caki/α6 are significantly suppressed the FPDHP-mediated cell detachment, and the constitutive active form of Akt and overexpression of Mcl-1 (L) partially inhibited the cellular detachment induced by FPDHP. On the other hand, when FPDHP was treated for more than 12 h, FPDHP induced caspase-dependent apoptosis and release of AIF and cytochrome c from mitochondria. Furthermore, FPDHP down regulated Mcl-1 (L) at post-transcriptional level, and overexpression of Mcl-1 (L) partially attenuated the apoptosis induced by FPDHP. Additionally, PD150606, a calpain inhibitor, attenuated FPDHP-mediated cell detachment and apoptosis. Taken together, these results suggest that FPDHP possesses anoikis-inducing activity or potential making cancer cells susceptible to anoikis, and may be developed as a novel active compound for cancer treatment.

Polyethylene Glycol-Engrafted Graphene Oxide as Biocompatible Materials for Peptide Nucleic Acid Delivery into Cells.

Graphene oxide (GO) is known to strongly bind single-stranded nucleic acids with fluorescence quenching near the GO surface. However, GO exhibits weak biocompatibility characteristics, such as low dispersibility in cell culture media and significant cytotoxicity. To improve dispersibility in cell culture media and cell viability of GO, we prepared nanosized GO (nGO) constructs and modified the nGO surface using polyethylene glycol (PEG-nGO). Single-stranded peptide nucleic acid (PNA) was adsorbed onto the PEG-nGO and was readily desorbed by adding complementary RNA or under low pH conditions. PNA adsorbed on the PEG-nGO was efficiently delivered into lung cancer cells via endocytosis without affecting cell viability. Furthermore, antisense PNA delivered using PEG-nGO effectively downregulated the expression of the target gene in cancer cells. Our results suggest that PEG-nGO is a biocompatible carrier useful for PNA delivery into cells and serves as a promising gene delivery tool.