Inter-laboratory evaluation studies for establishment of notified ELISA methods for allergic substances (peanuts)

Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter.     

A parallel Monte Carlo transport algorithm using a pseudo-random tree to guarantee reproducibility

We present a parallel Monte Carlo photon transport algorithm that insures the reproducibility of results. The important feature of this parallel implementation is the introduction of a pair of pseudo-random number generators. This pair of generators is structured in such a manner as to insure minimal correlation between the two sequences of pseudo-random numbers produced. We term this structure as a ‘pseudo-random tree’. Using this structure, we are able to reproduce results exactly in a asynchronous parallel processing environment. The algorithm tracks the history of photons as they interact with two carbon cylinders joined end to end. The algorithm was implemented on both a Denelcor HEP and a CRAY X-MP/48. We describe the algorithm and the pseudo-random tree structure and present speedup results of our implementation.     

Oxygen Content and Valence of Ru in RuSr2(Gd0.75Ce0.25)2Cu2O10−δ (Ru-1222) Magnetosuperconductor

The valence of Ru was analyzed for two RuSr₂(Gd_0.75Ce_0.25)₂Cu₂O_10– samples with different oxygen contents by Ru L _III-edge x-ray absorption near-edge structure (XANES) spectroscopy. For the sample as-synthesized in 1 atm O₂ the DC magnetization data measured in an applied field of 5 Oe showed a clear branching of the zero-field-cooled (ZFC) and field-cooled (FC) curves around 140 K, an up-turn for both around 100 K and a cusp at 85 K and a diamagnetic transition around 20 K in the ZFC part. A further confirmation for the superconductivity at 28 K was obtained from a resistance vs. temperature measurement. Annealing the as-synthesized sample in 100-atm O₂ atmosphere at 420°C increased the diamagnetic transition temperature from 20 K to 40 K. According to a thermogravimetric analysis, the oxygen content increased accordingly by ca. 0.1 oxygen atoms per formula unit. Quantitative analysis of the XANES spectra using Sr₂RuO₄ (Ru^IV) and Sr₂GdRuO₆ (Ru^V) as reference materials revealed a valence value of +4.74 and +4.81 for Ru in the as-synthesized and the 100-atm O₂-annealed sample, respectively. The obtained result suggests that the valence of Ru in Ru-1222 is affected by the change in oxygen content.     

Omeprazole Suppresses Oxaliplatin-Induced Peripheral Neuropathy in a Rodent Model and Clinical Database

(1) Background: Oxaliplatin is used as first-line chemotherapy not only for colorectal cancer but also for gastric and pancreatic cancers. However, it induces peripheral neuropathy with high frequency as an adverse event, and there is no effective preventive or therapeutic method. (2) Methods: The effects of omeprazole, a proton pump inhibitor (PPI), on oxaliplatin-induced peripheral neuropathy (OIPN) was investigated using an in vivo model and a real-world database. (3) Results: In a rat model, oxaliplatin (4 mg/kg, i.p., twice a week for 4 weeks) caused mechanical hypersensitivity accompanied by sciatic nerve axonal degeneration and myelin sheath disorder. Repeated injection of omeprazole (5–20 mg/kg, i.p., five times per week for 4 weeks) ameliorated these behavioral and pathological abnormalities. Moreover, omeprazole did not affect the tumor growth inhibition of oxaliplatin in tumor bearing mice. Furthermore, clinical database analysis of the Food and Drug Administration Adverse Event Reporting System (FAERS) suggests that the group using omeprazole has a lower reporting rate of peripheral neuropathy of oxaliplatin-treated patients than the group not using (3.06% vs. 6.48%, p < 0.001, reporting odds ratio 0.44, 95% confidence interval 0.32–0.61). (4) Conclusions: These results show the preventing effect of omeprazole on OIPN.     

Impacts of Glucose-Dependent Insulinotropic Polypeptide on Orthodontic Tooth Movement-Induced Bone Remodeling

Glucose-dependent insulinotropic polypeptide (GIP) exerts extra-pancreatic effects via the GIP receptor (GIPR). Herein, we investigated the effects of GIP on force-induced bone remodeling by orthodontic tooth movement using a closed-coil spring in GIPR-lacking mice (GIPRKO) and wild-type mice (WT). Orthodontic tooth movements were performed by attaching a 10-gf nickel titanium closed-coil spring between the maxillary incisors and the left first molar. Two weeks after orthodontic tooth movement, the distance of tooth movement by coil load was significantly increased in GIPRKO by 2.0-fold compared with that in the WT. The alveolar bone in the inter-root septum from the root bifurcation to the apex of M1 decreased in both the GIPRKO and WT following orthodontic tooth movement, which was significantly lower in the GIPRKO than in the WT. The GIPRKO exhibited a significantly decreased number of trabeculae and increased trabecular separation by orthodontic tooth movement compared with the corresponding changes in the WT. Histological analyses revealed a decreased number of steady-state osteoblasts in the GIPRKO. The orthodontic tooth movement induced bone remodeling, which was demonstrated by an increase in osteoblasts and osteoclasts around the forced tooth in the WT. The GIPRKO exhibited no increase in the number of osteoblasts; however, the number of osteoclasts on the coil-loaded side was significantly increased in the GIPRKO compared with in the WT. In conclusion, our results demonstrate the impacts of GIP on the dynamics of bone remodeling. We revealed that GIP exhibits the formation of osteoblasts and the suppression of osteoclasts in force-induced bone remodeling.     

Histidine-Rich Glycoprotein Suppresses the S100A8/A9-Mediated Organotropic Metastasis of Melanoma Cells

The dissection of the complex multistep process of metastasis exposes vulnerabilities that could be exploited to prevent metastasis. To search for possible factors that favor metastatic outgrowth, we have been focusing on secretory S100A8/A9. A heterodimer complex of the S100A8 and S100A9 proteins, S100A8/A9 functions as a strong chemoattractant, growth factor, and immune suppressor, both promoting the cancer milieu at the cancer-onset site and cultivating remote, premetastatic cancer sites. We previously reported that melanoma cells show lung-tropic metastasis owing to the abundant expression of S100A8/A9 in the lung. In the present study, we addressed the question of why melanoma cells are not metastasized into the brain at significant levels in mice despite the marked induction of S100A8/A9 in the brain. We discovered the presence of plasma histidine-rich glycoprotein (HRG), a brain-metastasis suppression factor against S100A8/A9. Using S100A8/A9 as an affinity ligand, we searched for and purified the binding plasma proteins of S100A8/A9 and identified HRG as the major protein on mass spectrometric analysis. HRG prevents the binding of S100A8/A9 to the B16-BL6 melanoma cell surface via the formation of the S100A8/A9 complex. HRG also inhibited the S100A8/A9-induced migration and invasion of A375 melanoma cells. When we knocked down HRG in mice bearing skin melanoma, metastasis to both the brain and lungs was significantly enhanced. The clinical examination of plasma S100A8/A9 and HRG levels showed that lung cancer patients with brain metastasis had higher S100A8/A9 and lower HRG levels than nonmetastatic patients. These results suggest that the plasma protein HRG strongly protects the brain and lungs from the threat of melanoma metastasis.     

Flexible Nanoarchitectonics for Biosensing and Physiological Monitoring Applications

Flexible and implantable electronics hold tremendous promises for advanced healthcare applications, especially for physiological neural recording and modulations. Key requirements in neural interfaces include miniature dimensions for spatial physiological mapping and low impedance for recognizing small biopotential signals. Herein, a bottom-up mesoporous formation technique and a top-down microlithography process are integrated to create flexible and low-impedance mesoporous gold (Au) electrodes for biosensing and bioimplant applications. The mesoporous architectures developed on a thin and soft polymeric substrate provide excellent mechanical flexibility and stable electrical characteristics capable of sustaining multiple bending cycles. The large surface areas formed within the mesoporous network allow for high current density transfer in standard electrolytes, highly suitable for biological sensing applications as demonstrated in glucose sensors with an excellent detection limit of 1.95 µm and high sensitivity of 6.1 mA cm⁻² µM⁻¹, which is approximately six times higher than that of benchmarking flat/non-porous films. The low impedance of less than 1 kΩ at 1 kHz in the as-synthesized mesoporous electrodes, along with their mechanical flexibility and durability, offer peripheral nerve recording functionalities that are successfully demonstrated in vivo. These features highlight the new possibilities of our novel flexible nanoarchitectonics for neuronal recording and modulation applications.     

Covalently Interlayer-Confined Organic–Inorganic Heterostructures for Aqueous Potassium Ion Supercapacitors (Small 4/2023)

Artificial assembly of organic–inorganic heterostructures for electrochemical energy storage at the molecular level is promising, but remains a great challenge. Here, a covalently interlayer-confined organic (polyaniline [PANI])–inorganic (MoS₂) hybrid with a dual charge-storage mechanism is developed for boosting the reaction kinetics of supercapacitors. Systematic characterizations reveal that PANI induces a partial phase transition from the 2H to 1T phases of MoS₂, expands the interlayer spacing of MoS₂, and increases the hydrophilicity. More in-depth insights from the synchrotron radiation-based X-ray technique illustrate that the covalent grafting of PANI to MoS₂ induces the formation of Mo N bonds and unsaturated Mo sites, leading to increased active sites. Theoretical analysis reveals that the covalent assembly facilitates cross-layer electron transfer and decreases the diffusion barrier of K⁺ ions, which favors reaction kinetics. The resultant hybrid material exhibits high specific capacitance and good rate capability. This design provides an effective strategy to develop organic–inorganic heterostructures for superior K-ion storage. The K-ion storage mechanism concerning the reversible insertion/extraction upon charge/discharge is revealed through ex situ X-ray photoelectron spectroscopy.