Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau.

Agricultural practices significantly contribute to greenhouse gas (GHG) emissions, necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production. Plastic film mulching is commonly used in the Loess Plateau region. Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity. Combining these techniques represents a novel agricultural approach in semi-arid areas. However, the impact of this integration on soil carbon storage (SOCS), carbon footprint (CF), and economic benefits has received limited research attention. Therefore, we conducted an eight-year study (2015-2022) in the semi-arid northwestern region to quantify the effects of four treatments [urea supplied without plastic film mulching (CK-U), slow-release fertilizer supplied without plastic film mulching (CK-S), urea supplied with plastic film mulching (PM-U), and slow-release fertilizer supplied with plastic film mulching (PM-S)] on soil fertility, economic and environmental benefits. The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions (≥71.97%). Compared to other treatments, PM-S increased average grain yield by 12.01%-37.89%, water use efficiency by 9.19%-23.33%, nitrogen accumulation by 27.07%-66.19%, and net return by 6.21%-29.57%. Furthermore, PM-S decreased CF by 12.87%-44.31% and CF per net return by 14.25%-41.16%. After eight years, PM-S increased SOCS (0-40 cm) by 2.46%, while PM-U decreased it by 7.09%. These findings highlight the positive effects of PM-S on surface soil fertility, economic gains, and environmental benefits in spring maize production on the Loess Plateau, underscoring its potential for widespread adoption and application.

Antimicrobial blue light inactivation of Pseudomonas aeruginosa: Unraveling the multifaceted impact of wavelength, growth stage, and medium composition.

Pseudomonas aeruginosa, a notable pathogen frequently associated with hospital-acquired infections, displays diverse intrinsic and acquired antibiotic resistance mechanisms, posing a significant challenge in infection management. Antimicrobial blue light (aBL) has been demonstrated as a potential alternative for treating P. aeruginosa infections. In this study, we investigated the impact of blue light wavelength, bacterial growth stage, and growth medium composition on the efficacy of aBL. First, we compared the efficacy of light wavelengths 405 nm, 415 nm, and 470 nm in killing three multidrug resistant clinical strains of P. aeruginosa. The findings indicated considerably higher antibacterial efficacy for 405 nm and 415 nm wavelength compared to 470 nm. We then evaluated the impact of the bacterial growth stage on the efficacy of 405 nm light in killing P. aeruginosa using a reference strain PAO1 in exponential, transitional, or stationary phase. We found that bacteria in the exponential phase were the most susceptible to aBL, followed by the transitional phase, while those in the stationary phase exhibited the highest tolerance. Additionally, we quantified the production of reactive oxygen species (ROS) in bacteria using the 2',7'-dichlorofluorescein diacetate (DCFH-DA) probe and flow cytometry, and observed a positive correlation between aBL efficacy and ROS production. Finally, we determined the influence of growth medium on aBL efficacy. PAO1 was cultivated in brain heart infusion (BHI), Luria-Bertani (LB) broth or Casamino acids (CAA) medium, before being irradiated with aBL at 405 nm. The CAA-grown bacteria exhibited the highest sensitivity to aBL, followed by those grown in LB broth, and the BHI-grown bacteria demonstrated the lowest sensitivity. By incorporating FeCl3, MnCl2, ZnCl2, or the iron chelator 2,2'-bipyridine (BIP) into specific media, we discovered that aBL efficacy was affected by the iron levels in culture media.

Cancer therapy resistance mediated by cancer-associated fibroblast-derived extracellular vesicles: biological mechanisms to clinical significance and implications.

Cancer-associated fibroblasts (CAFs) are a diverse stromal cell population within the tumour microenvironment, where they play fundamental roles in cancer progression and patient prognosis. Multiple lines of evidence have identified that CAFs are critically involved in shaping the structure and function of the tumour microenvironment with numerous functions in regulating tumour behaviours, such as metastasis, invasion, and epithelial-mesenchymal transition (EMT). CAFs can interact extensively with cancer cells by producing extracellular vesicles (EVs), multiple secreted factors, and metabolites. Notably, CAF-derived EVs have been identified as critical mediators of cancer therapy resistance, and constitute novel therapy targets and biomarkers in cancer management. This review aimed to summarize the biological roles and detailed molecular mechanisms of CAF-derived EVs in mediating cancer resistance to chemotherapy, targeted therapy agents, radiotherapy, and immunotherapy. We also discussed the therapeutic potential of CAF-derived EVs as novel targets and clinical biomarkers in cancer clinical management, thereby providing a novel therapeutic strategy for enhancing cancer therapy efficacy and improving patient prognosis.

Rnai-based functional analysis of bursicon genes related to cuticle pigmentation in a ladybird beetle.

In arthropods, the binding of a bursicon (encoded by burs and pburs) heterodimer or homodimer to a leucine-rich repeat-containing G protein coupled receptor LGR2 (encoded by rk) can activate many physiological processes, especially cuticle pigmentation during insect ecdysis. In the current paper, we intended to ascertain whether bursicon signaling mediates body coloration in the 28-spotted larger potato ladybird, Henosepilachna vigintioctomaculata, and if so, by which way bursicon signal governs the pigmentation. The high expression of Hvburs, Hvpburs and Hvrk occurred in the young larvae, pupae and adults, especially in the head and ventral nerve cord. RNA interference (RNAi) aided knockdown of Hvburs, Hvpburs or Hvrk in the prepupae caused similar phenotypic defects. The pigmentation of the resultant adults was affected, with significantly reduced dark areas on the sternums. Moreover, the accumulated mRNA levels of two sclerotin biosynthesis genes, aspartate 1-decarboxylase gene Hvadc and N-ß-alanyldopamine synthase gene Hvebony, were significantly increased in the Hvburs, Hvpburs or Hvrk RNAi beetles. Furthermore, depletion of either Hvadc or Hvebony could completely rescue the impaired coloration on the sternums of Hvpburs RNAi adult. Our results supported that bursicon heterodimer-mediated signal regulate cuticle pigmentation. The bursicon signaling may tune the ratio of melanins (dark/black, brown) to sclerotins (light yellow, colorless) exerting its regulative role in the pigmentation of H. vigintioctomaculata sternums.

Genetic diversity and population structure of Plenodomus biglobosus on flixweed (Descurainia sophia) in northwestern China.

Plenodomus biglobosus (Pb), a causal agent of blackleg of rapeseed, is composed of several subspecies, including 'australensis' (Pba), 'brassicae' (Pbb) and 'canadensis' (Pbc). Besides rapeseed, Pb can infect many wild cruciferous plants (WCPs), such as flixweed (Descurainia sophia) and pennycress (Thlaspi arvense), which may become the infection source for blackleg of rapeseed. However, Pb on WCPs has not been well investigated in China. This study identified the blackleg fungi on two WCPs in Sayram Lake and Zhaosu County in Xinjiang of China: flixweed (15 isolates) and pennycress (1 isolate) as well as on rapeseed (971 isolates). They belonged to Pba (11), Pbb (18) and Pbc (958). Pba occurred on flixweed (10) and pennycress (1) only in Sayram Lake, whereas Pbb and Pbc occurred on flixweed (1 and 4 isolates, respectively) and rapeseed (17 and 954 isolates, respectively) in Zhaosu County. Then, virulence of 16 isolates from flixweed and pennycress was determined on rapeseed. Their genomes were sequenced and used to identify the mating-type idiomorphs and to analyze population genetic structure. Results showed that all of the 16 isolates were virulent to rapeseed. Only MAT1-1 was detected in 11 Pba isolates, implying that Pba may lack sexual reproduction. The 16 isolates from two WCPs were divided into four genetic groups: Group I for Pbc (4 isolates), Group II for Pbb (1 isolate), and Group III (3 isolates) and IV (8 isolates) for Pba. The findings about the single mating-type in Pba and its limited geographic distribution provided a case showing the importance of sexual reproduction in epidemics of Pb. To the best of our knowledge, this is the first report of Pba, Pbb and Pbc on flixweed, and Pba on pennycress in China.

Integrated monitoring and prediction of thermal discharge from nuclear power plants using satellite, UAV, and numerical simulation.

Global nuclear power is surging ahead in its quest for global carbon neutrality, eyeing an anticipated installed capacity of 436 GW for coastal nuclear power plants by 2040. As these plants operate, they emit substantial amounts of warm water into the ocean, known as thermal discharge, to regulate the temperature of their nuclear reactors. This discharge has the potential to elevate the temperature of the surrounding seawater, potentially influencing the marine ecosystem in the discharge vicinity. Therefore, our study area is on the Qinshan and Jinqimen Nuclear Power Plants in China, employing a blend of Landsat 8/9, and unmanned aerial vehicle (UAV) imagery to gather sea surface temperature (SST) data. In situ measurements validate the temperature data procured through remote sensing. Leveraging these SST observations alongside hydrodynamic and meteorological data from field measurements, we input them into the MIKE 3 model to prognosticate the three-dimensional (3D) spatial distribution and temperature elevation resulting from thermal discharge. The findings reveal that (1) satellite remote sensing can instantly acquire the horizontal distribution of thermal discharge, but with a spatial resolution much lower than that of UAV. The spatial resolution of UAV is higher, but the imaging efficiency of UAV is only 1/40,000 of that of satellite remote sensing. (2) Numerical simulation models can predict the 3D spatial distribution of thermal discharge. Although UAV and satellite remote sensing cannot directly obtain the 3D spatial distribution of thermal discharge, using remotely sensed SST as the temperature field input for the MIKE 3 model can reduce the quantity of measured temperature data and lower the cost of numerical simulation. (3) In the process of monitoring and predicting the thermal discharge of nuclear power plants, achieving an effective balance between monitoring accuracy and cost can be realized by comprehensively considering the advantages and costs of satellite, UAV, and numerical simulation technologies.

Straw returning and nitrogen reduction: Strategies for sustainable maize production in the dryland.

Implementing continue straw returning practices and optimizing nitrogen application can mitigate nitrogen losses and enhance nitrogen use efficiency (NUE) in dryland. 15N-labeled technique offers a robust approach for tracking fertilizer nitrogen fate and assessing nitrogen use efficiency. Based on the continue (>6 yr) experiment, we conducted a two-year experiment (2020 and 2021) to evaluate the effects of straw returning and nitrogen management under plastic film mulching on 15N recovery rates, N2O emissions and maize yield with three treatments: no straw returning with 225 kg N·ha-1 under plastic film mulching (RP-N225), straw returning with 225 kg N·ha-1 under plastic film mulching (RPS-N225), and straw returning with 20% nitrogen reduction (180 kg N·ha-1) under plastic film mulching (RPS-N180). After six years, both continue straw returning with plastic film mulching increased uptake of fertilizer nitrogen, had higher 15N recovery rates than RP-N225, leading to increased 15N accumulation in grain and aboveground biomass, ultimately enhancing yield. The RPS-N225 treatment exhibited the highest spring maize yield and nitrogen harvest index. The RPS-N180 treatment significantly increased maize yield more than RP-N225 and had the highest NUE, partial factor productivity of nitrogen fertilizer, and nitrogen uptake efficiency, with improvements ranging from 1.7 to 2.4%, 19.3-29.6%, and 17.3-27.5%, respectively, compared to the other treatments. Moreover, RPS-N225 resulted in significantly higher cumulative N2O emissions and yield-scaled N2O emissions than the other treatments, whereas the RPS-N180 treatment significantly decreased yield-scaled N2O emissions compared to RP-N225. Hence, combining continue straw returning with appropriate nitrogen reduction can effectively increase maize yield and yield-scaled N2O emissions. By offering insights into optimizing nitrogen fertilizer management after continue maize straw return, this study is contributed to widespread adoption of straw return practices and sustainable agricultural development in semi-arid areas.

Monitoring of temperature rise in global nuclear power plant thermal discharge from 2013 to 2022.

The development of nuclear power plants is progressing rapidly worldwide. However, there is currently a lack of dynamic monitoring of the thermal discharge temperature rise from these plants, making it unclear to governments where their nuclear power thermal discharges stand globally. We hypothesize that between 2013 and 2022, there are significant temporal and spatial differences in the thermal discharge temperature rise from nuclear power plants globally. Temporal differences are expected to reflect a country's nuclear power installed capacity and thermal discharge treatment capabilities, while spatial differences are related to the type of water bodies where nuclear power plants are located. To test these hypotheses, we utilized Landsat data to get the distribution range of thermal discharge and temperature rise levels ranging from 1 °C to 4 °C, and compared the temporal and spatial characteristics of temperature rise in different countries. The results indicate that: (1) Currently, China, the United States, and Canada rank among the top three globally in terms of the area experiencing temperature rise due to thermal discharge, which correlates with the total installed capacity of nuclear power in these countries. (2) Countries such as Russia, Finland, and Mexico exhibit larger areas with a 4 °C temperature rise level per unit installed capacity, with their thermal rise area per unit installed capacity (TRAUIC) exceeding the global average by more than 1.5 times. (3) The spatial dispersion trends of thermal discharges from nuclear power plants vary across different types of water bodies. For nuclear power plants located in bays, thermal discharges primarily disperse along the coast, while in open sea and lakes, thermal discharges tend to spread in a fan-shaped pattern. The findings of this study are crucial for understanding the efficiency of thermal discharge from nuclear power plants across different countries globally, assessing potential environmental risks during the operation of these plants, and promoting the safe and orderly development of nuclear power plants worldwide.

Evaluation of vaccine candidates against Rhodococcus equi in BALB/c mice infection model: cellular and humoral immune responses.

Rhodococcus equi (R. equi) is a zoonotic opportunistic pathogen that mainly causes fatal lung and extrapulmonary abscesses in foals and immunocompromised individuals. To date, no commercial vaccine against R. equi exists. We previously screened all potential vaccine candidates from the complete genome of R. equi using a reverse vaccinology approach. Five of these candidates, namely ABC transporter substrate-binding protein (ABC transporter), penicillin-binding protein 2 (PBD2), NlpC/P60 family protein (NlpC/P60), esterase family protein (Esterase), and M23 family metallopeptidase (M23) were selected for the evaluation of immunogenicity and immunoprotective effects in BALB/c mice model challenged with R. equi. The results showed that all five vaccine candidate-immunized mice experienced a significant increase in spleen antigen-specific IFN-γ- and TNF-α-positive CD4 + and CD8 + T lymphocytes and generated robust Th1- and Th2-type immune responses and antibody responses. Two weeks after the R. equi challenge, immunization with the five vaccine candidates reduced the bacterial load in the lungs and improved the pathological damage to the lungs and livers compared with those in the control group. NlpC/P60, Esterase, and M23 were more effective than the ABC transporter and PBD2 in inducing protective immunity against R. equi challenge in mice. In addition, these vaccine candidates have the potential to induce T lymphocyte memory immune responses in mice. In summary, these antigens are effective candidates for the development of protective vaccines against R. equi. The R. equi antigen library has been expanded and provides new ideas for the development of multivalent vaccines.

Comparative Transcriptome Analysis of Henosepilachna vigintioctomaculata Reveals Critical Pathways during Development.

Henosepilachna vigintioctomaculata is distributed in several Asian countries. The larvae and adults often cause substantial economic losses to Solanaceae crops such as potato, tomato, eggplant, and Chinese boxthorn. Even though a chromosome-level genome has been documented, the expression profiles of genes involved in development are not determined. In this study, we constructed embryonic, larval, pupal, and adult transcriptomes, generated a comprehensive RNA-sequencing dataset including ~52 Gb of clean data, and identified 602,773,686 cleaned reads and 33,269 unigenes. A total of 18,192 unigenes were successfully annotated against NCBI nonredundant protein sequences, Swissprot, Eukaryotic Orthologous Groups, Gene Ontology (GO), or Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. There were 3580, 2040, 5160, 2496, 3008, and 3895 differentially expressed genes (DEGs) between adult/egg, egg/larval, larval/pupal, adult/pupal, egg/pupal, and adult/larval samples, respectively. GO and KEGG analyses of the DEGs highlighted several critical pathways associated with specific developing stages. This is the first comprehensive transcriptomic dataset encompassing all developmental stages in H. vigintioctomaculata. Our data may facilitate the exploitation of gene targets for pest control and can serve as a valuable gene resource for future molecular investigations.

Enhanced antibiofilm potential of low-intensity pulsed ultrasound combined with 0.35% povidone-iodine in a rat model of periprosthetic joint infection.

Aims: Although low-intensity pulsed ultrasound (LIPUS) combined with disinfectants has been shown to effectively eliminate portions of biofilm in vitro, its efficacy in vivo remains uncertain. Our objective was to assess the antibiofilm potential and safety of LIPUS combined with 0.35% povidone-iodine (PI) in a rat debridement, antibiotics, and implant retention (DAIR) model of periprosthetic joint infection (PJI). Methods: A total of 56 male Sprague-Dawley rats were established in acute PJI models by intra-articular injection of bacteria. The rats were divided into four groups: a Control group, a 0.35% PI group, a LIPUS and saline group, and a LIPUS and 0.35% PI group. All rats underwent DAIR, except for Control, which underwent a sham procedure. General status, serum biochemical markers, weightbearing analysis, radiographs, micro-CT analysis, scanning electron microscopy of the prostheses, microbiological analysis, macroscope, and histopathology evaluation were performed 14 days after DAIR. Results: The group with LIPUS and 0.35% PI exhibited decreased levels of serum biochemical markers, improved weightbearing scores, reduced reactive bone changes, absence of viable bacteria, and decreased inflammation compared to the Control group. Despite the greater antibiofilm activity observed in the PI group compared to the LIPUS and saline group, none of the monotherapies were successful in preventing reactive bone changes or eliminating the infection. Conclusion: In the rat model of PJI treated with DAIR, LIPUS combined with 0.35% PI demonstrated stronger antibiofilm potential than monotherapy, without impairing any local soft-tissue.

Association between serum phosphate, magnesium, calcium and aortic valve sclerosis: a propensity score-matched case-control study.

OBJECTIVES: Aortic valve sclerosis has been proposed to signify greater cardiovascular risk; the correlation between serum trace elements and aortic valve sclerosis has been reported. Therefore, an in-depth exploration of the risk factors for aortic valve sclerosis and early intervention may reduce the risk of cardiovascular disease. METHODS: In this study, Patients with aortic valve sclerosis and non-aortic valve sclerosis who underwent echocardiographic diagnosis in the People's Hospital of Xinjiang Uygur Autonomous Region during the period from 2019 to 2021 were selected for this study. The correlation between aortic valve sclerosis and serum phosphorus, calcium, and magnesium levels was explored using the propensity score matching technique by pairing the two groups of patients 1:1. RESULTS: A total of 1,533 non-aortic valve sclerosis and 1,533 aortic valve sclerosis patients were included. Logistic regression analysis showed that serum magnesium [OR: 0.346; 95%CI: 0.227, 0.528] and serum calcium [OR: 7.022; 95%CI: 4.755, 10.369] were influential factors. Patients with low, intermediate, and high serum magnesium levels had a significantly lower risk of aortic valve sclerosis compared to patients with very low micronutrient levels (p < 0.05). Comparatively, patients with low or high serum calcium levels had an elevated risk of aortic valve sclerosis (p < 0.05). CONCLUSION: Serum magnesium may have a protective role against aortic valve sclerosis, while both low and high levels of serum calcium could be risk factor for the condition. These serum micronutrients may be indications of cardiovascular disease risk prediction or prevention, and more research is required.

Behavioral events and functional analysis of bursicon signal during adult eclosion in the 28-spotted larger potato ladybird.

To accommodate growth, insects must periodically shed their exoskeletons. In Manduca sexta, Drosophila melanogaster and Tribolium castaneum, Bursicon (Burs)/ Partner of bursicon (Pburs)-LGR2 signal is an indispensable component for the proper execution of ecdysis behavior during adult eclosion. Nevertheless, the behavioral events and the roles of bursicon signaling in other insects deserve further exploration. In the current paper, we found that the pupal-adult ecdysis in Henosepilachna vigintioctomaculata could be divided into three distinct stages, preecdysis, ecdysis and postecdysis. Preecdysis behavioral sequences included abdomen twitches, dorsal-ventral contractions and air filling that function to loosen the old cuticle. Ecdysis events began with anterior-posterior contractions that gradually split the old integument along the dorsal body midline, followed by freeing of legs and mouthparts, and culminated in detachment from pupal cuticle. Postecdysis behavioral processes contained three actions: perch selection and stretching of elytra and hindwings. RNA interference for HvBurs, HvPburs or Hvrk (encoding LGR2) strongly impaired wing expansion actions, and slightly influenced preecdysis and ecdysis behaviors. The RNAi beetles failed to extend their elytra and hindwings. In addition, injected with dsrk also caused kinked femurs and tibia. Our findings establish that bursicon pathway is involved in regulation of adult eclosion behavior, especially wing expansion motor programs. Given that wings facilitate food foraging, courtship, predator avoidance, dispersal and migration, our results provide a potential target for controlling H. vigintioctomaculata.

CircRNA SEC24A promotes osteoarthritis through miR-107-5p/CASP3 axis.

Background: Osteoarthritis (OA) is the most frequently diagnosed chronic joint disease. CircSEC24A is significantly elevated in OA chondrocytes upon IL-1ß stimulation. However, its biological function in OA is still not fully understood. Methods: The circRNAs-miRNA-mRNA network was predicted by bioinformatics analysis. An in vitro OA chondrocytes model was established by IL-1ß stimulation. The expression of circSEC24A, miR-107-5p, CASP3, apoptosis-related molecules and extracellular matrix (ECM) components were detected by Western blot and qRT-PCR. MTT assay and Annexin V/PI staining were employed to monitor cell viability and apoptosis, respectively. The interaction between circSEC24A and miR-107-5p, as well as the binding between miR-107-5p and CASP3 3' UTR were detected by luciferase reporter and RIP assays. Cytokine secretion was monitored by ELISA assay. The role of circSEC24A was also explored in anterior cruciate ligament transection (ACLT) rat models. Results: CircSEC24A and CASP3 were increased, but miR-107-5p was decreased in rat OA cartilage tissues and OA chondrocytes. CircSEC24A acted as a sponge of miR-107-5p. Knockdown of circSEC24A promoted chondrocyte proliferation, but suppressed chondrocyte apoptosis, ECM degradation and inflammation via sponging miR-107-5p. CASP3 was identified as a miR-107-5p target gene. MiR-107-5p mimics protected against OA progression via targeting CASP3. Silencing of circSEC24A alleviated OA progression in ACLT model. Conclusion: CircSEC24A promotes OA progression through miR-107-5p/CASP3 axis.

Recent advances in C(sp3)-N bond formation via metallaphoto-redox catalysis.

The C(sp3)-N bond is ubiquitous in natural products, pharmaceuticals, biologically active molecules and functional materials. Consequently, the development of practical and efficient methods for C(sp3)-N bond formation has attracted more and more attention. Compared to the conventional ionic pathway-based thermal methods, photochemical processes that proceed through radical mechanisms by merging photoredox and transition-metal catalyses have emerged as powerful and alternative tools for C(sp3)-N bond formation. In this review, recent advances in the burgeoning field of C(sp3)-N bond formation via metallaphotoredox catalysis have been highlighted. The contents of this review are categorized according to the transition metals used (copper, nickel, cobalt, palladium, and iron) together with photocatalysis. Emphasis is placed on methodology achievements and mechanistic insight, aiming to inspire chemists to invent more efficient radical-involved C(sp3)-N bond-forming reactions.

Morphological and life-history trait plasticity of two Daphnia species induced by fish kairomones.

Daphnia can avoid predation by sensing fish kairomones and producing inducible defenses by altering the phenotype. In this study, the results showed that the morphological and life-history strategies of two Daphnia species (Daphnia pulex and Daphnia sinensis) exposed to Aristichthys nobilis kairomones. In the presence of fish kairomones, the two Daphnia species exhibited significantly smaller body length at maturity, smaller body length of offspring at the 10th instar, and longer relative tail spine of offspring. Nevertheless, other morphological and life-history traits of the two Daphnia species differed. D. pulex showed a significantly longer relative tail spine length and earlier age at maturity after exposure to fish kairomones. The total offspring number of D. sinensis exposed to fish kairomones was significantly higher than that of the control group, whereas that of D. pulex was significantly lower. These results suggest that the two Daphnia species have different inducible defense strategies (e.g., morphological and life-history traits) during prolonged exposure to A. nobilis kairomones, and their offspring also develop morphological defenses to avoid predation. It will provide reference for further exploring the adaptive evolution of Daphnia morphology and life-history traits in the presence of planktivorous fish.

Full-angle single-shot quantitative phase imaging based on Kramers-Kronig relations.

As a non-interference and non-iterative method, annular-illumination quantitative phase imaging based on Kramers-Kronig relations (AIKK) can realize phase measurement with full-angle resolution enhancement under multiple exposures. In order to completely record the object spectrum with a single shot, we proposed a colorful complementary illumination method in the recording process. The angle of this illumination mode is not symmetrical with each other, so the spectrum between the three channels can complement each other to avoid spectrum loss caused by spectrum conjugation. Meanwhile, the three spectral segments of full-angle information spectrum respectively carried by three wavelengths can be recorded. Additionally, the numerical filter is applied to correct the overlapped spectrum in the reconstruction process. Simulation and experimental results show that this method can achieve high spatiotemporal resolution quantitative phase measurement.

Negatively charged nanodiscs for the reduction of toxicity and enhanced efficacy of polymyxin B against Acinetobacter baumannii sepsis.

The treatment of sepsis caused by multidrug-resistant (MDR) Gram-negative bacterial infections remains challenging. With these pathogens exhibiting resistance to carbapenems and new generation cephalosporins, the traditional antibiotic polymyxin B (PMB) has reemerged as a critical treatment option. However, its severe neurotoxicity and nephrotoxicity greatly limit the clinical application. Therefore, we designed negatively charged high-density lipoprotein (HDL) mimicking nanodiscs as a PMB delivery system, which can simultaneously reduce toxicity and enhance drug efficacy. The negative charge prevented the PMB release in physiological conditions and binding to cell membranes, significantly reducing toxicity in mammalian cells and mice. Notably, nanodisc-PMB exhibits superior efficacy than free PMB in sepsis induced by carbapenem-resistant Acinetobacter baumannii (CRAB) strains. Nanodisc-PMB shows promise as a treatment for carbapenem-resistant Gram-negative bacterial sepsis, especially caused by Acinetobacter baumannii, and the nanodiscs could be repurposed for other toxic antibiotics as an innovative delivery system. STATEMENT OF SIGNIFICANCE: Multidrug-resistant Gram-negative bacteria, notably carbapenem-resistant Acinetobacter baumannii, currently pose a substantial challenge due to the scarcity of effective treatments, rendering Polymyxins a last-resort antibiotic option. However, their therapeutic application is significantly limited by severe neurotoxic and nephrotoxic side effects. Prevailing polymyxin delivery systems focus on either reducing toxicity or enhancing bioavailability yet fail to simultaneously achieve both. In this scenario, we have developed a distinctive HDL-mimicking nanodisc for polymyxin B, which not only significantly reduces toxicity but also improves efficacy against Gram-negative bacteria, especially in sepsis caused by CRAB. This research offers an innovative drug delivery system for polymyxin B. Such advancement could notably improve the therapeutic landscape and make a significant contribution to the arsenal against these notorious pathogens.