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Rehmannia glutinosa, a crucial medicinal plant native to China, is extensively cultivated across East Asia. We used high-throughput sequencing to identify viruses infecting R. glutinosa with mosaic, leaf yellowing, and necrotic symptoms. A novel Torradovirus, which we tentatively named “Rehmannia torradovirus virus” (ReTV), was identified. The complete sequences were obtained through reverse-transcription polymerase chain reaction (RT-PCR), 5′ and 3′ rapid amplification of cDNA ends, and Sanger sequencing. The amino acid sequence alignment between the ReTV-52 isolate and known Torradovirus species in the Pro-Pol and coat protein regions were 51.3–73.3% and 37.1–68.1%, respectively. Meanwhile, the amino acid sequence alignment between the ReTV-8 isolate and known Torradovirus species in the Pro-Pol and coat protein regions were 52.7–72.8% and 36.8–67.5%, respectively. The sequence analysis classified ten ReTV strains into two variants. The ReTV-52 genome has two RNA segments of 6939 and 4569 nucleotides, while that of ReTV-8 consists of two RNA segments containing 6889 and 4662 nucleotides. Sequence comparisons and phylogenetic analysis showed ReTV strains clustered within the Torradovirus, exhibiting the closet relation to the squash chlorotic leaf spot virus. The RT-PCR results showed a 100% ReTV detection rate in all 60 R. glutinosa samples. Therefore, ReTV should be classified as a novel Torradovirus species. ReTV is potentially dangerous to R. glutinosa, and necessitating monitoring this virus in the field.

Septic encephalopathy (SE) represents a severe inflammatory syndrome linked to elevated septic mortality rates, lacking specific therapeutic interventions, and often resulting in enduring neurological sequelae. The present investigation endeavors to elucidate the involvement of C-X-C Motif Chemokine Receptor 2 (CXCR2) in the pathogenesis of SE and to explore the potential of CXCR2 modulation as a therapeutic avenue for SE. Employing a murine SE model induced by lipopolysaccharide (LPS) administration, CXCR2 knockout mice and the CXCR2 inhibitor SB225002 were utilized to assess neutrophil recruitment, endothelial integrity, and transendothelial migration. Our findings substantiate that either CXCR2 deficiency or its inhibition curtails neutrophil recruitment without impacting their adhesion to cerebral endothelial cells. This phenomenon is contingent upon endothelial CXCR2 expression rather than CXCR2’s presence on neutrophils. Furthermore, the CXCR2 blockade preserves the integrity of tight junction protein ZO-1 and mitigates F-actin stress fiber formation in cerebral endothelial cells following septic challenge. Mechanistically, CXCL1-mediated CXCR2 activation triggers cerebral endothelial actin contraction via Rho signaling, thereby facilitating neutrophil transmigration in SE. These observations advocate for the potential therapeutic efficacy of CXCR2 inhibition in managing SE.

Rehmannia glutinosa is one of the most important medicinal plants in China and is affected by viral diseases. In this study, a new virus tentatively named Rehmannia Allexivirus virus (ReAV) was identified through high-throughput sequencing, reverse-transcription polymerase chain reaction (RT-PCR), and Sanger sequencing. The complete genome length was 7297 nt and it contained five open reading frames (ORFs) encoding replicase, triple gene block 1(TGB1), TGB2, TGB3, and coat protein (CP). The replicase and CP presented nucleotide homology ranges of 59.9–65.2% and 47.5–55.5% between the nine ReAV isolates and the other 12 species of the genus Allexivirus. In the nine isolates, ReAV-20 and ReAV-31 isolates showed breakpoints in the replicase and CP regions, respectively. The other isolates shared 87.2–96.5% nt with the whole genome nucleotide identity. The phylogenetic tree showed that seven ReAV isolates based on replicase, CP, and whole genome sequences were clustered in the same branch and were related to the genus Allexivirus. The ReAV detection rates for 60 R. glutinosa samples were 73.3–81.7% through RT-PCR using primers targeting the replicase or CP genes. These results demonstrate that ReAV is the dominant virus in R. glutinosa. This study provides important evidence for understanding viruses infecting R. glutinosa and for establishing efficient strategies to prevent viral spread.

Because of the significant environmental pollution produced by human activities, there is an ongoing need to develop transportable, simple, and reliable techniques for determining trace contaminants on the spot. This work reported a colorimetric detection method for aqueous Cr(VI) sensing by maleic acid-functionalized gold nanoparticles with high sensitivity and selectivity. The wine-red color of the probe solution can change to gray even in the presence of 1.0 µg L−1 of aqueous Cr(VI). Moreover, with the assistance of a smartphone installed with a commercially available color scan application software, its concentration of could be readily quantified on the spot without the help of UV-Vis spectrometer. The detection limit could reach as low as 0.1 µg L−1 with linear range from 0.2 to 2.0 µg L−1. Most importantly, the coefficient variation of the proposed smartphone-based method was equivalent to that of colorimetry, demonstrating the high accuracy of the proposed method for accurate detection of Cr(VI) in resource-constrained countries. Conclusively, with the help of the smartphone, this nanomaterials-based probe demonstrated the potential in the field of environment monitoring for on-site quantitative detection of any pollutants in resource-constrained countries.

Recently, biosensing based on weak coupling in plasmon-emitter hybrid nanostructures exhibits the merits of simplicity and high sensitivity, and attracts increasing attention as an emerging nano-sensor. In this study, we propose an innovative plasmon-regulated fluorescence resonance energy transfer (plasmon-regulated FRET) sensing strategy based on a plasmon-emitter hybrid nanostructure of gold nanorod-quantum dots (Au NR-QDs) by partially modifying QDs onto the surfaces of Au NRs. The Au NR-QDs showed good sensitivity and reversibility against refractive index change. We successfully employed the Au NR-QDs to fabricate nano-sensors for detecting a cancer biomarker of alpha fetoprotein with a limit of detection of 0.30 ng/mL, which displays that the sensitivity of the Au NR-QDs nano-sensor was effectively improved compared with the Au NRs based plasmonic sensing. Additionally, to demonstrate the universality of the plasmon-regulated FRET sensing strategy, another plasmon-emitter hybrid nano-sensor of Au nano-prism-quantum dots (Au NP-QDs) were constructed and applied for detecting a myocardial infarction biomarker of cardiac troponin I. It was first reported that the change of absorption spectra of plasmonic structure in a plasmon-emitter hybrid nanostructure was employed for analytes detection. The plasmon-regulated FRET sensing strategy described herein has potential utility to develop general sensing platforms for chemical and biological analysis.

Saliva contains important personal physiological information that is related to some diseases, and it is a valuable source of biochemical information that can be collected rapidly, frequently, and without stress. In this article, we reported a new and simple localized surface plasmon resonance (LSPR) substrate composed of polyaniline (PANI)-gold hybrid nanostructures as an optical sensor for monitoring the pH of saliva samples. The overall appearance and topography of the substrates, the composition, and the wettability of the LSPR surfaces were characterized by optical and scanning electron microscope (SEM) images, infrared spectra, and contact angles measurement, respectively. The PANI-gold hybrid substrate readily responded to the pH. The response time was very short, which was 3.5 s when the pH switched from 2 to 7, and 4.5 s from 7 to 2. The changes of visible-near-infrared (NIR) spectra of this sensor upon varying pH in solution showed that—for the absorption at given wavelengths of 665 nm and 785 nm—the sensitivities were 0.0299 a.u./pH (a.u. = arbitrary unit) with a linear range of pH = 5–8 and 0.0234 a.u./pH with linear range of pH = 2–8, respectively. By using this new sensor, the pH of a real saliva sample was monitored and was consistent with the parallel measurements with a standard laboratory method. The results suggest that this novel LSPR sensor shows great potential in the field of mobile healthcare and home medical devices, and could also be modified by different sensitive materials to detect various molecules or ions in the future.

Float glass installed with frame supports is broadly exploited in building construction. In a fire environment, the breakage of float glass significantly influences the dynamic development of the fire within the building space. The thermal rupture behavior of the frame-supported float glass subjected to thermal loading is carefully examined using a self-built experimental system. The designed system is aimed at capturing crucial behavioral parameters. The experimental study reveals that the main reason for the breakage of the frame-supported float glass is the temperature difference on the glass surface, with a critical temperature difference of approximately 65 °C. The crack starts at the edge of the glass surface where the temperature difference is maximum and then rapidly expands. By intersecting the cracks, a crack island is configured, which is not dislodged under the stress of the supporting frame and the surrounding glass. A thermomechanical and micro-geometric model of the frame-supported float glass is developed based on the PFC2D program to show further the micro-crack expansion pattern of the frame-supported float glass under thermal loading. This scrutiny provides theoretical guidance for installing and using frame-supported float glass in construction projects and identifying fire evidence.