Improving NanoCluster Beacon performance by blocking the unlabeled NC probes

While NanoCluster Beacon (NCB) is a versatile molecular probe, it suffers from a low target-specific signal issue due to impurities. Here we show that adding a "blocker" strand to the reaction can effectively block the nonfunctional probes and enhance the target-specific signal by 14 fold at a 0.1 target/probe ratio.

Antrocin Sensitizes Prostate Cancer Cells to Radiotherapy through Inhibiting PI3K/AKT and MAPK Signaling Pathways

Radiotherapy is one of the most common treatment options for local or regional advanced prostate cancer (PCa). Importantly, PCa is prone to radioresistance and often develops into malignancies after long-term radiotherapy. Antrocin, a sesquiterpene lactone isolated from Antrodia cinnamomea, possesses pharmacological efficacy against various cancer types; however, its therapeutic potential requires comprehensive exploration, particularly in radioresistant PCa cells. In this study, we emphasized the effects of antrocin on radioresistant PCa cells and addressed the molecular mechanism underlying the radiosensitization induced by antrocin. Our results showed that a combination treatment with antrocin and ionizing radiation (IR) synergistically inhibited cell proliferation and induced apoptosis in radioresistant PCa cells. We further demonstrated that antrocin downregulated PI3K/AKT and MAPK signaling pathways as well as suppressed type 1 insulin-like growth factor 1 receptor (IGF-1R)-mediated induction of β-catenin to regulate cell cycle and apoptosis. Using xenograft mouse models, we showed that antrocin effectively enhanced radiotherapy in PCa. Our study demonstrates that antrocin sensitizes PCa to radiation through constitutive suppression of IGF-1R downstream signaling, revealing that it can be developed as a potent therapeutic agent to overcome radioresistant PCa.

Evaluation of the action of Tween 20 non-ionic surfactant during enzymatic hydrolysis of lignocellulose: Pretreatment, hydrolysis conditions and lignin structure

The aim of this work was to study the effects of pretreatment process, hydrolysis condition and structural features of lignin on the improving action of surfactants (Tween 20) for enzymatic hydrolysis of pretreated wheat straw, and further to interpret the relation of these factors with the non-productive adsorption of cellulases on lignin. Tween 20 seemed to be more greatly improve cellulose conversion under harsher conditions. The surfactant showed more significant improvement for acid-pretreated substrates than oxidative-pretreated substrates. Highly-condensed lignin and phenolic hydroxyl groups showed much stronger adsorption ability to cellulases, while Tween 20 could well block the lignin-cellulase interactions recovering cellulose hydrolyzability. It was proposed that pretreatments altered lignin structures, resulting in the change of surface properties thus further impacting the lignin-cellulase interactions. Addition of Tween 20 could modify lignin surface properties to change its hydrophobicity, hydrogen bonding ability and surface charges, thus reducing the non-productive adsorption of proteins.

Helicobacter pylori cholesterol glucosylation modulates autophagy for increasing intracellular survival in macrophages

Cholesterol-α-glucosyltransferase (CGT) encoded by the type 1 capsular polysaccharide biosynthesis protein J (capJ) gene of Helicobacter pylori converts cellular cholesterol into cholesteryl glucosides. H. pylori infection induces autophagy that may increase bacterial survival in epithelial cells. However, the role of H. pylori CGT that exploits lipid rafts in interfering with autophagy for bacterial survival in macrophages has not been investigated. Here, we show that wild-type H. pylori carrying CGT modulates cholesterol to trigger autophagy and restrain autophagosome fusion with lysosomes, permitting a significantly higher bacterial burden in macrophages than that in a capJ-knockout (∆CapJ) mutant. Knockdown of autophagy-related protein 12 impairs autophagosome maturation and decreases the survival of internalised H. pylori in macrophages. These results demonstrate that CGT plays a crucial role in the manipulation of the autophagy process to impair macrophage clearance of H. pylori.

WWOX Phosphorylation, Signaling, and Role in Neurodegeneration

Homozygous null mutation of tumor suppressor WWOX/Wwox gene leads to severe neural diseases, metabolic disorders and early death in the newborns of humans, mice and rats. WWOX is frequently downregulated in the hippocampi of patients with Alzheimer’s disease (AD). In vitro analysis revealed that knockdown of WWOX protein in neuroblastoma cells results in aggregation of TRAPPC6AΔ, TIAF1, amyloid β, and Tau in a sequential manner. Indeed, TRAPPC6AΔ and TIAF1, but not tau and amyloid β, aggregates are present in the brains of healthy mid-aged individuals. It is reasonable to assume that very slow activation of a protein aggregation cascade starts sequentially with TRAPPC6AΔ and TIAF1 aggregation at mid-ages, then caspase activation and APP de-phosphorylation and degradation, and final accumulation of amyloid β and Tau aggregates in the brains at greater than 70 years old. WWOX binds Tau-hyperphosphorylating enzymes (e.g., GSK-3β) and blocks their functions, thereby supporting neuronal survival and differentiation. As a neuronal protective hormone, 17β-estradiol (E2) binds WWOX at an NSYK motif in the C-terminal SDR (short-chain alcohol dehydrogenase/reductase) domain. In this review, we discuss how WWOX and E2 block protein aggregation during neurodegeneration, and how a 31-amino-acid zinc finger-like Zfra peptide restores memory loss in mice.

Highly Efficient 2D/3D Hybrid Perovskite Solar Cells via Low-Pressure Vapor-Assisted Solution Process

The fabrication of multidimensional organometallic halide perovskite via a low-pressure vapor-assisted solution process is demonstrated for the first time. Phenyl ethyl-ammonium iodide (PEAI)-doped lead iodide (PbI₂ ) is first spin-coated onto the substrate and subsequently reacts with methyl-ammonium iodide (MAI) vapor in a low-pressure heating oven. The doping ratio of PEAI in MAI-vapor-treated perovskite has significant impact on the crystalline structure, surface morphology, grain size, UV-vis absorption and photoluminescence spectra, and the resultant device performance. Multiple photoluminescence spectra are observed in the perovskite film starting with high PEAI/PbI₂ ratio, which suggests the coexistence of low-dimensional perovskite (PEA₂ MA_n-1 Pb_n I_3n+1 ) with various values of n after vapor reaction. The dimensionality of the as-fabricated perovskite film reveals an evolution from 2D, hybrid 2D/3D to 3D structure when the doping level of PEAI/PbI₂ ratio varies from 2 to 0. Scanning electron microscopy images and Kelvin probe force microscopy mapping show that the PEAI-containing perovskite grain is presumably formed around the MAPbI₃ perovskite grain to benefit MAPbI₃ grain growth. The device employing perovskite with PEAI/PbI₂ = 0.05 achieves a champion power conversion efficiency of 19.10% with an open-circuit voltage of 1.08 V, a current density of 21.91 mA cm^-2 , and a remarkable fill factor of 80.36%.

Simvastatin Sensitizes Radioresistant Prostate Cancer Cells by Compromising DNA Double-Strand Break Repair

Prostate cancer (PCa) is one of the most prevalent male cancers in western world. Radiation therapy (RT) is commonly used to treat PCa patients. However, a certain proportion of patients develop radioresistant PCa cells, which results in metastatic disease. Statins, which inhibit 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase, are commonly used to treat hypercholesterolemia, exhibiting beneficial effects on cardiovascular diseases and on several types of cancers, including PCa. However, the mechanistic details and crosstalk between statins and RT in PCa cells remain unknown. In this study, radioresistant DOC-2/DAB2 interactive protein (DAB2IP)-deficient PCa cells were used to evaluate whether simvastatin could enhance the effect of ionizing radiation (IR). The crucial molecules that associated with simvastatin elevated radiosensitivity in PCa cells were explored. Our results demonstrated that a combination treatment with simvastatin and IR synergistically induced apoptosis of radioresistant PCa cells. In addition, simvastatin appeared to compromise DNA double-strand breaks repair by activating the expressions of histone 2A family member X (γ-H2AX) and phospho-checkpoint kinase 1 (p-CHK1), suggesting an underlying mechanism for this radiosensitization of PCa cells. These findings reveal that simvastatin may be a potent therapeutic agent for co-treatment with radiation to overcome radioresistance in PCa cells.

Lagged Influence of Fine Particulate Matter and Geographic Disparities on Clinic Visits for Children's Asthma in Taiwan

Recent studies have revealed the influence of fine particulate matter (PM_2.5) on increased medication use, hospital admission, and emergency room visits for asthma attack in children, but the lagged influence of PM_2.5 on children’s asthma and geographic disparities of children’s asthma have rarely been discussed simultaneously. This study investigated the documented diagnosis of children’s asthma in clinic visits for children aged less than 15 years old that were associated with PM_2.5 in two counties located in west-central Taiwan during 2005–2010. The result shows that PM_2.5 had a significant lagged effect on children’s asthma for up to 6 days. A significantly higher relative risk for children’s asthma was more likely to happen at 2-day lag compared to the present day when PM_2.5 increased from 36.17 μg/m³ to 81.26 μg/m³. Considering all lagged effects, the highest relative risk for children’s asthma was 1.08 (95% CI = 1.05, 1.11) as PM_2.5 increased as high as 64.66 μg/m³. In addition, geographic disparities of children’s asthma were significant, and 47.83% of areas were identified to have children vulnerable to asthma. To sum up, our findings can serve as a valuable reference for the implementation of an early warning to governmental agencies about a susceptible population of children.

Simvastatin Therapy for Drug Repositioning to Reduce the Risk of Prostate Cancer Mortality in Patients With Hyperlipidemia

Prostate cancer (PCa) is one of the most commonly diagnosed cancers in the western world, and the mortality rate from PCa in Asia has been increasing recently. Statins are potent inhibitors of 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase and are commonly used for treating hyperlipidemia, with beneficial effects for cardiovascular disease and they also exhibit anti-cancer activity. However, the protective effects of statins against PCa are controversial. In this study, we investigated the effect of two types of statins (simvastatin and lovastatin) and the mortality rate of PCa patients by using the Taiwan National Health Insurance Research Database (NHIRD). A total of 15,264 PCa patients with hyperlipidemia records and medical claims from the Registry of Catastrophic Illness were enrolled. The patients were divided into two cohorts based on their statin use before the diagnosis of PCa: statin users (n = 1,827) and non-statin users (n = 1,826). The results showed that patients who used statins exhibited a significantly reduced risk of mortality from PCa [adjusted hazard ratio (HR) = 0.84, 95% CI = 0.73–0.97]. Analysis of the cumulative defined daily dose (DDD) indicated that patients who were prescribed simvastatin ≥ 180 DDD had a dramatically decreased risk of death from PCa (adjusted HR = 0.63; 95% CI = 0.51–0.77). This population-based cohort study demonstrated that statin use significantly decreased the mortality of PCa patients, and that this risk was inversely associated with the cumulative DDD of simvastatin therapy. The results of this study revealed that statins may be used for drug repositioning and in the development of a feasible approach to prevent death from PCa.

Recent progress in GM-CSF-based cancer immunotherapy

Cancer immunotherapy is a growing field. GM-CSF, a potent cytokine promoting the differentiation of myeloid cells, can also be used as an immunostimulatory adjuvant to elicit antitumor immunity. Additionally, GM-CSF is essential for the differentiation of dendritic cells, which are responsible for processing and presenting tumor antigens for the priming of antitumor cytotoxic T lymphocytes. Some strategies have been developed for GM-CSF-based cancer immunotherapy in clinical practice: GM-CSF monotherapy, GM-CSF-secreting cancer cell vaccines, GM-CSF-fused tumor-associated antigen protein-based vaccines, GM-CSF-based DNA vaccines and GM-CSF combination therapy. GM-CSF also contributes to the regulation of immunosuppression in the tumor microenvironment. This review provides recommendations regarding GM-CSF-based cancer immunotherapy.

Cytolethal Distending Toxin Enhances Radiosensitivity in Prostate Cancer Cells by Regulating Autophagy

Cytolethal distending toxin (CDT) produced by Campylobacter jejuni contains three subunits: CdtA, CdtB, and CdtC. Among these three toxin subunits, CdtB is the toxic moiety of CDT with DNase I activity, resulting in DNA double-strand breaks (DSB) and, consequently, cell cycle arrest at the G2/M stage and apoptosis. Radiation therapy is an effective modality for the treatment of localized prostate cancer (PCa). However, patients often develop radioresistance. Owing to its particular biochemical properties, we previously employed CdtB as a therapeutic agent for sensitizing radioresistant PCa cells to ionizing radiation (IR). In this study, we further demonstrated that CDT suppresses the IR-induced autophagy pathway in PCa cells by attenuating c-Myc expression and therefore sensitizes PCa cells to radiation. We further showed that CDT prevents the formation of autophagosomes via decreased high-mobility group box 1 (HMGB1) expression and the inhibition of acidic vesicular organelle (AVO) formation, which are associated with enhanced radiosensitivity in PCa cells. The results of this study reveal the detailed mechanism of CDT for the treatment of radioresistant PCa.

LNA Thymidine Monomer Enables Differentiation of the Four Single-Nucleotide Variants by Melting Temperature

High-resolution melting (HRM) analysis of DNA is a closed-tube single-nucleotide polymorphism (SNP) detection method that has shown many advantages in point-of-care diagnostics and personalized medicine. While recently developed melting probes have demonstrated significantly improved discrimination of mismatched (mutant) alleles from matched (wild-type) alleles, no effort has been made to design a simple melting probe that can reliably distinguish all four SNP alleles in a single experiment. Such a new probe could facilitate the discovery of rare genetic mutations at lower cost. Here we demonstrate that a melting probe embedded with a single locked thymidine monomer (t_L) can reliably differentiate the four SNP alleles by four distinct melting temperatures (termed the "4T_m probe"). This enhanced discriminatory power comes from the decreased melting temperature of the t_L·C mismatched hybrid as compared to that of the t·C mismatched hybrid, while the melting temperatures of the t_L-A, t_L·G and t_L·T hybrids are increased or remain unchanged as compared to those of their canonical counterparts. This phenomenon is observed not only in the HRM experiments but also in the molecular dynamics simulations.

3D single-molecule tracking enables direct hybridization kinetics measurement in solution

Single-molecule measurements of DNA hybridization kinetics are mostly performed on a surface or inside a trap. Here we demonstrate a time-resolved, 3D single-molecule tracking (3D-SMT) method that allows us to follow a freely diffusing ssDNA molecule in solution for hundreds of milliseconds or even seconds and observe multiple annealing and melting events taking place on the same molecule. This is achieved by combining confocal-feedback 3D-SMT with time-domain fluorescence lifetime measurement, where fluorescence lifetime serves as the indicator of hybridization. With sub-diffraction-limit spatial resolution in molecular tracking and 15 ms temporal resolution in monitoring the change of reporter's lifetime, we have demonstrated a full characterization of annealing rate (kon = 5.13 × 106 M-1 s-1), melting rate (koff = 9.55 s-1), and association constant (Ka = 0.54 μM-1) of an 8 bp duplex model system diffusing at 4.8 μm2 s-1. As our method completely eliminates the photobleaching artifacts and diffusion interference, our kon and koff results well represent the real kinetics in solution. Our binding kinetics measurement can be carried out in a low signal-to-noise ratio condition (SNR ≈ 1.4) where ∼130 recorded photons are sufficient for a lifetime estimation. Using a population-level analysis, we can characterize hybridization kinetics over a wide range (0.5-125 s-1), even beyond the reciprocals of the lifetime monitoring temporal resolution and the average track duration.

Statin Therapy Is Associated with Reduced Risk of Peptic Ulcer Disease in the Taiwanese Population

Although statin use may affect the severity of chronic gastritis and gastric cancer, no data exists about the relationship between statin therapy and risk of peptic ulcer disease (PUD) in patients. We investigated the effect of statin use and the incidence of PUD from the Taiwan National Health Insurance Research Database (NHIRD). A total of 35,194 patients records for medical claims were enrolled. We performed a population-based case-control analysis to compare the incidence of PUD in patients who were prescribed statins and that in patients who were not. In the univariate logistic analysis, we found that statin was not significant risk of PUD. However, a multivariate model indicates that satin use was significantly associated with a reduced risk of PUD (adjusted odds ratio [aOR] = 0.87, 95% CI = 0.82-0.93, P < 0.001). The cumulative defined daily dose (DDD) was analyzed. Patients who prescribed fluvastatin ≥280 DDD, atorvastatin ≥200 DDD, and pravastatin ≥130 DDD dramatically decreased risk for PUD (aOR = 0.58, 0.67, and 0.71; 95% CI = 0.46-0.74, 0.57-0.78, and 0.56-0.91, respectively). Our results showed that statin therapy reduced the risk of PUD and this was associated with the high cumulative DDD of prescribed statins. This study reveals that active use of statins to be associated with decreased risk for PUD.

Self-adjustment and disintegration threshold of Langmuir solitons in inhomogeneous plasmas

Dynamics of Langmuir solitons in the presence of a background density gradient is investigated numerically, including cases with steep gradients to the extent the solitons can disintegrate. The disintegration threshold is explained by regarding the electric field part of the soliton as a point mass moving along the self-generated potential well corresponding to the density cavity. On the other hand, it is demonstrated that the Langmuir solitons are robust when the density gradient is below the threshold. During the acceleration phase toward low density regions, Langmuir solitons adjust themselves to balance the electric field pressure and the negative plasma pressure by expelling the imbalanced portion as density cavities at the sound velocity. When the density gradient is below the disintegration threshold, the electric field part of the soliton bounces back and forth within the potential well suggesting the solitons have internal structures.

Sensitization of Radioresistant Prostate Cancer Cells by Resveratrol Isolated from Arachis hypogaea Stems

Resveratrol (RV, 3,4ʹ,5-trihydroxystilbene) is naturally produced by a wide variety of plants including grapes and peanuts (Arachis hypogaea). However, the yield of RV from peanut stem and its potential radiosensitizing effects in prostate cancer (PCa) have not been well investigated. In this study, we characterized RV in peanut stem extract (PSE) for the first time and showed that both RV and PSE dose-dependently induced cell death in DOC-2/DAB2 interactive protein (DAB2IP)-deficient PCa cells with the radioresistant phenotype. Furthermore, the combination of radiation with either RV or PSE induced the death of radioresistant PCa cells through delayed repair of radiation-induced DNA double-strand break (DSB) and prolonged G2/M arrest, which induced apoptosis. The administration of RV and PSE effectively enhanced radiation therapy in the shDAB2IP PCa xenograft mouse model. These results demonstrate the promising synergistic effect of RV and PSE combined with radiation in the treatment of radioresistant PCa.

Measurement of in-plane elasticity of live cell layers using a pressure sensor embedded microfluidic device

In various physiological activities, cells experience stresses along their in-plane direction when facing substrate deformation. Capability of continuous monitoring elasticity of live cell layers during a period is highly desired to investigate cell property variation during various transformations under normal or disease states. This paper reports time-lapsed measurement of live cell layer in-plane elasticity using a pressure sensor embedded microfluidic device. The sensor converts pressure-induced deformation of a flexible membrane to electrical signals. When cells are cultured on top of the membrane, flexural rigidity of the composite membrane increases and further changes the output electrical signals. In the experiments, human embryonic lung fibroblast (MRC-5) cells are cultured and analyzed to estimate the in-plane elasticity. In addition, the cells are treated with a growth factor to simulate lung fibrosis to study the effects of cell transformation on the elasticity variation. For comparison, elasticity measurement on the cells by atomic force microscopy (AFM) is also performed. The experimental results confirm highly anisotropic configuration and material properties of cells. Furthermore, the in-plane elasticity can be monitored during the cell transformation after the growth factor stimulation. Consequently, the developed microfluidic device provides a powerful tool to study physical properties of cells for fundamental biophysics and biomedical researches.

Traffic-related air pollution increased the risk of Parkinson's disease in Taiwan: A nationwide study

BACKGROUND

Ambient air pollution has been associated with many health conditions, but little is known about its effects on neurodegenerative diseases, such as Parkinson's disease (PD). In this study, we investigated the influence of ambient air pollution on PD in a nationwide population-based case-control study in Taiwan.

METHODS

We identified 11,117 incident PD patients between 2007 and 2009 from the Taiwanese National Health Insurance Research Database and selected 44,468 age- and gender-matched population controls from the longitudinal health insurance database. The average ambient pollutant exposure concentrations from 1998 through the onset of PD were estimated using quantile-based Bayesian Maximum Entropy models. Basing from logistic regression models, we estimated the odds ratios (ORs) and 95% confidence intervals (CIs) of ambient pollutant exposures and PD risk.

RESULTS

We observed positive associations between NO_x, CO exposures, and PD. In multi-pollutant models, for NO_x and CO above the 75th percentile exposure compared with the lowest percentile, the ORs of PD were 1.37 (95% CI=1.23-1.52) and 1.17 (95% CI=1.07-1.27), respectively.

CONCLUSIONS

This study suggests that ambient air pollution exposure, especially from traffic-related pollutants such as NO_x and CO, increases PD risk in the Taiwanese population.

Helicobacter pylori Activates HMGB1 Expression and Recruits RAGE into Lipid Rafts to Promote Inflammation in Gastric Epithelial Cells

Helicobacter pylori infection is associated with several gastrointestinal disorders in the human population worldwide. High-mobility group box 1 (HMGB1), a ubiquitous nuclear protein, mediates various inflammation functions. The interaction between HMGB1 and receptor for advanced glycation end-products (RAGE) triggers nuclear factor (NF)-κB expression, which in turn stimulates the release of proinflammatory cytokines, such as interleukin (IL)-8, and enhances the inflammatory response. However, how H. pylori activates HMGB1 expression and mobilizes RAGE into cholesterol-rich microdomains in gastric epithelial cells to promote inflammation has not been explored. In this study, we found that HMGB1 and RAGE expression increased significantly in H. pylori-infected cells compared with -uninfected cells. Blocking HMGB1 by neutralizing antibody abrogated H. pylori-elicited RAGE, suggesting that RAGE expression follows HMGB1 production, and silenced RAGE-attenuated H. pylori-mediated NF-κB activation and IL-8 production. Furthermore, significantly more RAGE was present in detergent-resistant membranes extracted from H. pylori-infected cells than in those from -uninfected cells, indicating that H. pylori exploited cholesterol to induce the HMGB1 signaling pathway. These results indicate that HMGB1 plays a crucial role in H. pylori-induced inflammation in gastric epithelial cells, which may be valuable in developing treatments for H. pylori-associated diseases.

Lack of Genotype and Phenotype Correlation in a Rice T-DNA Tagged Line Is Likely Caused by Introgression in the Seed Source

Rice (Oryza sativa) is one of the most important crops in the world. Several rice insertional mutant libraries are publicly available for systematic analysis of gene functions. However, the tagging efficiency of these mutant resources-the relationship between genotype and phenotype-is very low. We used whole-genome sequencing to analyze a T-DNA-tagged transformant from the Taiwan Rice Insertional Mutants (TRIM) resource. The phenomics records for M0028590, one of the TRIM lines, revealed three phenotypes-wild type, large grains, and tillering dwarf-in the 12 T1 plants. Using the sequencing data for 7 plants from three generations of this specific line, we demonstrate that introgression from an indica rice variety might occur in one generation before the seed was used for callus generation and transformation of this line. In addition, the large-grain trait came from the GS3 gene of the introgressed region and the tillering dwarf phenotype came from a single nucleotide change in the D17 gene that occurred during the callus induction to regeneration of the transformant. As well, another regenerant showed completely heterozygous single-nucleotide polymorphisms across the whole genome. In addition to the known sequence changes such as T-DNA integration, single nucleotide polymorphism, insertion, deletion, chromosome rearrangement and doubling, spontaneous outcrossing occurred in the rice field may also explain some mutated traits in a tagged mutant population. Thus, the co-segregation of an integration event and the phenotype should be checked when using these mutant populations.