-
Journal of Hazardous Materials Jun 2024A redox co-precipitation method was employed to synthesize CeMn homogeneous solid solutions, utilizing various alcohols as activating agents. Ethanol effectively...
A redox co-precipitation method was employed to synthesize CeMn homogeneous solid solutions, utilizing various alcohols as activating agents. Ethanol effectively orchestrated the precipitation of CeO and MnO, promoting their co-growth. As a result, the CeMn-EA achieved 90 % toluene conversion at 218 ℃ (T =218 ℃) with a weight hourly space velocity (WHSV) of 48000 ml/(g·h). It also demonstrated high adaptability to increased WHSV, suggesting its potential for industrial-scale applications. The uniform dispersion of Ce and Mn accelerated the coupling between Ce/Ce and Mn/Mn, engineering numerous oxygen vacancies, which enhanced the activation of gas-phase oxygen and the mobility of lattice oxygen. In situ DRIFTS confirmed that toluene oxidation accommodated both Langmuir-Hinshelwood (L-H) and Mars-van Krevelen (MvK) mechanisms, with benzoate identified as a pivotal intermediate. Enhanced oxygen mobility facilitated the cleavage of the benzene ring, which was the rate-determining step. Additionally, the introduction of HO significantly enhanced the dissociation and adsorption of toluene and facilitated the activation of gas-phase oxygen. At higher temperatures, HO could further activate lattice oxygen engaging in toluene oxidation. ENVIRONMENTAL IMPLICATION: Volatile organic compounds (VOCs) have emerged as major air pollutants due to the changes in air pollution patterns. They can act as precursors to near-surface ozone and haze. Toluene, a typical VOC, is primarily released from anthropogenic sources and poses significant risks to human health and the environment. Ce-based catalysts have been demonstrated efficiency in toluene oxidation due to their excellent oxygen storage and release properties. This study synthesized CeMn homogeneous solid solutions utilizing various alcohols as activating agents, which possessed abundant oxygen vacancies and optimum oxygen activation capacity to oxidize toluene in time.
PubMed: 38954854
DOI: 10.1016/j.jhazmat.2024.135051 -
Environmental Geochemistry and Health Jul 2024Recently, the hazardous effects of antibiotic micropollutants on the environment and human health have become a major concern. To address this challenge,...
Recently, the hazardous effects of antibiotic micropollutants on the environment and human health have become a major concern. To address this challenge, semiconductor-based photocatalysis has emerged as a promising solution for environmental remediation. Our study has developed BiWO/g-CN (BWCN) photocatalyst with unique characteristics such as reactive surface sites, enhanced charge transfer efficiency, and accelerated separation of photogenerated electron-hole pairs. BWCN was utilized for the oxidation of tetracycline antibiotic (TCA) in different water sources. It displayed remarkable TCA removal efficiencies in the following order: surface water (99.8%) > sewage water (88.2%) > hospital water (80.7%). Further, reusability tests demonstrated sustained performance of BWCN after three cycles with removal efficiencies of 87.3, 71.2 and 65.9% in surface water, sewage, and hospital water, respectively. A proposed photocatalytic mechanism was delineated, focusing on the interaction between reactive radicals and TCA molecules. Besides, the transformation products generated during the photodegradation of TCA were determined, along with the discussion on the potential risk assessment of antibiotic pollutants. This study introduces an approach for utilizing BWCN photocatalyst, with promising applications in the treatment of TCA from various wastewater sources.
Topics: Water Pollutants, Chemical; Anti-Bacterial Agents; Oxidation-Reduction; Tetracycline; Catalysis; Wastewater; Bismuth; Graphite; Nitrogen Compounds; Tungsten Compounds; Photolysis; Water Purification; Sewage
PubMed: 38954124
DOI: 10.1007/s10653-024-02050-y -
Journal of Plant Research Jul 2024We have performed a lab-based hypergravity cultivation experiment using a centrifuge equipped with a lighting system and examined long-term effects of hypergravity on...
We have performed a lab-based hypergravity cultivation experiment using a centrifuge equipped with a lighting system and examined long-term effects of hypergravity on the development of the main axis of the Arabidopsis (Arabidopsis thaliana (L.) Heynh.) primary inflorescence, which comprises the rachis and peduncle, collectively referred to as the main stem for simplicity. Plants grown under 1 × g (gravitational acceleration on Earth) conditions for 20-23 days and having the first visible flower bud were exposed to hypergravity at 8 × g for 10 days. We analyzed the effect of prolonged hypergravity conditions on growth, lignin deposition, and tissue anatomy of the main stem. As a result, the length of the main stem decreased and cross-sectional area, dry mass per unit length, cell number, and lignin content of the main stem significantly increased under hypergravity. Lignin content in the rosette leaves also increased when they were exposed to hypergravity during their development. Except for interfascicular fibers, cross-sectional areas of the tissues composing the internode significantly increased under hypergravity in most types of the tissues in the basal part than the apical part of the main stem, indicating that the effect of hypergravity is more pronounced in the basal part than the apical part. The number of cells in the fascicular cambium and xylem significantly increased under hypergravity both in the apical and basal internodes of the main stem, indicating a possibility that hypergravity stimulates procambium activity to produce xylem element more than phloem element. The main stem was suggested to be strengthened through changes in its morphological characteristics as well as lignin deposition under prolonged hypergravity conditions.
PubMed: 38954119
DOI: 10.1007/s10265-024-01556-x -
Lab on a Chip Jul 2024The recapitulation of tumor microenvironment is of great interest to preclinical screening of drugs. Compared with culture of cell lines, tumor organ slices can better...
The recapitulation of tumor microenvironment is of great interest to preclinical screening of drugs. Compared with culture of cell lines, tumor organ slices can better preserve the complex tumor architecture and phenotypic activity of native cells, but are limited by their exposure to fluid shear and gradual degradation under perfusion culture. Here, we established a decellularized liver matrix (DLM)-GelMA "sandwich" structure and a perfusion-based microfluidic platform to support long-term culture of tumor slices with excellent structural integrity and cell viability over 7 days. The DLM-GelMA was able to secrete cytokines and growth factors while providing shear protection to the tumor slice the sandwich structure, leading to the preservation of the tumor microenvironment where immune cells (CD3, CD8, CD68), tumor-associated fibroblasts (α-SMA), and extracellular matrix components (collagen I, fibronectin) were well maintained. Furthermore, this chip presented anti-tumor efficacy at cisplatin (20 μM) on tumor patients, demonstrating our platform's efficacy to design patient-specific treatment regimens. Taken together, the successful development of this DLM-GelMA sandwich structure on the chip could faithfully reflect the tumor microenvironment and immune response, accelerating the screening process of drug molecules and providing insights for practical medicine.
PubMed: 38953554
DOI: 10.1039/d4lc00278d -
Immunology Jul 2024The adverse effects observed in some cancer patients treated with erythropoiesis-stimulating agents such as erythropoietin (EPO) might be due to the latter's well-known...
The adverse effects observed in some cancer patients treated with erythropoiesis-stimulating agents such as erythropoietin (EPO) might be due to the latter's well-known immunosuppressive functions. Here, we used a mouse model of syngeneic triple-negative breast cancer to explore EPO's immunomodulatory role in a tumour setting. Our results showed that EPO treatment promotes tumour growth, exacerbates the 'immune desert', and results in a 'cold tumour'. EPO treatment changed the immune cell distribution in peripheral blood, secondary lymphoid organs, and the tumour microenvironment (TME). Our in-depth analysis showed that EPO mainly impacts CD4 T cells by accelerating their activation in the spleen and thus their subsequent exhaustion in the TME. This process is accompanied by a general elevation of CD39 expression by several immune cells (notably CD4 T cells in the tumour and spleen), which promotes an immunosuppressive TME. Lastly, we identified a highly immunosuppressive CD39 regulatory T cell population (ICOS, CTLA4, Ki67) as a potential biomarker of the risk of EPO-induced tumour progression. EPO displays pleiotropic immunosuppressive functions and enhances mammary tumour progression in mice.
PubMed: 38953295
DOI: 10.1111/imm.13832 -
PeerJ 2024This study explored the utilization of luffa sponge (LS) in enhancing acetification processes. LS is known for having high porosity and specific surface area, and can...
BACKGROUND
This study explored the utilization of luffa sponge (LS) in enhancing acetification processes. LS is known for having high porosity and specific surface area, and can provide a novel means of supporting the growth of acetic acid bacteria (AAB) to improve biomass yield and acetification rate, and thereby promote more efficient and sustainable vinegar production. Moreover, the promising potential of LS and luffa sponge coated with κ-carrageenan (LSK) means they may represent effective alternatives for the co-production of industrially valuable bioproducts, for example bacterial cellulose (BC) and acetic acid.
METHODS
LS and LSK were employed as adsorbents for UMCC 2951 in a submerged semi-continuous acetification process. Experiments were conducted under reciprocal shaking at 1 Hz and a temperature of 32 °C. The performance of the two systems (LS-AAB and LSK-AAB respectively) was evaluated based on cell dry weight (CDW), acetification rate, and BC biofilm formation.
RESULTS
The use of LS significantly increased the biomass yield during acetification, achieving a CDW of 3.34 mg/L versus the 0.91 mg/L obtained with planktonic cells. Coating LS with κ-carrageenan further enhanced yield, with a CDW of 4.45 mg/L. Acetification rates were also higher in the LSK-AAB system, reaching 3.33 ± 0.05 g/L d as opposed to 2.45 ± 0.05 g/L d for LS-AAB and 1.13 ± 0.05 g/L d for planktonic cells. Additionally, BC biofilm formation during the second operational cycle was more pronounced in the LSK-AAB system (37.0 ± 3.0 mg/L, as opposed to 25.0 ± 2.0 mg/L in LS-AAB).
CONCLUSIONS
This study demonstrates that LS significantly improves the efficiency of the acetification process, particularly when enhanced with κ-carrageenan. The increased biomass yield, accelerated acetification, and enhanced BC biofilm formation highlight the potential of the LS-AAB system, and especially the LSK-AAB variant, in sustainable and effective vinegar production. These systems offer a promising approach for small-scale, semi-continuous acetification processes that aligns with eco-friendly practices and caters to specialized market needs. Finally, this innovative method facilitates the dual production of acetic acid and bacterial cellulose, with potential applications in biotechnological fields.
Topics: Carrageenan; Acetobacter; Biomass; Acetic Acid; Luffa; Adsorption; Cellulose; Biofilms
PubMed: 38952965
DOI: 10.7717/peerj.17650 -
Biotechnology For Biofuels and... Jun 2024Research on protein production holds significant importance in the advancement of food technology, agriculture, pharmaceuticals, and bioenergy. Aspergillus niger stands...
BACKGROUND
Research on protein production holds significant importance in the advancement of food technology, agriculture, pharmaceuticals, and bioenergy. Aspergillus niger stands out as an ideal microbial cell factory for the production of food-grade proteins, owing to its robust protein secretion capacity and excellent safety profile. However, the extensive oxidative folding of proteins within the endoplasmic reticulum (ER) triggers ER stress, consequently leading to protein misfolding reactions. This stressful phenomenon results in the accelerated generation of reactive oxygen species (ROS), thereby inducing oxidative stress. The accumulation of ROS can adversely affect intracellular DNA, proteins, and lipids.
RESULT
In this study, we enhanced the detoxification of ROS in A. niger (SH-1) by integrating multiple modules, including the NADPH regeneration engineering module, the glutaredoxin system, the GSH synthesis engineering module, and the transcription factor module. We assessed the intracellular ROS levels, growth under stress conditions, protein production levels, and intracellular GSH content. Our findings revealed that the overexpression of Glr1 in the glutaredoxin system exhibited significant efficacy across various parameters. Specifically, it reduced the intracellular ROS levels in A. niger by 50%, boosted glucoamylase enzyme activity by 243%, and increased total protein secretion by 88%.
CONCLUSION
The results indicate that moderate modulation of intracellular redox conditions can enhance overall protein output. In conclusion, we present a strategy for augmenting protein production in A. niger and propose a potential approach for optimizing microbial protein production system.
PubMed: 38951910
DOI: 10.1186/s13068-024-02542-0 -
Journal of Nanobiotechnology Jul 2024Diabetic wounds present significant challenges, specifically in terms of bacterial infection and delayed healing. Therefore, it is crucial to address local bacterial...
BACKGROUND
Diabetic wounds present significant challenges, specifically in terms of bacterial infection and delayed healing. Therefore, it is crucial to address local bacterial issues and promote accelerated wound healing. In this investigation, we utilized electrospinning to fabricate microgel/nanofiber membranes encapsulating MXene-encapsulated microgels and chitosan/gelatin polymers.
RESULTS
The film dressing facilitates programmed photothermal therapy (PPT) and mild photothermal therapy (MPTT) under near-infrared (NIR), showcasing swift and extensive antibacterial and biofilm-disrupting capabilities. The PPT effect achieves prompt sterilization within 5 min at 52 °C and disperses mature biofilm within 10 min. Concurrently, by adjusting the NIR power to induce local mild heating (42 °C), the dressing stimulates fibroblast proliferation and migration, significantly enhancing vascularization. Moreover, in vivo experimentation successfully validates the film dressing, underscoring its immense potential in addressing the intricacies of diabetic wounds.
CONCLUSIONS
The MXene microgel-loaded nanofiber dressing employs temperature-coordinated photothermal therapy, effectively amalgamating the advantageous features of high-temperature sterilization and low-temperature promotion of wound healing. It exhibits rapid, broad-spectrum antibacterial and biofilm-disrupting capabilities, exceptional biocompatibility, and noteworthy effects on promoting cell proliferation and vascularization. These results affirm the efficacy of our nanofiber dressing, highlighting its significant potential in addressing the challenge of diabetic wounds struggling to heal due to infection.
Topics: Wound Healing; Nanofibers; Photothermal Therapy; Animals; Bandages; Anti-Bacterial Agents; Mice; Biofilms; Chitosan; Male; Diabetes Mellitus, Experimental; Temperature; Rats; Infrared Rays; Cell Proliferation; Rats, Sprague-Dawley; Humans; Wound Infection
PubMed: 38951903
DOI: 10.1186/s12951-024-02621-2 -
One Health Outlook Jul 2024One Health is being promoted as a transformative approach in health, conservation, and environmental sustainability. The polycrisis of climate change, pandemics, food...
One Health is being promoted as a transformative approach in health, conservation, and environmental sustainability. The polycrisis of climate change, pandemics, food insecurity, biodiversity loss, pollution and inequity is creating an urgency to evolve the epistemology and methods of One Health. However, the amount of effort placed into critical and systematic reflection on One Health is outweighed by advocacy for its use, or for expanding its scope of practice. This paper advocates for reflective One Health practice to foster new ways of knowing and doing that are helpful in the face of a rapidly narrowing window of opportunity to preserve the social and environmental factors that secure health and resilience for all species and generations. We propose six areas for reflection; (1) how to moderate conformity so that One Health does not become its own silo; (2) finding the moral purpose of One Health to align actions with desired outcomes; (3) coping with the problem of too many interacting problems; (4) the strategic trajectory of growth to accelerate action on root causes and ensure One Health is future-ready; (5) how to identify priorities across a vast array of problems, values, and needs and (6) how to know if we are making the world healthier and safer and for whom. Reflective practice requires investment in ongoing conversation to guard against over-confidence that we have captured the "one right way" to meet changing expectations and circumstances in a fair and effective way. Our intention is to stimulate thinking and discussion within the One Health community to ensure that "doing is shaped by knowing". We hope One Health will continue to be an emergent and highly variable set of ever more effective practices that constantly changes in response to the complex, interconnected and changing problems facing the health of people, animals, and the environment.
PubMed: 38951887
DOI: 10.1186/s42522-024-00106-8 -
BMC Plant Biology Jun 2024Drought poses significant risks to maize cultivation by impairing plant growth, water uptake and yield; nano priming offers a promising avenue to mitigate these effects...
Drought poses significant risks to maize cultivation by impairing plant growth, water uptake and yield; nano priming offers a promising avenue to mitigate these effects by enhancing plant water relations, stress tolerance and overall productivity. In the current experiment, we tested a hypothesis that seed priming with iron oxide nanoparticles (n-FeO) can improve maize performance under water stress by improving its growth, water relations, yield and biochemical attributes. The experiment was conducted on a one main plot bisected into two subplots corresponding to the water and drought environments. Within each subplot, maize plants were raised from n-FeO primed seeds corresponding to 0 mg. L (as control treatment), 25, 50, 75, and 100 mg. L (as trial treatments). Seed priming with n-FeO at a concentration of 75 mg. L improved the leaf relative water content, water potential, photosynthetic water use efficiency, and leaf intrinsic water use efficiency of maize plants by 13%, 44%, 64% and 17%, respectively compared to control under drought stress. The same treatments improved plant biochemical attributes such as total chlorophyll content, total flavonoids and ascorbic acid by 37%, 22%, and 36%, respectively. Seed priming with n-FeO accelerated the functioning of antioxidant enzymes such as SOD and POD and depressed the levels of leaf malondialdehyde and hydrogen peroxide significantly. Seed priming with n-FeO at a concentration of 75 mg. L improved cob length, number of kernel rows per cob, and 100 kernel weight by 59%, 27% and 33%, respectively, under drought stress. Seed priming with n-FeO can be used to increase maize production under limited water scenarios.
Topics: Zea mays; Seeds; Water; Dehydration; Droughts; Photosynthesis; Ferric Compounds; Chlorophyll; Plant Leaves
PubMed: 38951758
DOI: 10.1186/s12870-024-05324-w