Nanozyme-Based Microfluidic Chip System for pH-Regulated Pretreatment and Sensitive Sensing.

Nanozymes, possessing nanomaterial properties and catalytic activities, offer great opportunities to design sensitive analytical detection systems. However, the low interference resistance of nanozymes poses a significant limitation on the precise detection of target substances. Herein, a nanozyme-based microfluidic chip system for pH-regulated pretreatment and sensitive sensing of cysteine (Cys) is reported. The copper metal-organic framework (Cu MOF) exhibits good cysteine oxidase-like activity at pH 7.0, while demonstrating excellent laccase-like activity at pH 8.0. Taking advantage of the pH-regulated enzyme-like activity, the integrated microfluidic device involving the immobilization of Cu MOF eliminates the interference of dopamine (DA) and accurately detects the target Cys. Compared with the untreated reaction system, the developed nanozyme system shows a significantly improved accuracy in detecting Cys, with an R2 value of 0.9914. This work provides an efficient method to enhance the interference resistance of nanozymes and broadens the application in sample pretreatment.

Analysis of a case report of meningitis caused by Listeria monocytogenes.

Background: Listeria monocytogenes is a Gram-positive bacterium transmitted to humans through contaminated food, water, and animal faeces, posing a public health risk. Listeria monocytogenes is difficult to isolate and is not sensitive to first-line treatment with broad-spectrum cephalosporins for bacterial meningitis. Listeria meningitis is rare but can progress rapidly and may be accompanied by serious complications (hydrocephalus, ventricular inflammation, cerebral palsy, and brain abscess) and a high mortality rate. Case presentation: It is a retrospective analysis of the clinical characteristics and treatment of a rare case of Listeria monocytogenes infection. Using laboratory indicators such as white blood cells (WBC), C-reactive protein (CRP), and procalcitonin (PCT), three detection methods (cerebrospinal fluid/blood culture), Targeted gene sequencing technology (tNGS), and Metagenomic next-generation sequencing technology (mNGS) combined with clinical manifestations of patients, analyze the use plan and prognosis of antibiotics in patients. The patient in this case initially had neurological symptoms such as fever, headache, unclear consciousness, and vomiting; laboratory indicators include elevated WBC, CRP, and PCT. Listeria monocytogenes was cultured in both the patient's cerebrospinal fluid and blood samples. After treatment with penicillin and meropenem, the patient recovered and was discharged without any sequelae. Conclusion: Due to the rarity of Listeria monocytogenes, there may be deficiencies and difficulties in clinical differential diagnosis, making it difficult to achieve targeted antibiotic treatment. Therefore, accurate identification of Listeria monocytogenes and relevant laboratory inflammation indicator testing, combined with traditional culture methods and NGS testing, through empirical coverage of Listeria monocytogenes, targeted antibiotic treatment ultimately impacts clinical outcomes significantly.

Post-traumatic Reactions and Social-Emotional Competence Among Chinese High School Students Experiencing COVID-19 Lockdown: A Network Analysis.

In the post-pandemic era, psychological traumas have emerged as major mental health issues. However, the post-traumatic reactions and their connections with social-emotional competence among high school students experiencing COVID-19 lockdown have not been adequately explored. This study aimed to reveal the characteristics of their positive and negative post-traumatic reactions, and their connections with social-emotional competence. Network analysis was used on data from 1096 Chinese high school students who experienced COVID-19 lockdown. Measures included the DSECS-S, the PTGI and the PC-PTSD-5. The results revealed that "Valuing life" and "Recalling unwillingly" were identified as core factors of post-traumatic reactions, while "Having close friendships", "Getting along well with others" and "Respecting others' emotions" played a bridging role in connecting the communities of social-emotional competence and post-traumatic reactions. This study enriches research on post-traumatic reactions, emphasizing the importance of implementing social-emotional competence programs to tackle mental health crises.

Performance of Machine Learning Algorithms in Predicting Prolonged Mechanical Ventilation in Patients with Blunt Chest Trauma.

Purpose: Mechanical ventilation (MV) is one of the most common treatments for patients with blunt chest trauma (BCT) admitted to the intensive care unit (ICU). Our study aimed to investigate the performance of machine learning algorithms in predicting the prolonged duration of mechanical ventilation (PDMV) in patients with BCT. Methods: In this single-center observational study, patients with BCT who were treated with MV through nasal or oral intubation were selected. PDMV was defined as the duration of mechanical ventilation ≥7 days after endotracheal intubation (normal vs prolonged MV; dichotomous outcomes). K-means was used to cluster data from the original cohort by an unsupervised learning method. Multiple machine learning algorithms were used to predict DMV categories. The most significant predictors were identified by feature importance analysis. Finally, a decision tree based on the chi-square automatic interaction detection (CHAID) algorithm was developed to study the cutoff points of predictors in clinical decision-making. Results: A total of 426 patients and 35 characteristics were included. K-means clustering divided the cohort into two clusters (high risk and low risk). The area under the curve (AUC) of the DMV classification algorithms ranged from 0.753 to 0.923. The importance analysis showed that the volume of pulmonary contusion (VPC) was the most important feature to predict DMV. The prediction accuracy of the decision tree based on CHAID reached 86.4%. Conclusion: Machine learning algorithms can predict PDMV in patients with BCT. Therefore, limited medical resources can be more appropriately allocated to BCT patients at risk for PDMV.

Paths of cognitive and social-emotional delays before age three in rural China: Predictive power on skills at preschool age.

Cognitive and social-emotional development in the first three years of life is associated with later skills. However, little is known about the paths of developmental delays in both cognitive and social-emotional skills before age 3 or to what extent these paths predict later developmental outcomes. The aim of this study is to examine the associations between the different paths of developmental delays in both cognitive and social-emotional skills of children before age 3 and the levels of development of the children when they are preschool age. Using a longitudinal data collected at three time points from 1245 children and their caregivers in rural China, we identified four different paths of developmental delays in cognitive and social-emotional before age 3 and examined how these paths are associated with different levels of developmental outcomes at preschool age. We used a non-parametric standardization approach and an ordinary least squares model to perform our analyses. Findings show that rates of developmental delays in either cognitive or social-emotional domain or both domains are high at all different time points, ranging from 20% to 55% for cognitive delays and 42% to 61% for social-emotional delays. Over half of children experienced deteriorating levels of either cognitive or social-emotional development before age 3. A large share of children was found to be persistently delayed in either domain. Only a small share of children raised their levels of development in either domain before age 3. In addition, we identified certain socioeconomic status of the family that are associated with never or deteriorating path of child developmental delays. More importantly, we revealed that different paths of developmental delays before age 3 have predictive power on different levels of developmental outcomes at preschool age. Our results suggest that actions are needed at the earliest times to improve child development when children are still infants or toddlers.

Maternal Gestational Diabetes Mellitus and High-Fat Diet Influenced Hepatic Polyunsaturated Fatty Acids Profile in the Offspring of C57BL/6J Mice.

SCOPE: This research examines the effects of maternal high-fat (HF) diet and gestational diabetes mellitus (GDM) on offspring lipid metabolism and polyunsaturated fatty acids (PUFA) profile. METHODS AND RESULTS: GDM is induced using the insulin receptor antagonist S961. Weaning offspring are categorized into HF-GDM, HF-CON, NC-GDM, and NC-CON groups based on maternal diet or GDM. Adult offspring are then grouped into NC-CON-NC, NC-CON-HF, NC-GDM-NC, NC-GDM-HF, HF-CON-NC, HF-CON-HF, HF-GDM-NC, and HF-GDM-HF according to dietary patterns. Gas chromatography determines PUFA composition. Western blot assesses PI3K/Akt signaling pathway-related protein expression. Feeding a normal chow diet until adulthood improves the distribution of hepatic PUFA during weaning across the four groups. PI3K expression is upregulated during weaning in HF-CON and HF-GDM, particularly in HF-CON-NC and HF-GDM-NC, compared to NC-CON-NC during adulthood. Akt expression increases in NC-GDM-NC after weaning with a normal diet. The hepatic PUFA profile in HF-CON-HF significantly distinguishes among the maternal generation health groups. Maternal HF diet exacerbates the combined impact of maternal GDM and offspring HF diet on hepatic PUFA and PI3K/Akt signaling pathway-related proteins during adulthood. CONCLUSIONS: Early exposure to HF diets and GDM affects hepatic PUFA profiles and PI3K/Akt signaling pathway protein expression in male offspring during weaning and adulthood.

In Situ Defect Engineering of Fe-MIL for Self-Enhanced Peroxidase-Like Activity.

Defect engineering is an effective strategy to enhance the enzyme-like activity of nanozymes. However, previous efforts have primarily focused on introducing defects via de novo synthesis and post-synthetic treatment, overlooking the dynamic evolution of defects during the catalytic process involving highly reactive oxygen species. Herein, a defect-engineered metal-organic framework (MOF) nanozyme with mixed linkers is reported. Over twofold peroxidase (POD)-like activity enhancement compared with unmodified nanozyme highlights the critical role of in situ defect formation in enhancing the catalytic performance of nanozyme. Experimental results reveal that highly active hydroxyl radical (•OH) generated in the catalytic process etches the 2,5-dihydroxyterephthalic acid ligands, contributing to electronic structure modulation of metal sites and enlarged pore sizes in the framework. The self-enhanced POD-like activity induced by in situ defect engineering promotes the generation of •OH, holding promise in colorimetric sensing for detecting dichlorvos. Utilizing smartphone photography for RGB value extraction, the resultant sensing platform achieves the detection for dichlorvos ranging from 5 to 300 ng mL-1 with a low detection limit of 2.06 ng mL-1. This pioneering work in creating in situ defects in MOFs to improve catalytic activity offers a novel perspective on traditional defect engineering.

Mechanism of Mitochondrial Kinetic Imbalance and Nrf2 Signaling Pathway-Mediated Oxidative Stress in Nickel and/or Chromium-Induced Kidney Injury in Mice.

Nickel and chromium are both common heavy metals that pose serious environmental and health hazards. However, the exact mechanism by which nickel and/or chromium cause renal injury is unclear. Therefore, we explored the molecular mechanisms of renal injury caused by nickel and/or chromium poisoning from the perspective of mitochondrial dynamics and the Nrf2 antioxidant pathway. In this study, eighty 6-week-old C57BL/6J mice were randomly divided into four groups: control (Con, untreated), nickel (Ni, 110 mg/L Ni2+), chromium (Cr, 50 mg/L Cr6+), and combined nickel-chromium (Ni + Cr, 110 mg/L Ni2+, 50 mg/L Cr6+). The results showed that chronic nickel and/or chromium exposure inhibited body weight gain and impaired kidney function and structure in mice. Chronic nickel and/or chromium exposure led to the disruption of mitochondrial dynamics and thus induced oxidative stress. On the other hand, the Nrf2 antioxidant pathway may play an important regulatory role in mitigating oxidative stress-induced oxidative damage in kidney. The present study partially elucidated the molecular mechanism of renal injury induced by nickel and/or chromium exposure in mice and the regulatory role of the Nrf2 pathway in inducing oxidative injury from the perspective of mitochondrial dynamics. This provides a theoretical basis for the development of prevention and control strategies, and environmental protection measures.

Effective microorganism combinations improve the quality of compost-bedded pack products in heifer barns: exploring pack bacteria-fungi interaction mechanisms.

BACKGROUND: Compost-bedded pack barns (CBP) are getting huge attention as an alternative housing system for dairy cows due to their beneficial impact on animal welfare. Effective microorganisms (EM) inoculums are believed to enhance compost quality, improve soil structure and benefit the environment. However, little information is available on the impact of incubation with external EM combinations on the barn environment, compost quality and microbial diversity in CBP. This experiment was carried out to investigate the effect of inoculating different combinations of EM [Lactobacillus plantarum (L), Compound Bacillus (B) and Saccharomyces cerevisiae (S)] on compost quality and microbial communities of CBP products, as well as the relationship with the heifers' barn environment. CBP barns were subjected to the following four treatments: CON with no EM inoculum, LB/LS/LBS were Incubated with weight ratios of 1:2 (L: B), 1:2 (L: S), 1:1:1 (L: B: S), respectively. RESULTS: The EM inoculation (LB, LS, LBS) reduced the concentration of respirable particulate matter (PM10 and PM2.5) in the CBP, and decreased the serum total protein and total cholesterol levels in heifers. Notably, LBS achieved the highest content of high-density lipoprotein compared to other treatments. Microbiome results revealed that EM inoculation reduced the bacterial abundance (Chao1 index) and fungal diversity (Shannon & Simpson indexes), while increasing the relative abundance of various bacterial genera (Pseudomonas, Paracoccus, Aequorivita) and fungi (Pestalotiopsis), which are associated with cellulose decomposition that ultimately resulted in accelerating organic matter degradation and humification. Furthermore, high nutrient elements (TK&TP) and low mycotoxin content were obtained with EM inoculation, with LBS showing a particularly pronounced effect. Meanwhile, LBS contributed to a decline in the proportion of fungal pathogen categories but also led to an increase in fungal saprotroph categories. CONCLUSION: Generally, EM inoculation positively impacted compost product quality as organic fertilizer and barn environment by modifying the abundance of cellulolytic bacteria and fungi, while inhibiting the reproduction of pathogenic microbes, especially co-supplementing with L, B and S achieved an amplifying effect.

Chromosome-level genome provides new insight into the overwintering process of Korla pear (Pyrus sinkiangensis Yu).

Korla pear has a unique taste and aroma and is a breeding parent of numerous pear varieties. It is susceptible to Valsa mali var. pyri, which invades bark wounded by freezing injury. Its genetic relationships have not been fully defined and could offer insight into the mechanism for freezing tolerance and disease resistance. We generated a high-quality, chromosome-level genome assembly for Korla pear via the Illumina and PacBio circular consensus sequencing (CCS) platforms and high-throughput chromosome conformation capture (Hi-C). The Korla pear genome is ~ 496.63 Mb, and 99.18% of it is assembled to 17 chromosomes. Collinearity and phylogenetic analyses indicated that Korla might be derived from Pyrus pyrifolia and that it diverged ~ 3.9-4.6 Mya. During domestication, seven late embryogenesis abundant (LEA), two dehydrin (DHN), and 54 disease resistance genes were lost from Korla pear compared with P. betulifolia. Moreover, 21 LEA and 31 disease resistance genes were common to the Korla pear and P. betulifolia genomes but were upregulated under overwintering only in P. betulifolia because key cis elements were missing in Korla pear. Gene deletion and downregulation during domestication reduced freezing tolerance and disease resistance in Korla pear. These results could facilitate the breeding of novel pear varieties with high biotic and abiotic stress resistance.

Minocycline alleviates microglia ferroptosis by inhibiting HO-1 during cerebral ischemia-reperfusion injury.

OBJECTIVE: Ischemic stroke is a leading cause of death and disability in individuals worldwide. Cerebral ischemia-reperfusion injury (CIRI) typically results in severe secondary injury and complications following reperfusion therapy. Microglia play critical roles in the inflammatory reaction of CIRI. However, less attention has been given to microglial death in this process. Our study aims to explore microglial death in CIRI and the effects and mechanism of minocycline treatment on microglia. METHODS: A middle cerebral artery occlusion (MCAO) model was applied to induce CIRI in rats. At 0 h, 24 h and 48 h post-operation, rats were intraperitoneally injected with 45 mg/kg minocycline. Neurological deficit scoring, 2,3,5-triphenyltetrazolium chloride (TTC) staining, assessment of activated microglia and examination of mitochondrial structure were conducted and checked at 72 h after reperfusion. Additionally, an in vitro model of oxygen-glucose deprivation/reperfusion (OGD/R) model was established. BV-2 cells were treated with various pharmacological inhibitors of cell death or minocycline. Cell viability, lipid peroxidation, mitochondrial structure and function, and labile Fe2+ and ferroptosis-associated gene/protein levels were measured. Hemin was used for further validation after transcriptome analysis. RESULTS: In the MCAO and OGD/R models, ferroptosis was identified as a major form of microglial death. Minocycline inhibited microglia ferroptosis by reducing HO-1 expression. In addition, minocycline improved mitochondrial membrane potential, mitochondrial structures and microglial survival in vivo. Minocycline also decreased labile Fe2+ levels, lipid peroxidation, and expression of ferritin heavy chain (FTH) and it improved mitochondrial structure and function in vitro. Upregulation of HO-1 counteracted the protective effect of minocycline. CONCLUSION: Ferroptosis is a major form of microglial death in CIRI. The protective mechanism of minocycline in CIRI partially hinges on its ability to effectively ameliorate microglia ferroptosis by downregulating HO-1 expression. Consequently, targeting microglia ferroptosis is a promising treatment for CIRI.

Expression of insulin-like growth factor binding protein 5 in the vaginal wall tissues of older women with pelvic organ prolapse.

This study aimed to investigate the expression and significance of insulin-like growth factor binding protein 5 (IGFBP5) and extracellular matrix (ECM) related proteins in anterior vaginal wall tissues among aged pelvic organ prolapse (POP) patients. Tissues from the anterior vaginal wall were collected from 28 patients with POP and 20 patients without POP. The expression of protein and mRNA levels of IGFBP5 and ECM related proteins were evaluated in the vaginal wall tissues using immunohistochemistry, western blotting, and RT-qPCR techniques. The expression levels were then compared with clinical parameters. The expression levels of protein and mRNA of IGFBP5, collagen I, and collagen III were significantly lower in the POP group. Protein and mRNA expression levels of MMP2 were significantly higher in the POP group. IGFBP5 protein and mRNA expression levels were negatively correlated with age and significantly lower in older POP patients (≥ 65 years old) compared to younger POP patients (< 65 years old). IGFBP5 protein and mRNA expression levels were also significantly lower in POP-Q stage IV patients compared to POP-Q stage III patients. IGFBP5 expression level is negatively correlated with the age and severity of prolapse. The significant decrease in IGFBP5 expression may play a crucial part in the aging process and the occurrence of POP.

Synergistically improve the strength and porosity of carbon paper by using a novel phenol formaldehyde resin modified with cellulose nanofiber for proton exchange membrane fuel cells.

To optimize the imbalance between the interfacial bonding and porosity properties of carbon paper (CP) caused by phenol formaldehyde resin (PF) impregnation, and therefore improve the performance of proton exchange membrane fuel cells (PEMFCs), a new approach through cellulose nanofibers grafted with methyl methacrylate (CNFM) as a modified reinforcement and pore-forming agent for PF is investigated. Through suppressing the methylene backbone fracture of CNFM-modified PF during its thermal depolymerization, the interfacial bonding between PF matrix carbon and carbon fibers is enhanced. Compared with unmodified CP, the in-plane resistivity of CNFM-modified CP is reduced by 35.78 %, while the connected porosity increases to 82.26 %, and more homogeneous pore size distribution (PSD) in the range of 20-40 µm is obtained for CNFM-modified CP. Besides, the tensile strength, flexural strength, and air permeability of CNFM-modified CP increase by 72.78 %, 298.4 %, and 103.97 %, respectively. In addition, CNFM-modified CP achieves the peak power density of PEMFCs to 701.81 mW·cm-2, exhibiting 10.98 % improvement compared with commercial CP (632.39 mW·cm-2), evidently achieving an integral promotion of CP and comprehensive performance.

Nasal Drug Delivery and Nose-to-Brain Delivery Technology Development Status and Trend Analysis: Based on Questionnaire Survey and Patent Analysis.

Nasal administration is a non-invasive method of drug delivery that offers several advantages, including rapid onset of action, ease of use, no first-pass effect, and fewer side effects. On this basis, nose-to-brain delivery technology offers a new method for drug delivery to the brain and central nervous system, which has attracted widespread attention. In this paper, the development status and trends of nasal drug delivery and nose-to-brain delivery technology are deeply analyzed through multiple dimensions: literature research, questionnaire surveys, and patent analysis. First, FDA-approved nasal formulations for nose-to-brain delivery were combed. Second, we collected a large amount of relevant information about nasal drug delivery through a questionnaire survey of 165 pharmaceutical industry practitioners in 28 provinces and 161 different organizations in China. Third, and most importantly, we conducted a patent analysis of approximately 700+ patents related to nose-to-brain delivery, both domestically and internationally. This analysis was conducted in terms of patent application trends, technology life cycle, technology composition, and technology evolution. The LDA topic model was employed to identify technological topics in each time window (1990-2023), and the five key major evolution paths were extracted. The research results in this paper will provide useful references for relevant researchers and enterprises in the pharmaceutical industry, promoting the further development and application of nasal drug delivery and nose-to-brain delivery technology.

Application progress of exergames in health interventions for the elderly. / 运动游戏在老年人健康干预中的应用进展.

With the aging population in China, health issues among the elderly are becoming increasingly prominent, leading to a rapidly growing demand for health interventions for the elderly. Exergames are one of the important emerging methods in the field of health interventions for the elderly, widely used and yielding positive results. While research on exergames is well-established abroad, it is still in its infancy in China, lacking reports on the types, interaction forms, intervention content, application status, and effectiveness of exergames. Exergames are suitable for widespread use among the elderly in China, and there is a need to accelerate the development and application of exergames in the field of health interventions for the elderly in China.

Examining the impact of flipped learning on second language development: A quasi-experiment in higher education.

This article reports on a study that examined the impact of a flipped English as a Foreign Language (EFL) course on college students' second language (L2) development. Specifically, an 18-week quasi-experiment was administered in a general English course at a Chinese university, with a total of 612 first-year students randomly assigned to the treatment (n = 137) and control (n = 475) groups. Using the propensity score matching and difference-in-differences (PSM-DID) model, we analyzed norm scores on high-stakes assessments administered on the entry and completion of the intervention. The results revealed a causal link between flipped learning (FL) and improved L2 language performance though the impact of FL had substantial heterogeneity as greater gains were found in reading than in writing and listening. Quantile regression analysis suggested the effectiveness of FL varied greatly by proficiency level in that students in the lowest quantiles achieved high improvement in reading and listening but moderate improvement in writing. We discuss the pedagogical implications of these findings to college L2 flipped instruction and recommend that future research be conducted in a more rigorous experimental design to obtain robust and accurate estimates of the effectiveness of FL.

Glycyrrhetinic acid triggers a protective autophagy by inhibiting the JAK2/STAT3 pathway in cerebral ischemia/reperfusion injury.

Cerebral ischemia/reperfusion injury (CIRI) is a common feature of ischemic stroke leading to a poor prognosis. Effective treatments targeting I/R injury are still insufficient. The study aimed to investigate the mechanisms, by which glycyrrhizic acid (18ß-GA) in ameliorates CIRI. Our results showed that 18ß-GA significantly decreased the infarct volume, neurological deficit scores, and pathological changes in the brain tissue of rats after middle cerebral artery occlusion. Western blotting showed that 18ß-GA inhibited the expression levels of phosphorylated JAK2 and phosphorylated STAT3. Meanwhile, 18ß-GA increased LC3-II protein levels in a reperfusion duration-dependent manner, which was accompanied by an increase in the Bcl-2/Bax ratio. Inhibition of 18ß-GA-induced autophagy by 3-methyladenine (3-MA) enhanced apoptotic cell death. In addition, 18ß-GA inhibited the JAK2/STAT3 pathway, which was largely activated in response to oxygen-glucose deprivation/reoxygenation. However, the JAK2/STAT3 activator colivelin TFA abolished the inhibitory effect of 18ß-GA, suppressed autophagy, and significantly decreased the Bcl-2/Bax ratio. Taken together, these findings suggested that 18ß-GA pretreatment ameliorated CIRI partly by triggering a protective autophagy via the JAK2/STAT3 pathway. Therefore might be a potential drug candidate for treating ischemic stroke.

Microplastics in soil affect the growth and physiological characteristics of Chinese fir and Phoebe bournei seedlings.

Pot experiments were conducted using Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) and Phoebe bournei (Hemsl.) Yang) to investigate whether soil microplastics adversely affect the nurturing and renewal of plantations. Microplastics composed of polyethylene and polypropylene with a size of 48 µm were used. The treatments included a control group (without microplastics) and groups treated with microplastic concentrations of 1% and 2% (w/w). The effects of microplastics on the growth, photosynthetic pigments in leaves, antioxidant systems, and osmotic regulation substances of the seedlings were analysed by measuring the seedling height, ground-line diameter growth, chlorophyll (chlorophyll a, chlorophyll b, and total chlorophyll) contents, antioxidant enzyme (superoxide dismutase, peroxidase, catalase) activities, and malondialdehyde, soluble sugar, and soluble protein levels. The results indicated that treatment with 1% polyethylene microplastics increased the chlorophyll a, total chlorophyll, and soluble protein contents in the leaves of both types of seedlings while inhibiting superoxide dismutase and peroxidase activities in P. bournei seedlings. Treatment with 2% polyethylene or polypropylene microplastics suppressed the chlorophyll a, chlorophyll b, and total chlorophyll contents; superoxide dismutase, peroxidase, and catalase activities; and soluble sugar and soluble protein levels in the leaves of both types of seedlings, resulting in reduced growth in terms of height and ground-line diameter. The physiological effects of polyethylene microplastics were more evident than those of polypropylene at the same concentration. The results demonstrated that microplastics can affect photosynthesis, the antioxidant system, and osmotic regulation in Chinese fir and P. bournei seedlings, thereby inhibiting their normal growth and development. Exposure to 1% (w/w) microplastics triggered stress responses in seedlings, whereas 2% (w/w) microplastics impeded seedling growth.