Nickel oxide nanoparticles (NiO NPs) are highly redox active nanoparticles. They can cause acute and chronic inflammation in rat lungs. Unlike the gut microbiome, the association between the lung microbiome’s role and pulmonary inflammatory response to inhaled nanoparticles remains largely unexplored. We aimed to explore the interaction between the lung microbiome and inflammatory responses in rats exposed to NiO NPs. Thirty female Wistar rats were randomly categorized into control and low- (50 cm²/rat), and high- (150 cm²/rat) dose NiO NPs exposure groups. NiO NPs were intratracheally instilled, and cytological, biochemical, proinflammatory cytokine, and lung microbiome analyses of bronchoalveolar lavage fluid were performed at 1 day and 4 weeks after instillation. NiO NPs caused a neutrophilic and lymphocytic inflammatory response in rat lung. We demonstrated that exposure to NiO NPs can alter the lung microbial composition in rats. In particular, we found that more Burkholderiales are present in the NiO NPs exposure groups than in the control group at 1 day after instillation. Dysbiosis in the lung microbiome is thought to be associated with acute lung inflammation. We also suggested that Burkholderiales may be a key biomarker associated with lung neutrophilic inflammation after NiO NPs exposure.

In our earlier paper dealing with dispersion retrieval from ultra-deep, reactive-ion-etched, slow-wave circuits on silicon substrates, it was proposed that splitting high-aspect-ratio circuits into multilevels enabled precise characterization in sub-terahertz frequency regime. This achievement prompted us to investigate beam-wave interaction through a vacuum-sealed integration with a 15-kV, 85-mA, thermionic, electron gun. Our experimental study demonstrates sub-terahertz, backward-wave amplification driven by an external oscillator. The measured output shows a frequency downshift, as well as power amplification, from beam loading even with low beam perveance. This offers a promising opportunity for the development of terahertz radiation sources, based on silicon technologies.

Engelhardtia chrysolepis Hance (ECH) is a perennial plant used in traditional medicine. A major active ingredient of ECH is astilbin (ASB), which has recently been shown to have neuroprotective effects as well as to affect catecholamine neurotransmissions in brain areas such as the prefrontal cortex. In this study, we investigated the effects of ECH and ASB on long-term memory in mice using a battery of behavioral tests. Acute ECH treatments dose-dependently facilitated nonspatial, but not spatial, memory. ECH treatments also upregulated expression of tyrosine hydroxylase, the enzyme mediating catecholamine synthesis, in neuroblastoma cell culture. Acute ASB treatments similarly improved nonspatial memory, whereas chronic ASB treatments improved both nonspatial and spatial memory. In accordance with such behavioral effects, the increased ratio of tissue concentrations of dopamine metabolites over dopamine in striatal regions was observed in mice with chronic ASB treatments. These results suggest that ECH and its active ingredient ASB may facilitate long-term memory by modulating catecholamine transmission.

Bronchoalveolar lavage fluid (BALF) analysis provides critical insights into pulmonary inflammation by identifying cellular components and inflammatory mediators in the airways and alveoli. However, variations in BALF collection protocols between laboratories limit cross-study comparison. Thus, optimal methodologies are necessary for future work on harmonization. In this study, we assessed critical parameters during BALF collection in rats by evaluating the number of lavages (1-5), the number of flushing repetitions (1 or 3 times), gentle lung massage, and the lavage volume adjusted for body weight. These procedures were evaluated under both non-inflamed, acutely inflamed, and chronically inflamed conditions induced by nanomaterials. Gentle lung massage, combined with three flushes (3FwM), resulted in the highest total cell recovery; however, it also increased variability and progressive cell depletion over multiple lavages. Conversely, performing a single flush without a massage (1FwoM) consistently produced stable and reproducible cytological and biochemical data across all inflammation models, thereby reducing experimental variability. In addition, both Dulbecco's phosphate-buffered saline (DPBS) and 0.9% saline were suitable lavage solutions, and DPBS supplemented with 10% fetal bovine serum effectively preserved BALF cell integrity for up to 1 week at 4°C. Automated cell counting offers superior reproducibility compared to manual counting, particularly under inflammatory conditions. Furthermore, we propose an equation to estimate the lavage volume applicable to the three rat strains. Thus, the proposed 1FwoM method represents a robust, standardized approach for collecting BALF, facilitating accurate comparisons, and enhancing regulatory inhalation toxicity assessments.